config: the resolution callbacks into the record go to zero (#36972)

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

python/sglang/srt/arg_groups/attention_hook.py

@@ -29,8 +29,14 @@ logger = logging.getLogger(__name__)
 
 
 def handle_attention_backend_compatibility(server_args: Any):
+    from sglang.srt.arg_groups.overrides import (
+        attention_backends_of,
+        model_config_of,
+        use_mla_backend,
+    )
+
     cfg = resolving_view(server_args)
-    model_config = server_args.get_model_config()
+    model_config = model_config_of(server_args)
 
     # The attention_backend write clusters of this handler moved to the
     # resolution pipeline (arg_groups/overrides.py), each invoked below at
@@ -127,7 +133,7 @@ def handle_attention_backend_compatibility(server_args: Any):
 
     run_post_process_pass(server_args, _cutedsl_prefill_backend_fill)
 
-    prefill_backend, decode_backend = server_args._resolved_attention_backends()
+    prefill_backend, decode_backend = attention_backends_of(resolved_view(server_args))
     if "trtllm_mha" in (prefill_backend, decode_backend):
         if prefill_backend == "trtllm_mha" and not (
             is_sm90_supported() or is_sm100_supported() or is_sm120_supported()
@@ -184,8 +190,8 @@ def handle_attention_backend_compatibility(server_args: Any):
     # Other platforms backends
     run_post_process_pass(server_args, _attention_backend_platform_fallbacks)
 
-    prefill_backend, decode_backend = server_args._resolved_attention_backends()
-    if server_args.use_mla_backend() and prefill_backend == "intel_xpu":
+    prefill_backend, decode_backend = attention_backends_of(resolved_view(server_args))
+    if use_mla_backend(server_args) and prefill_backend == "intel_xpu":
         raise ValueError(
             "intel_xpu backend is only supported on decode for MLA models, please set --decode-attention-backend to intel_xpu and do not set --attention-backend or --prefill-attention-backend to intel_xpu for prefill instead use triton."
         )
@@ -451,6 +457,8 @@ def handle_multi_item_scoring(server_args: Any):
     changing it silently could surprise users who intentionally picked
     a non-flashinfer backend.
     """
+    from sglang.srt.arg_groups.overrides import attention_backends_of
+
     cfg = resolving_view(server_args)
     if not cfg.enable_mis:
         return
@@ -488,7 +496,7 @@ def handle_multi_item_scoring(server_args: Any):
             chunked_prefill_size=-1,
         )
 
-    prefill_backend, decode_backend = server_args._resolved_attention_backends()
+    prefill_backend, decode_backend = attention_backends_of(resolved_view(server_args))
     assert prefill_backend == "flashinfer" and decode_backend == "flashinfer", (
         "Multi-item scoring requires flashinfer attention backend for custom attention mask support. "
         f"Please set --attention-backend flashinfer when using --enable-mis. "
@@ -497,6 +505,7 @@ def handle_multi_item_scoring(server_args: Any):
 
 
 def handle_deterministic_inference(server_args: Any):
+    from sglang.srt.arg_groups.overrides import model_config_of
     from sglang.srt.server_args import (
         RADIX_SUPPORTED_DETERMINISTIC_ATTENTION_BACKEND,
     )
@@ -549,7 +558,7 @@ def handle_deterministic_inference(server_args: Any):
         is_deepseek_model = False
         if parse_connector_type(cfg.model_path) != ConnectorType.INSTANCE:
             try:
-                hf_config = server_args.get_model_config().hf_config
+                hf_config = model_config_of(server_args).hf_config
                 model_arch = hf_config.architectures[0]
                 is_deepseek_model = model_arch in [
                     "DeepseekV2ForCausalLM",

python/sglang/srt/arg_groups/cuda_graph_hook.py

@@ -110,6 +110,8 @@ def apply_cuda_graph_compatibility(server_args: Any):
     prefill backend (this folds in the old
     --enforce-piecewise-cuda-graph contract).
     """
+    from sglang.srt.arg_groups.overrides import attention_backends_of, model_config_of
+
     cfg = resolving_view(server_args)
     if (Phase.PREFILL, "backend") in server_args._cuda_graph_config_locked:
         return
@@ -120,11 +122,13 @@ def apply_cuda_graph_compatibility(server_args: Any):
     # this runs first, so piecewise would otherwise silently win.
     if (
         cfg.cuda_graph_config.prefill.backend == Backend.BREAKABLE
-        and server_args.get_model_config().is_multimodal_piecewise_cuda_graph_supported
-        and not server_args.get_model_config().is_multimodal_breakable_cuda_graph_supported
+        and model_config_of(server_args).is_multimodal_piecewise_cuda_graph_supported
+        and not model_config_of(
+            server_args
+        ).is_multimodal_breakable_cuda_graph_supported
         # Keep trtllm_mla on the preferred breakable path, which now serves
         # MLA by falling back to the flashinfer MLA impl for extend.
-        and server_args._resolved_attention_backends()[0] != "trtllm_mla"
+        and attention_backends_of(resolved_view(server_args))[0] != "trtllm_mla"
     ):
         logger.info(
             "Using tc_piecewise CUDA graph for validated multimodal " "decoder prefill."
@@ -149,12 +153,14 @@ def disable_tc_piecewise_cudagraph_if_incompatible(server_args: Any):
     """TcPiecewise (torch.compile + piecewise) is incompatible with
     these configurations. Most are torch.compile / dynamo limitations.
     """
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
 
     rules = [
         (
             "model-arch blacklist",
-            lambda: server_args.get_model_config().is_piecewise_cuda_graph_disabled_model,
+            lambda: model_config_of(server_args).is_piecewise_cuda_graph_disabled_model,
         ),
         ("DP attention", lambda: resolved_view(server_args).enable_dp_attention),
         ("full torch.compile mode", lambda: cfg.enable_torch_compile),
@@ -177,8 +183,10 @@ def disable_tc_piecewise_cudagraph_if_incompatible(server_args: Any):
         ("LoRA", lambda: bool(cfg.lora_paths) or cfg.enable_lora),
         (
             "multimodal model",
-            lambda: server_args.get_model_config().is_multimodal
-            and not server_args.get_model_config().is_multimodal_piecewise_cuda_graph_supported,
+            lambda: model_config_of(server_args).is_multimodal
+            and not model_config_of(
+                server_args
+            ).is_multimodal_piecewise_cuda_graph_supported,
         ),
         (
             "GGUF quantization",
@@ -236,6 +244,8 @@ def disable_breakable_cudagraph_if_incompatible(server_args: Any):
     memory-saver rejection in its own __init__; config-time rules can be
     added here as they're discovered.
     """
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     from sglang.srt.configs.model_config import is_deepseek_v4
     from sglang.srt.layers.cp.bcg import supports_prefill_cp_bcg
@@ -245,7 +255,7 @@ def disable_breakable_cudagraph_if_incompatible(server_args: Any):
         # c4 indexer scratch is pinned in the capture pool and OOMs. Disable.
         (
             "DeepSeek-V4 (heavy capture-pool memory pressure)",
-            lambda: is_deepseek_v4(server_args.get_model_config().hf_config),
+            lambda: is_deepseek_v4(model_config_of(server_args).hf_config),
         ),
         # CP all_gather replay size mismatch under BCG.
         (
@@ -271,8 +281,10 @@ def disable_breakable_cudagraph_if_incompatible(server_args: Any):
         # Multimodal prefill replay faults under BCG; allowlisted archs opt back in.
         (
             "multimodal model",
-            lambda: server_args.get_model_config().is_multimodal
-            and not server_args.get_model_config().is_multimodal_breakable_cuda_graph_supported,
+            lambda: model_config_of(server_args).is_multimodal
+            and not model_config_of(
+                server_args
+            ).is_multimodal_breakable_cuda_graph_supported,
         ),
     ]
     for name, predicate in rules:
@@ -319,6 +331,8 @@ def disable_prefill_cuda_graph_for_deepseek_trtllm_mla(server_args: Any):
     breakable) trtllm_mla falls back to FlashAttention for prefill and regresses
     performance, so disable whichever prefill graph backend is in effect.
     """
+    from sglang.srt.arg_groups.overrides import attention_backends_of, model_config_of
+
     cfg = resolving_view(server_args)
 
     if (Phase.PREFILL, "backend") in server_args._cuda_graph_config_locked:
@@ -327,10 +341,10 @@ def disable_prefill_cuda_graph_for_deepseek_trtllm_mla(server_args: Any):
         return
     if (
         "DeepseekV3ForCausalLM"
-        not in server_args.get_model_config().hf_config.architectures
+        not in model_config_of(server_args).hf_config.architectures
     ):
         return
-    prefill_attention_backend, _ = server_args._resolved_attention_backends()
+    prefill_attention_backend, _ = attention_backends_of(resolved_view(server_args))
     if prefill_attention_backend != "trtllm_mla":
         return
     logger.warning(
@@ -362,7 +376,7 @@ def apply_deepep_adjustments(server_args: Any):
         if bs is None:
             # 2048 = documented prefill default; max_bs unresolved here.
             max_bs = cfg.cuda_graph_config.prefill.max_bs or 2048
-            bs = server_args._generate_prefill_cuda_graph_batch_sizes(max_bs)
+            bs = generate_prefill_cuda_graph_batch_sizes(server_args, max_bs)
         aligned = sorted({((b + 7) // 8) * 8 for b in bs})
         if aligned != sorted(bs):
             logger.info(
@@ -389,6 +403,8 @@ def apply_inkling_prefill_cuda_graph_default(server_args: Any):
     auto-disabled for this multimodal arch, and declarative model overrides
     materialize too late to steer cuda-graph resolution. Honors an explicit
     --cuda-graph-backend-prefill / --disable-prefill-cuda-graph."""
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if (
         cfg.cuda_graph_backend_prefill is not None
@@ -396,7 +412,7 @@ def apply_inkling_prefill_cuda_graph_default(server_args: Any):
         or parse_connector_type(cfg.model_path) == ConnectorType.INSTANCE
     ):
         return
-    arch = server_args.get_model_config().hf_config.architectures[0]
+    arch = model_config_of(server_args).hf_config.architectures[0]
     if arch in (
         "InklingForConditionalGeneration",
         "InklingForConditionalGenerationMTP",
@@ -409,13 +425,15 @@ def apply_inkling_prefill_cuda_graph_default(server_args: Any):
 
 
 def apply_muse_glimmer_prefill_cuda_graph_max_bs_default(server_args: Any):
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if (
         cfg.cuda_graph_max_bs_prefill is not None
         or parse_connector_type(cfg.model_path) == ConnectorType.INSTANCE
     ):
         return
-    arch = server_args.get_model_config().hf_config.architectures[0]
+    arch = model_config_of(server_args).hf_config.architectures[0]
     if arch in ("MuseGlimmerForCausalLM", "MuseGlimmerForConditionalGeneration"):
         declare_resolution(
             server_args,
@@ -430,7 +448,7 @@ def handle_cuda_graph_config(server_args: Any):
     parse_cuda_graph_config(server_args)
     apply_cuda_graph_compatibility(server_args)
     apply_deepep_adjustments(server_args)
-    server_args._apply_cuda_graph_disaggregation_roles()
+    apply_cuda_graph_disaggregation_roles(server_args)
     validate_cuda_graph_config(server_args)
     # Warn on the final resolved config (not inside the compat cascade —
     # that path is skipped when the user explicitly sets the backend,
@@ -453,3 +471,102 @@ def validate_cuda_graph_config(server_args: Any):
                 f"--cuda-graph-config[{phase}].backend={backend!r} not allowed; "
                 f"allowed: {ALLOWED_BACKENDS_PER_PHASE[phase]}"
             )
+
+
+def generate_prefill_cuda_graph_batch_sizes(server_args: Any, max_bs: int):
+    """
+    Generate the list of batch sizes for prefill CUDA graph capture
+    based on max_bs. For tc_piecewise prefill, bs carries the
+    captured token count (one shape knob per phase).
+    """
+    capture_sizes = (
+        list(range(4, 33, 4))
+        + list(range(48, 257, 16))
+        + list(range(288, 513, 32))
+        + list(range(576, 1024 + 1, 64))
+        + list(range(1280, 4096 + 1, 256))
+        + list(range(4608, max_bs + 1, 512))
+    )
+
+    capture_sizes = [s for s in capture_sizes if s <= max_bs]
+
+    return capture_sizes
+
+
+def generate_decode_cuda_graph_batch_sizes(server_args: Any, max_bs: int):
+    """
+    Generate the list of batch sizes for CUDA graph capture based on max_bs.
+    This integrates the logic from cuda_graph_runner.py.
+    """
+    cfg = resolving_view(server_args)
+    # Handle disable_cuda_graph_padding as the first condition for both spec and non-spec
+    if cfg.disable_cuda_graph_padding:
+        capture_bs = list(range(1, max_bs + 1))
+    elif cfg.speculative_algorithm is None:
+        # Normal case:
+        capture_bs = (
+            [1, 2, 4, 8, 12]
+            + list(range(16, 257, 8))
+            + list(range(272, 512, 16))
+            + list(range(512, max_bs + 1, 32))
+        )
+    else:
+        # Spec decoding case: less padding for smaller batch sizes
+        capture_bs = (
+            list(range(1, 9, 1))
+            + list(range(10, 33, 2))
+            + list(range(40, 65, 4))
+            + list(range(72, 257, 8))
+            + list(range(272, max_bs + 1, 16))
+        )
+
+    capture_bs = [bs for bs in capture_bs if bs <= max_bs]
+
+    if max_bs not in capture_bs:
+        capture_bs.append(max_bs)
+
+    return capture_bs
+
+
+def generate_cpu_graph_batch_sizes(server_args: Any):
+    """
+    Generate the list of batch sizes for CPU graph capture based on torch_compile_max_bs.
+    """
+    cfg = resolving_view(server_args)
+    if cfg.disable_cuda_graph_padding:
+        capture_bs = list(range(1, cfg.torch_compile_max_bs + 1))
+    else:
+        capture_bs = sorted(
+            set().union(
+                range(1, 17),
+                range(18, 31, 2),
+                range(32, 81, 4),
+                range(84, cfg.torch_compile_max_bs + 1, 8),
+                {cfg.torch_compile_max_bs},
+            )
+        )
+    capture_bs = [bs for bs in capture_bs if bs <= cfg.torch_compile_max_bs]
+
+    return capture_bs
+
+
+def apply_cuda_graph_disaggregation_roles(server_args: Any):
+    cfg = resolving_view(server_args)
+    if cfg.disaggregation_mode == "prefill":
+        if (Phase.DECODE, "backend") not in server_args._cuda_graph_config_locked:
+            declare_resolution(
+                server_args,
+                "_apply_cuda_graph_disaggregation_roles",
+                cuda_graph_config=with_phase(
+                    cfg.cuda_graph_config, Phase.DECODE, backend=Backend.DISABLED
+                ),
+            )
+    elif cfg.disaggregation_mode == "decode":
+        if (Phase.PREFILL, "backend") not in server_args._cuda_graph_config_locked:
+            declare_resolution(
+                server_args,
+                "_apply_cuda_graph_disaggregation_roles",
+                cuda_graph_config=with_phase(
+                    cfg.cuda_graph_config, Phase.PREFILL, backend=Backend.DISABLED
+                ),
+            )

python/sglang/srt/arg_groups/expert_pack_hook.py

@@ -27,6 +27,8 @@ logger = logging.getLogger(__name__)
 
 def handle_expert_pack(server_args: Any) -> None:
     """Normalize expert-pack settings and report all startup errors together."""
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if cfg.load_format != "expert_pack":
         return
@@ -146,7 +148,7 @@ def handle_expert_pack(server_args: Any) -> None:
             )
         else:
             try:
-                hf_config = server_args.get_model_config().hf_config
+                hf_config = model_config_of(server_args).hf_config
             except Exception as exc:
                 errors.append(f"failed to load expert_pack model config: {exc}")
             else:

python/sglang/srt/arg_groups/hicache_hook.py

@@ -68,6 +68,8 @@ def handle_hicache_ratio_default(server_args: Any):
 
 
 def resolve_hicache_dcp_compatibility(server_args: Any):
+    from sglang.srt.arg_groups.overrides import use_mla_backend
+
     cfg = resolving_view(server_args)
     if cfg.dcp_size <= 1 or not cfg.enable_hierarchical_cache:
         return
@@ -95,7 +97,7 @@ def resolve_hicache_dcp_compatibility(server_args: Any):
             "--enable-hisparse with --dcp-size > 1 is not supported: the "
             "HiSparse host pool is constructed without DCP translation."
         )
-    if not server_args.use_mla_backend():
+    if not use_mla_backend(server_args):
         raise NotImplementedError(
             "HiCache with --dcp-size > 1 is only supported for MLA models: "
             "the index translation lives in MLATokenToKVPoolHost, and the "

python/sglang/srt/arg_groups/hisparse_hook.py

@@ -19,7 +19,8 @@ HISPARSE_KV_CACHE_DTYPES = ("bfloat16", "fp8_e4m3")
 
 
 def _is_hip() -> bool:
-    from sglang.srt.server_args import is_hip
+    """The one place this family asks about ROCm, and the seam the tests patch."""
+    from sglang.srt.utils.common import is_hip
 
     return is_hip()
 
@@ -81,6 +82,8 @@ def validate_hisparse_kv_cache_dtype(server_args: ServerArgs) -> None:
 
 def validate_hisparse(server_args: ServerArgs) -> None:
     """Validate --enable-hisparse constraints (model class, radix cache, DSA backend)."""
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if not cfg.enable_hisparse:
         return
@@ -90,7 +93,7 @@ def validate_hisparse(server_args: ServerArgs) -> None:
         is_deepseek_v4,
     )
 
-    hf_config = server_args.get_model_config().hf_config
+    hf_config = model_config_of(server_args).hf_config
     is_v4_hisparse = is_deepseek_v4(hf_config)
     is_hip = _is_hip()
     assert is_deepseek_dsa(hf_config) or is_v4_hisparse, (

python/sglang/srt/arg_groups/kv_cache_hook.py

@@ -37,13 +37,15 @@ def handle_mxfp8_kv_cache_compatibility(server_args: Any) -> None:
 
 def handle_kv4_compatibility(server_args: Any) -> None:
     """Check FP4 KV cache compatibility with the attention backend"""
+    from sglang.srt.arg_groups.overrides import attention_backends_of, use_mla_backend
+
     cfg = resolving_view(server_args)
 
     if cfg.kv_cache_dtype not in ("nvfp4", "fp4_mx_block16"):
         return
 
-    use_mla_backend = server_args.use_mla_backend()
-    prefill_backend, decode_backend = server_args._resolved_attention_backends()
+    uses_mla = use_mla_backend(server_args)
+    prefill_backend, decode_backend = attention_backends_of(resolved_view(server_args))
     attention_backend = resolved_view(server_args).attention_backend
 
     if is_cuda():
@@ -64,7 +66,7 @@ def handle_kv4_compatibility(server_args: Any) -> None:
             )
         else:
             if prefill_backend == "fa4":
-                if use_mla_backend:  # FA4 + MLA
+                if uses_mla:  # FA4 + MLA
                     KV4_FA4_MLA_BACKEND_CHOICES = [
                         "cutlass_mla",
                         "flashinfer",
@@ -85,7 +87,7 @@ def handle_kv4_compatibility(server_args: Any) -> None:
                         f"{KV4_FA4_MHA_BACKEND_CHOICES}, but got {decode_backend}"
                     )
             else:
-                if use_mla_backend:  # !FA4 + MLA
+                if uses_mla:  # !FA4 + MLA
                     KV4_ATTENTION_MLA_BACKEND_CHOICES = [
                         "cutlass_mla",
                         "flashinfer",
@@ -120,6 +122,8 @@ def handle_prefill_only_disable_kv_cache(server_args: Any) -> None:
     still None, backends haven't settled yet and the resolved (prefill,
     decode) pair would be a stale (None, None).
     """
+    from sglang.srt.arg_groups.overrides import attention_backends_of
+
     cfg = resolving_view(server_args)
 
     if not cfg.prefill_only_disable_kv_cache:
@@ -130,7 +134,7 @@ def handle_prefill_only_disable_kv_cache(server_args: Any) -> None:
         "_handle_attention_backend_compatibility() so the prefill backend is resolved."
     )
 
-    prefill_backend, _ = server_args._resolved_attention_backends()
+    prefill_backend, _ = attention_backends_of(resolved_view(server_args))
     if prefill_backend not in ("fa3", "fa4"):
         raise ValueError(
             "--prefill-only-disable-kv-cache currently requires the FA prefill backend "
@@ -194,6 +198,8 @@ def handle_cache_compatibility(server_args: Any) -> None:
 
 
 def handle_unified_memory_pool(server_args: Any) -> None:
+    from sglang.srt.arg_groups.overrides import attention_backends_of
+
     cfg = resolving_view(server_args)
     if not cfg.enable_unified_memory:
         return
@@ -236,7 +242,7 @@ def handle_unified_memory_pool(server_args: Any) -> None:
         # Both roles: verify routes to either backend depending on
         # --speculative-attention-mode.
         spec_allowed = {"triton", "trtllm_mla", "cutedsl_mla", "tokenspeed_mla"}
-        spec_backends = set(server_args._resolved_attention_backends())
+        spec_backends = set(attention_backends_of(resolved_view(server_args)))
         spec_backends.discard(None)
         assert spec_backends <= spec_allowed, (
             "--enable-unified-memory + DSPARK requires spec-verify-audited "
@@ -273,6 +279,8 @@ def handle_page_major_kv_layout(server_args: Any):
     # The unified pool stores state in the page-major envelope-strided layout, so
     # enabling it implies --enable-page-major-kv-layout — routing it through the
     # single page-major path + stride-aware Triton asserts (set before the guard).
+    from sglang.srt.arg_groups.overrides import attention_backends_of, use_mla_backend
+
     cfg = resolving_view(server_args)
     if cfg.enable_unified_memory:
         declare_resolution(
@@ -287,14 +295,14 @@ def handle_page_major_kv_layout(server_args: Any):
     # exposes each layer as a DENSE contiguous per-layer view
     # (build_dense_mla_views), which the paged MLA kernels consume directly,
     # with their kv_indices / block tables remapped to dense ids. Names below
-    # are the RESOLVED ids from _resolved_attention_backends: "flashinfer" is
+    # are the RESOLVED ids from attention_backends_of: "flashinfer" is
     # FlashInferMLAAttnBackend for an MLA model, "trtllm_mla" the trtllm
     # decode kernel; "cutedsl_mla" and "tokenspeed_mla" subclass
     # TRTLLMMLABackend and inherit its dense read/write path; "fa3" remaps its
     # page_table (in-kernel for captured decode, one funnel for eager).
     # flashmla / cutlass_mla share the create_flashmla block-table path and
     # can be added the same way once exercised.
-    if cfg.enable_unified_memory and server_args.use_mla_backend():
+    if cfg.enable_unified_memory and use_mla_backend(server_args):
         allowed_full = {
             "triton",
             "fa3",
@@ -305,7 +313,7 @@ def handle_page_major_kv_layout(server_args: Any):
         }
     else:
         allowed_full = {"triton"}
-    backends = set(server_args._resolved_attention_backends())
+    backends = set(attention_backends_of(resolved_view(server_args)))
     backends.discard(None)
     assert backends <= allowed_full, (
         "--enable-page-major-kv-layout requires the Triton attention backend "
@@ -327,7 +335,7 @@ def handle_page_major_kv_layout(server_args: Any):
     # are MLA-hybrid) from GDN models (GQA-hybrid) for the KDA-only caveat.
     decode_allowed = {"triton", "flashinfer"}
     prefill_allowed = {"triton", "flashkda"}
-    if server_args.use_mla_backend():
+    if use_mla_backend(server_args):
         decode_allowed.update({"cutedsl", "helion"})
         prefill_allowed.update({"cutedsl", "helion"})
     resolved_linear_decode = cfg.linear_attn_decode_backend or cfg.linear_attn_backend
@@ -403,7 +411,7 @@ def validate_prefill_only_disable_kv_cache_args(server_args: Any):
     # Context-parallel prefill stages K/V through cp_allgather_and_save_kv_cache,
     # which writes to the pool via set_kv_buffer. NoOpMHATokenToKVPool intentionally
     # raises on writes, so the engine would boot fine but fail on the first request.
-    if server_args._resolved().attn_cp_size > 1:
+    if resolved_view(server_args).attn_cp_size > 1:
         raise ValueError(
             "--prefill-only-disable-kv-cache is incompatible with --attn-cp-size > 1: "
             "the context-parallel attention path writes K/V to the pool via set_kv_buffer, "

python/sglang/srt/arg_groups/lora_hook.py

@@ -7,6 +7,7 @@ import logging
 from typing import Any
 
 from sglang.srt.arg_groups.overrides import (
+    declare_late_resolution,
     resolving_view,
 )
 from sglang.srt.environ import envs
@@ -23,7 +24,9 @@ def check_lora_server_args(server_args: Any):
     # Enable LoRA if any LoRA paths are provided for backward compatibility.
     if cfg.lora_paths:
         if cfg.enable_lora is None:
-            server_args._late_resolution("check_lora_server_args", enable_lora=True)
+            declare_late_resolution(
+                server_args, "check_lora_server_args", enable_lora=True
+            )
             logger.warning(
                 "--enable-lora is set to True because --lora-paths is provided."
             )
@@ -34,8 +37,8 @@ def check_lora_server_args(server_args: Any):
 
     if cfg.enable_lora:
         if cfg.enable_lora_overlap_loading is None:
-            server_args._late_resolution(
-                "check_lora_server_args", enable_lora_overlap_loading=False
+            declare_late_resolution(
+                server_args, "check_lora_server_args", enable_lora_overlap_loading=False
             )
 
         if cfg.enable_lora_overlap_loading:
@@ -90,11 +93,12 @@ def check_lora_server_args(server_args: Any):
                         "Expected a string or a dictionary."
                     )
                 parsed_lora_paths.append(lora_ref)
-            server_args._late_resolution(
-                "check_lora_server_args", lora_paths=parsed_lora_paths
+            declare_late_resolution(
+                server_args, "check_lora_server_args", lora_paths=parsed_lora_paths
             )
         elif isinstance(cfg.lora_paths, dict):
-            server_args._late_resolution(
+            declare_late_resolution(
+                server_args,
                 "check_lora_server_args",
                 lora_paths=[
                     LoRARef(
@@ -107,7 +111,9 @@ def check_lora_server_args(server_args: Any):
                 ],
             )
         elif cfg.lora_paths is None:
-            server_args._late_resolution("check_lora_server_args", lora_paths=[])
+            declare_late_resolution(
+                server_args, "check_lora_server_args", lora_paths=[]
+            )
         else:
             raise ValueError(
                 f"Invalid type for --lora-paths: {type(cfg.lora_paths)}. "
@@ -117,7 +123,8 @@ def check_lora_server_args(server_args: Any):
         # Normalize target modules to a set; keep {"all"} as a sentinel
         # that gets resolved model-awarely in lora_manager.init_lora_shapes().
         if cfg.lora_target_modules:
-            server_args._late_resolution(
+            declare_late_resolution(
+                server_args,
                 "check_lora_server_args",
                 lora_target_modules=set(cfg.lora_target_modules),
             )

python/sglang/srt/arg_groups/memory_hook.py

@@ -9,9 +9,11 @@ from typing import Any
 
 from sglang.srt.arg_groups.overrides import (
     declare_resolution,
+    resolved_view,
     resolving_view,
 )
 from sglang.srt.environ import envs
+from sglang.srt.model_executor.cuda_graph_config import Backend
 
 logger = logging.getLogger(__name__)
 
@@ -40,6 +42,17 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
 
       The coefficient 1.5 is a heuristic value, in the future, we can do better estimation by looking at the model types, hidden sizes or even do a dummy run.
     """
+    from sglang.srt.arg_groups.cuda_graph_hook import (
+        generate_cpu_graph_batch_sizes,
+        generate_decode_cuda_graph_batch_sizes,
+        generate_prefill_cuda_graph_batch_sizes,
+    )
+    from sglang.srt.arg_groups.overrides import (
+        model_config_of,
+        post_capture_kv_sizing_planned,
+        use_mla_backend,
+    )
+
     cfg = resolving_view(server_args)
     # A copy, so an earlier declaration keeps the value it recorded.
     cuda_graph_config = copy.deepcopy(cfg.cuda_graph_config)
@@ -139,10 +152,8 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
     # Set cuda graph batch sizes
     if cfg.device != "cpu":
         if decode_cuda_graph_config.bs is None:
-            decode_cuda_graph_config.bs = (
-                server_args._generate_decode_cuda_graph_batch_sizes(
-                    decode_cuda_graph_config.max_bs
-                )
+            decode_cuda_graph_config.bs = generate_decode_cuda_graph_batch_sizes(
+                server_args, decode_cuda_graph_config.max_bs
             )
         else:
             decode_cuda_graph_config.max_bs = max(decode_cuda_graph_config.bs)
@@ -164,7 +175,7 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
                 torch_compile_max_bs=cfg.torch_compile_max_bs
                 or decode_cuda_graph_config.max_bs,
             )
-            decode_cuda_graph_config.bs = server_args._generate_cpu_graph_batch_sizes()
+            decode_cuda_graph_config.bs = generate_cpu_graph_batch_sizes(server_args)
 
         assert (
             cfg.torch_compile_max_bs > 0
@@ -175,7 +186,7 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
         # Refer to pr #15927, by default we set the prefill max_bs to the chunked prefill size.
         # For MLA backend, the introduction of piecewise cuda graph will influence the kernel dispatch difference compared to the original mode.
         # To avoid the performance regression, we set max_bs to 2048 by default.
-        if not server_args.use_mla_backend():
+        if not use_mla_backend(server_args):
             prefill_cuda_graph_config.max_bs = cfg.chunked_prefill_size
         else:
             prefill_cuda_graph_config.max_bs = 2048
@@ -194,10 +205,8 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
             )
 
     if prefill_cuda_graph_config.bs is None:
-        prefill_cuda_graph_config.bs = (
-            server_args._generate_prefill_cuda_graph_batch_sizes(
-                prefill_cuda_graph_config.max_bs
-            )
+        prefill_cuda_graph_config.bs = generate_prefill_cuda_graph_batch_sizes(
+            server_args, prefill_cuda_graph_config.max_bs
         )
 
     if cuda_graph_config != cfg.cuda_graph_config:
@@ -208,7 +217,7 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
         )
 
     if cfg.mem_fraction_static is None:
-        if server_args.post_capture_kv_sizing_planned():
+        if post_capture_kv_sizing_planned(server_args):
             # Post-capture sizing measures free memory after graph capture, so
             # skip the graph/activation reserve; keep only the floor + parallel slack.
             reserved_mem = 1536
@@ -230,11 +239,11 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
             reserved_mem += activation_tokens * 1.5
             # Some adjustments for large parallel size
             reserved_mem += cfg.tp_size * cfg.pp_size / 8 * 1024
-            reserved_mem += server_args.reserve_for_graph_mb()
+            reserved_mem += reserve_for_graph_mb(server_args)
             if gpu_mem is not None and gpu_mem > 60 * 1024:
                 reserved_mem = max(reserved_mem, 10 * 1024)
             # Reserve headroom for DeepEP all-to-all buffers on top of the floor.
-            reserved_mem += server_args.reserve_for_deepep_a2a_mb()
+            reserved_mem += reserve_for_deepep_a2a_mb(server_args)
 
         declare_resolution(
             server_args,
@@ -250,14 +259,14 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
         # so we adjust the mem_fraction_static accordingly. The VLM encoder
         # only runs on the prefill stage, so PD decode engines do not need
         # this headroom; prefill engines and normal (non-PD) engines do.
-        model_config = server_args.get_model_config()
+        model_config = model_config_of(server_args)
         if (
             model_config.is_multimodal
             and not cfg.language_only
             and not cfg.language_model_only
             and cfg.disaggregation_mode != "decode"
         ):
-            server_args.adjust_mem_fraction_for_vlm(model_config)
+            adjust_mem_fraction_for_vlm(server_args, model_config)
 
     # If symm mem is enabled and prealloc size is not set, set it to 4GB
     if cfg.enable_symm_mem and not envs.SGLANG_SYMM_MEM_PREALLOC_GB_SIZE.is_set():
@@ -266,3 +275,104 @@ def handle_gpu_memory_settings(server_args: Any, gpu_mem):
             "Symmetric memory is enabled, setting symmetric memory prealloc size to 4GB as default."
             "Use environment variable SGLANG_SYMM_MEM_PREALLOC_GB_SIZE to change the prealloc size."
         )
+
+
+def reserve_for_graph_mb(server_args: Any) -> float:
+    from sglang.srt.arg_groups.overrides import use_mla_backend
+
+    cfg = resolving_view(server_args)
+    decode_cuda_graph_config = cfg.cuda_graph_config.decode
+    prefill_cuda_graph_config = cfg.cuda_graph_config.prefill
+
+    reserved_mem = 0.0
+    if (
+        cfg.disaggregation_mode != "prefill"
+        and decode_cuda_graph_config.backend != Backend.DISABLED
+    ):
+        reserved_mem += decode_cuda_graph_config.max_bs * 2
+
+    if (
+        resolved_view(server_args).enable_dp_attention
+        and cfg.disaggregation_mode != "prefill"
+    ):
+        # DP attention needs more padding for some operations, and much more for large
+        # cuda graph max bs (torch allocator / implementation inefficiencies).
+        reserved_mem += decode_cuda_graph_config.max_bs * cfg.dp_size * 3
+        if decode_cuda_graph_config.max_bs > 300:
+            reserved_mem += decode_cuda_graph_config.max_bs * cfg.dp_size * 1.5
+
+    if (
+        cfg.disaggregation_mode != "decode"
+        and prefill_cuda_graph_config.backend != Backend.DISABLED
+    ):
+        if not use_mla_backend(server_args):
+            # Only non-torch memory is counted; torch memory is reused by cuda graph capture.
+            reserved_mem += len(prefill_cuda_graph_config.bs) * 8
+        else:
+            # MLA backend overhead is much higher than expected with fa3.
+            reserved_mem += 1.5 * 1024
+
+        if (
+            prefill_cuda_graph_config.backend == Backend.BREAKABLE
+            and resolved_view(server_args).moe_a2a_backend == "deepep"
+        ):
+            # Prefill-BCG DeepEP delta (bridge pool + NVL first-touch
+            # during capture); decode-side DeepEP is a baseline cost.
+            reserved_mem += 1 * 1024
+
+    return reserved_mem
+
+
+def reserve_for_deepep_a2a_mb(server_args: Any) -> float:
+    # DeepEP all-to-all buffers captured in the decode graph are real extra
+    # allocations, reserved on top of the floor.
+
+    cfg = resolving_view(server_args)
+    decode_cuda_graph_config = cfg.cuda_graph_config.decode
+    if (
+        cfg.disaggregation_mode != "prefill"
+        and decode_cuda_graph_config.backend != Backend.DISABLED
+        and resolved_view(server_args).moe_a2a_backend == "deepep"
+    ):
+        return 2 * 1024
+    return 0.0
+
+
+def adjust_mem_fraction_for_vlm(server_args: Any, model_config):
+    cfg = resolving_view(server_args)
+    vision_config = getattr(model_config.hf_config, "vision_config", None)
+    if vision_config is None:
+        return
+
+    # roughly reduce the mem_fraction_static base on params of Vit
+    original_server_arg_mem_fraction = cfg.mem_fraction_static
+    # a base mem_fraction_static factor for regular Vit
+    base_mem_fraction_reduction_ratio = 0.95
+
+    vit_num_layers = getattr(vision_config, "num_hidden_layers", 24)
+    vit_hidden_size = getattr(vision_config, "hidden_size", 1024)
+
+    # baseline ViT params (ViT-L/14)
+    baseline_vit_layers = 24
+    baseline_vit_hidden_size = 1024
+
+    # weight params count
+    current_complexity_score = vit_num_layers * (vit_hidden_size**2)
+    baseline_complexity_score = baseline_vit_layers * (baseline_vit_hidden_size**2)
+    complexity_ratio = (
+        current_complexity_score / baseline_complexity_score
+        if baseline_complexity_score > 0
+        else 1.0
+    )
+
+    # every time the complexity grows 100%, adjust final factor for 10%
+    sensitivity_scale = 0.1
+    dynamic_adjustment_factor = 1.0 - sensitivity_scale * (complexity_ratio - 1.0)
+    dynamic_adjustment_factor = max(0.8, min(1.05, dynamic_adjustment_factor))
+
+    final_overall_factor = base_mem_fraction_reduction_ratio * dynamic_adjustment_factor
+    declare_resolution(
+        server_args,
+        "adjust_mem_fraction_for_vlm",
+        mem_fraction_static=original_server_arg_mem_fraction * final_overall_factor,
+    )

python/sglang/srt/arg_groups/model_hook.py

@@ -8,6 +8,7 @@ from typing import Any
 
 from sglang.srt.arg_groups.overrides import (
     declare_resolution,
+    mamba_cache_chunk_size,
     resolved_view,
     resolving_view,
 )
@@ -34,6 +35,12 @@ logger = logging.getLogger(__name__)
 
 
 def handle_model_specific_adjustments(server_args: Any):
+    from sglang.srt.arg_groups.overrides import (
+        attention_backends_of,
+        model_config_of,
+        use_mla_backend,
+    )
+
     cfg = resolving_view(server_args)
     from sglang.srt.configs.model_config import (
         get_mimo_v2_fused_qkv_expected_tp_size,
@@ -57,7 +64,7 @@ def handle_model_specific_adjustments(server_args: Any):
         # key them on.
         return
 
-    model_config = server_args.get_model_config()
+    model_config = model_config_of(server_args)
     hf_config = model_config.hf_config
     model_arch = hf_config.architectures[0]
 
@@ -203,10 +210,14 @@ def handle_model_specific_adjustments(server_args: Any):
                 import torch
 
                 major, _ = torch.cuda.get_device_capability()
-                server_args._set_default_dsa_kv_cache_dtype(
-                    major, resolved_view(server_args).quantization
+                from sglang.srt.arg_groups.overrides import (
+                    _dsa_kv_cache_dtype_default,
+                    _dsa_split_backend_resolution,
+                    run_post_process_pass,
                 )
-                server_args._set_default_dsa_backends(major)
+
+                run_post_process_pass(server_args, _dsa_kv_cache_dtype_default)
+                run_post_process_pass(server_args, _dsa_split_backend_resolution)
 
             if cfg.enable_prefill_cp:
                 assert (
@@ -270,7 +281,7 @@ def handle_model_specific_adjustments(server_args: Any):
             # MLA prefill CP auto-config: the field declarations moved to
             # the override registry (arg_groups/overrides.py:
             # _deepseek_family_overrides).
-            if cfg.enable_prefill_cp and server_args.use_mla_backend():
+            if cfg.enable_prefill_cp and use_mla_backend(server_args):
                 declare_resolution(
                     server_args,
                     "_handle_model_specific_adjustments",
@@ -304,7 +315,7 @@ def handle_model_specific_adjustments(server_args: Any):
                 # here for the rest of the DSA family (DeepSeek-V3.2 /
                 # GLM-5.x) that shares the same decode top-k path.
                 envs.SGLANG_OPT_USE_TOPK_V2.set(False)
-            if not server_args._resolved().enable_dp_attention and cfg.nnodes == 1:
+            if not resolved_view(server_args).enable_dp_attention and cfg.nnodes == 1:
                 # TODO (Hubert): Put this back later
                 # server_args.enable_aiter_allreduce_fusion = True
                 logger.info("Enable Aiter AllReduce Fusion for DeepseekV3ForCausalLM")
@@ -372,8 +383,8 @@ def handle_model_specific_adjustments(server_args: Any):
                 "intel_xpu",
                 "aiter",
             ]
-            prefill_attn_backend, decode_attn_backend = (
-                server_args._resolved_attention_backends()
+            prefill_attn_backend, decode_attn_backend = attention_backends_of(
+                resolved_view(server_args)
             )
             assert (
                 prefill_attn_backend in supported_backends
@@ -387,7 +398,7 @@ def handle_model_specific_adjustments(server_args: Any):
         quant_method = get_quantization_config(hf_config)
         is_mxfp4_quant_format = quant_method == "mxfp4"
         if (
-            not server_args._resolved().enable_dp_attention
+            not resolved_view(server_args).enable_dp_attention
             and cfg.nnodes == 1
             and is_hip()
         ):
@@ -407,13 +418,13 @@ def handle_model_specific_adjustments(server_args: Any):
 
         if resolved_view(server_args).moe_runner_backend == "triton_kernel":
             assert (
-                server_args._resolved().ep_size == 1
+                resolved_view(server_args).ep_size == 1
             ), "Triton kernel MoE is only supported when ep_size == 1"
 
     elif model_arch in ("MiMoV2ForCausalLM", "MiMoV2FlashForCausalLM"):
         if model_arch == "MiMoV2ForCausalLM" and not cfg.encoder_only:
             expected_attn_tp_size = get_mimo_v2_fused_qkv_expected_tp_size(hf_config)
-            view = server_args._resolved()
+            view = resolved_view(server_args)
             attn_dp_size = cfg.dp_size if view.enable_dp_attention else 1
             effective_attn_tp_size = cfg.tp_size // attn_dp_size // view.attn_cp_size
             if (
@@ -476,7 +487,9 @@ def handle_model_specific_adjustments(server_args: Any):
     ):
         # Default attention backend selection moved to the override registry
         # (arg_groups/overrides.py: _gemma4_overrides).
-        prefill_backend, decode_backend = server_args._resolved_attention_backends()
+        prefill_backend, decode_backend = attention_backends_of(
+            resolved_view(server_args)
+        )
         accepted_backends = (
             "trtllm_mha",
             "triton",
@@ -585,9 +598,13 @@ def handle_model_specific_adjustments(server_args: Any):
 
 
 def handle_model_capability_adjustments(server_args: Any):
+    from sglang.srt.arg_groups.cuda_graph_hook import (
+        generate_prefill_cuda_graph_batch_sizes,
+    )
     from sglang.srt.arg_groups.kv_cache_hook import (
         validate_prefill_only_disable_kv_cache_args,
     )
+    from sglang.srt.arg_groups.overrides import model_config_of
 
     cfg = resolving_view(server_args)
     if parse_connector_type(cfg.model_path) == ConnectorType.INSTANCE:
@@ -597,7 +614,7 @@ def handle_model_capability_adjustments(server_args: Any):
         run_post_process_pass,
     )
 
-    model_config = server_args.get_model_config()
+    model_config = model_config_of(server_args)
     hf_config = model_config.hf_config
 
     # HRM-Text needs bidirectional prompt attention (prefill), which only
@@ -768,8 +785,8 @@ def handle_model_capability_adjustments(server_args: Any):
                     )
                 }
                 if (Phase.PREFILL, "bs") not in cuda_graph_config_locked:
-                    sizing["bs"] = server_args._generate_prefill_cuda_graph_batch_sizes(
-                        sizing["max_bs"]
+                    sizing["bs"] = generate_prefill_cuda_graph_batch_sizes(
+                        server_args, sizing["max_bs"]
                     )
                 declare_resolution(
                     server_args,
@@ -831,13 +848,15 @@ def handle_mamba_radix_cache(server_args: Any, model_arch: str):
         validate_mamba_extra_buffer(
             view,
             model_arch,
-            mamba_cache_chunk_size_of=lambda: server_args.mamba_cache_chunk_size,
+            mamba_cache_chunk_size_of=lambda: mamba_cache_chunk_size(server_args),
         )
     else:
         validate_mamba_no_buffer(view, model_arch)
 
 
 def handle_language_model_only(server_args: Any):
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if not cfg.language_model_only:
         return
@@ -858,7 +877,7 @@ def handle_language_model_only(server_args: Any):
             "--language-model-only is incompatible with --disaggregation-mode "
             "prefill/decode"
         )
-    architectures = server_args.get_model_config().hf_config.architectures
+    architectures = model_config_of(server_args).hf_config.architectures
     if not any(
         a in server_args.LANGUAGE_MODEL_ONLY_ARCHITECTURES for a in architectures
     ):

python/sglang/srt/arg_groups/model_path_hook.py

@@ -3,6 +3,7 @@
 
 from __future__ import annotations
 
+import glob
 import importlib
 import logging
 import os
@@ -177,7 +178,7 @@ def handle_load_format(server_args: Any):
             load_format="gguf",
         )
 
-    if cfg.load_format == "auto" and server_args._is_mistral_native_format():
+    if cfg.load_format == "auto" and is_mistral_native_format(server_args):
         declare_resolution(
             server_args,
             "_handle_load_format",
@@ -306,3 +307,62 @@ def validate_transfer_engine(server_args: Any):
         return False
     else:
         return True
+
+
+def is_mistral_native_format(server_args: Any) -> bool:
+    """True iff the checkpoint requires load_format=mistral.
+
+    Looks for consolidated*.safetensors with no competing
+    model*.safetensors; when both weight formats ship in the
+    same checkpoint (e.g. Mistral-7B-Instruct-v0.3) the HF path is
+    preferred to avoid loading Mistral-named weights into an
+    HF-named architecture.
+
+    Name override: mistral-large-3 / mistral-small-4 /
+    leanstral always treat as Mistral-native when params.json
+    is present -- those families need Mistral weight loading
+    regardless of which weight files happen to be present.
+    """
+    cfg = resolving_view(server_args)
+    _MISTRAL_NATIVE_PATTERNS = (
+        "mistral-large-3",
+        "mistral-small-4",
+        "leanstral",
+    )
+    name_matches = any(
+        p in str(cfg.model_path).lower() for p in _MISTRAL_NATIVE_PATTERNS
+    )
+
+    def _check_format(has_params, has_consolidated, has_hf_weights) -> bool:
+        if has_params and name_matches:
+            return True
+        return has_consolidated and not has_hf_weights
+
+    if os.path.isdir(cfg.model_path):
+        return _check_format(
+            has_params=os.path.exists(os.path.join(cfg.model_path, "params.json")),
+            has_consolidated=bool(
+                glob.glob(os.path.join(cfg.model_path, "consolidated*.safetensors"))
+            ),
+            has_hf_weights=bool(
+                glob.glob(os.path.join(cfg.model_path, "model*.safetensors"))
+            ),
+        )
+
+    try:
+        from huggingface_hub import HfApi
+
+        files = {s.rfilename for s in HfApi().model_info(cfg.model_path).siblings}
+        return _check_format(
+            has_params="params.json" in files,
+            has_consolidated=any(
+                f.startswith("consolidated") and f.endswith(".safetensors")
+                for f in files
+            ),
+            has_hf_weights=any(
+                f.startswith("model") and f.endswith(".safetensors") and "/" not in f
+                for f in files
+            ),
+        )
+    except Exception:
+        return False

python/sglang/srt/arg_groups/moe_hook.py

@@ -8,7 +8,10 @@ import os
 from typing import Any
 
 from sglang.srt.arg_groups.overrides import (
+    cutedsl_moe_max_num_tokens,
     declare_resolution,
+    max_prefill_buffer_tokens,
+    max_speculative_num_draft_tokens,
     resolved_view,
     resolving_view,
 )
@@ -24,6 +27,8 @@ def handle_moe_kernel_config(server_args: Any):
     # The quantization-driven runner resolutions moved to the pipeline
     # (arg_groups/overrides.py: _moe_runner_backend_quant_constraints);
     # the compatibility asserts and fusion writes stay below.
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     from sglang.srt.arg_groups.overrides import (
         _moe_runner_backend_quant_constraints,
@@ -50,7 +55,7 @@ def handle_moe_kernel_config(server_args: Any):
         # modelopt_mixed with non-NVFP4 MoE layers is rejected at load time.
         assert (
             view.quantization in ["modelopt_fp4", "modelopt_mixed", "nvfp4_online"]
-            or server_args.get_model_config().nvfp4_moe_meta is not None
+            or model_config_of(server_args).nvfp4_moe_meta is not None
         ), f"Invalid quantization '{view.quantization}'. \nFlashInfer CuteDSL MOE currently supports only: 'modelopt_fp4', 'modelopt_mixed' (with NVFP4 MoE layers), 'nvfp4_online', or hybrid NVFP4 models."
         assert view.ep_size in [
             1,
@@ -116,6 +121,8 @@ def handle_a2a_moe(server_args: Any):
     # the resolution pipeline (arg_groups/overrides.py:
     # _a2a_backend_overrides / _a2a_ep_size); the per-backend logs,
     # asserts, fusion/deepep_mode/env/cuda-graph writes stay below.
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     from sglang.srt.arg_groups.overrides import (
         _a2a_backend_overrides,
@@ -259,7 +266,7 @@ def handle_a2a_moe(server_args: Any):
             logger.warning("--deepep-mode is ignored for Flashinfer MoE A2A")
         if not envs.SGLANG_MOE_NVFP4_DISPATCH.is_set() and (
             resolved_view(server_args).quantization == "modelopt_fp4"
-            or server_args.get_model_config().nvfp4_moe_meta is not None
+            or model_config_of(server_args).nvfp4_moe_meta is not None
         ):
             envs.SGLANG_MOE_NVFP4_DISPATCH.set(True)
             logger.warning(
@@ -291,7 +298,7 @@ def handle_a2a_moe(server_args: Any):
         # Skip validation if disaggregation mode is decode.
         if cfg.chunked_prefill_size > 0 and cfg.disaggregation_mode != "decode":
             assert (
-                server_args._required_mori_dispatch_tokens_per_rank()
+                required_mori_dispatch_tokens_per_rank(server_args)
             ) <= envs.SGLANG_MORI_NUM_MAX_DISPATCH_TOKENS_PER_RANK.get(), (
                 "SGLANG_MORI_NUM_MAX_DISPATCH_TOKENS_PER_RANK (default 4096) "
                 "must be >= the per-rank MoRI dispatch tokens "
@@ -339,7 +346,7 @@ def handle_a2a_moe(server_args: Any):
         # Skip validation if disaggregation mode is decode
         if cfg.chunked_prefill_size > 0 and cfg.disaggregation_mode != "decode":
             assert (
-                server_args._required_pplx_dispatch_tokens_per_rank()
+                required_pplx_dispatch_tokens_per_rank(server_args)
             ) <= envs.SGLANG_PPLX_NUM_MAX_DISPATCH_TOKENS_PER_RANK.get(), (
                 "SGLANG_PPLX_NUM_MAX_DISPATCH_TOKENS_PER_RANK (default 128) "
                 "must be >= the per-rank pplx dispatch tokens "
@@ -372,7 +379,7 @@ def validate_deepep_v2_dispatch_token_budget(server_args: Any) -> None:
 
     capacity = envs.SGLANG_DEEPEP_V2_NUM_MAX_DISPATCH_TOKENS_PER_RANK.get()
     if view.disaggregation_mode != "decode":
-        prefill_tokens = server_args.max_prefill_buffer_tokens() or (
+        prefill_tokens = max_prefill_buffer_tokens(server_args) or (
             view.max_prefill_tokens or 0
         )
         if prefill_tokens > capacity:
@@ -396,7 +403,7 @@ def validate_deepep_v2_dispatch_token_budget(server_args: Any) -> None:
         per_rank_pool_bs = max(1, view.max_running_requests // attn_dp_size)
         graph_bs = min(graph_bs, per_rank_pool_bs)
     tokens_per_req = (
-        server_args.max_speculative_num_draft_tokens or 1
+        max_speculative_num_draft_tokens(server_args) or 1
         if view.speculative_algorithm
         else 1
     )
@@ -413,6 +420,8 @@ def validate_deepep_v2_dispatch_token_budget(server_args: Any) -> None:
 
 def validate_deepep_v2_model_architecture(server_args: Any) -> None:
     """Allow DeepEP v2 only where its model workflow is validated."""
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     if (
         parse_connector_type(resolved_view(server_args).model_path)
         == ConnectorType.INSTANCE
@@ -424,7 +433,7 @@ def validate_deepep_v2_model_architecture(server_args: Any) -> None:
         )
 
     architectures = (
-        getattr(server_args.get_model_config().hf_config, "architectures", None) or []
+        getattr(model_config_of(server_args).hf_config, "architectures", None) or []
     )
 
     architecture = architectures[0] if architectures else None
@@ -458,7 +467,7 @@ def validate_cutedsl_a2a_token_budget(server_args: Any):
         and cfg.disaggregation_mode != "decode"
     ):
         return
-    required_tokens = server_args.cutedsl_moe_max_num_tokens()
+    required_tokens = cutedsl_moe_max_num_tokens(server_args)
     max_dispatch_tokens_per_rank = (
         envs.SGLANG_FLASHINFER_NUM_MAX_DISPATCH_TOKENS_PER_RANK.get() or 1024
     )
@@ -481,3 +490,18 @@ def validate_cutedsl_a2a_token_budget(server_args: Any):
             f"{required_per_rank}` or lower the relevant limit "
             f"(e.g. --max-prefill-tokens) to <= {max_cutedsl_tokens}."
         )
+
+
+def required_mori_dispatch_tokens_per_rank(server_args: Any) -> int:
+    """Max tokens a single rank dispatches through MoRI in one forward."""
+    cfg = resolving_view(server_args)
+    return cfg.chunked_prefill_size
+
+
+def required_pplx_dispatch_tokens_per_rank(server_args: Any) -> int:
+    """Max tokens a single rank dispatches through pplx in one forward."""
+    cfg = resolving_view(server_args)
+    required = cfg.chunked_prefill_size
+    if cfg.cuda_graph_max_bs_decode is not None:
+        required = max(required, cfg.cuda_graph_max_bs_decode)
+    return required

python/sglang/srt/arg_groups/overrides.py

@@ -38,12 +38,14 @@ import dataclasses
 import inspect
 import json
 import logging
+import math
 from typing import Any, Callable, Dict, List, Optional, Sequence, Tuple
 
 from sglang.srt.arg_groups.arg_utils import field_names, resolvable_fields
 from sglang.srt.environ import envs
 from sglang.srt.hardware_backend.mlx.runtime import use_mlx
 from sglang.srt.model_executor.cuda_graph_config import Backend
+from sglang.srt.platforms import current_platform
 from sglang.srt.utils.common import (
     cpu_has_amx_support,
     get_device_capability,
@@ -57,9 +59,11 @@ from sglang.srt.utils.common import (
     is_flashinfer_available,
     is_gfx95_supported,
     is_hip,
+    is_hopper_with_cuda_12_3,
     is_mnnvl_fabric_device,
     is_mps,
     is_musa,
+    is_no_spec_infer_or_topk_one,
     is_npu,
     is_sm90_supported,
     is_sm100_supported,
@@ -94,7 +98,7 @@ def register_model_override(architecture: str):
     The decorated callable receives ``(server_args, hf_config)``, must not
     mutate either, and returns a ``{field: resolved_value}`` dict (possibly
     empty when nothing applies). Providers needing derived model data beyond
-    the HF config go through ``server_args.get_model_config()`` (cached,
+    the HF config go through ``model_config_of(server_args)`` (cached,
     read-only) — never anything mutating.
     """
 
@@ -293,7 +297,7 @@ def declare_resolution(server_args: Any, source: str, **fields: Any) -> None:
     The stash *is* the resolution result: the bags are projected from it,
     `resolution_result` answers from it, and no field is written. A resolver
     reading a field another resolver may have decided must read `resolving_view`
-    (or `ServerArgs._resolved()`), which
+    (or `resolved_view(server_args)`), which
     `test_resolution_reads_the_declarations` pins.
 
     For resolvers inside ``__post_init__``; launcher-stage resolution goes
@@ -460,8 +464,7 @@ def resolved_view(server_args: Any) -> ResolvedView:
     overlaid on the fields, snapshotted per call.
 
     For mid-resolution code that is not a pass (``__post_init__`` handlers and
-    hooks), and for the record's own members that must answer with what
-    resolution decided -- a declaration-only resolver (a model-specific
+    hooks) that must answer with what resolution decided -- a declaration-only resolver (a model-specific
     override, a registry entry) never writes the field, so a field read there
     answers with the raw input."""
     return ResolvedView(server_args, overlay=_declaration_overlay(server_args))
@@ -702,7 +705,7 @@ def _kimi_k3_overrides(server_args: Any, hf_config: Any) -> dict:
 
     if not (is_sm100_supported() and get_device_sm() in (100, 103)):
         return {}
-    backends_unset = server_args.is_attention_backend_not_set()
+    backends_unset = is_attention_backend_not_set(cfg)
     if cfg.speculative_algorithm != "DSPARK":
         if not backends_unset:
             return {}
@@ -809,7 +812,7 @@ def _deepseek_family_overrides(server_args: Any, hf_config: Any) -> dict:
 
     if is_deepseek_dsa(hf_config):  # DeepSeek 3.2/GLM 5
         # Set attention backend for DeepSeek
-        if server_args.is_attention_backend_not_set():
+        if is_attention_backend_not_set(cfg):
             overrides["attention_backend"] = "dsa"
             logger.info("Use dsa attention backend for DeepSeek with DSA.")
         if not is_npu() and not is_xpu():  # CUDA or ROCm GPU
@@ -882,7 +885,7 @@ def _deepseek_family_overrides(server_args: Any, hf_config: Any) -> dict:
                 )
         # MLA prefill CP auto-config. Mirrors the NSA CP block above
         # (minus the in-seq/round-robin mode split, which MLA CP does not support)
-        if cfg.enable_prefill_cp and server_args.use_mla_backend():
+        if cfg.enable_prefill_cp and use_mla_backend(server_args):
             logger.warning(
                 "MLA prefill context parallel is still experimental. "
                 "Verified on Hopper with the fa3 backend."
@@ -944,7 +947,7 @@ def _minimax_m2_overrides(server_args: Any, hf_config: Any) -> dict:
     if (
         is_sm100_supported()
         and cfg.moe_runner_backend == "auto"
-        and server_args.get_model_config().quantization == "modelopt_fp4"
+        and model_config_of(server_args).quantization == "modelopt_fp4"
     ):
         overrides["moe_runner_backend"] = "flashinfer_trtllm_routed"
         logger.info(
@@ -971,7 +974,7 @@ def _minimax_m3_overrides(server_args: Any, hf_config: Any) -> dict:
         quant_resolved = quant_method
 
     if is_hip():
-        if server_args.is_attention_backend_not_set():
+        if is_attention_backend_not_set(cfg):
             overrides["attention_backend"] = "triton"
         if cfg.moe_runner_backend == "auto" and quant_resolved == "mxfp8":
             overrides["moe_runner_backend"] = "triton"
@@ -994,7 +997,7 @@ def _minimax_m3_overrides(server_args: Any, hf_config: Any) -> dict:
         if not aiter_fusion_resolved and not envs.SGLANG_M3_ALLOW_CUSTOM_AR.get():
             overrides["disable_custom_all_reduce"] = True
     elif is_sm100_supported():
-        if server_args.is_attention_backend_not_set():
+        if is_attention_backend_not_set(cfg):
             if (
                 cfg.kv_cache_dtype == "fp8_e4m3"
                 and not envs.SGLANG_DISABLE_M3_FP8_ATTN_GEMM.get()
@@ -1025,7 +1028,7 @@ def _minimax_m3_overrides(server_args: Any, hf_config: Any) -> dict:
             f"moe_runner_backend={overrides.get('moe_runner_backend', cfg.moe_runner_backend)}."
         )
     elif is_sm90_supported():
-        if server_args.is_attention_backend_not_set():
+        if is_attention_backend_not_set(cfg):
             overrides["attention_backend"] = "fa3"
         page_resolved = cfg.page_size
         if (
@@ -1117,7 +1120,7 @@ def _gpt_oss_overrides(server_args: Any, hf_config: Any) -> dict:
     cfg = resolving_view(server_args)
     overrides: Dict[str, Any] = {}
     # Set attention backend for GPT-OSS
-    if server_args.is_attention_backend_not_set():
+    if is_attention_backend_not_set(cfg):
         if is_sm100_supported():
             overrides["attention_backend"] = "trtllm_mha"
         elif is_sm90_supported():
@@ -1254,7 +1257,7 @@ def _gemma4_overrides(server_args: Any, hf_config: Any) -> dict:
     cfg = resolving_view(server_args)
     overrides: Dict[str, Any] = {}
     default_attention_backend = "trtllm_mha" if is_sm100_supported() else "triton"
-    if server_args.is_attention_backend_not_set():
+    if is_attention_backend_not_set(cfg):
         logger.info(
             f"Use {default_attention_backend} as default attention backend for Gemma4"
         )
@@ -1265,7 +1268,7 @@ def _gemma4_overrides(server_args: Any, hf_config: Any) -> dict:
     elif cfg.attention_backend is None:
         overrides["attention_backend"] = default_attention_backend
     if is_sm100_supported() and cfg.moe_runner_backend == "auto":
-        if server_args.get_model_config().quantization == "modelopt_fp4":
+        if model_config_of(server_args).quantization == "modelopt_fp4":
             overrides["quantization"] = "modelopt_fp4"
             overrides["moe_runner_backend"] = "flashinfer_trtllm"
             logger.info(
@@ -1278,12 +1281,12 @@ def _gemma4_overrides(server_args: Any, hf_config: Any) -> dict:
 @_register_for("MossVLForConditionalGeneration")
 def _moss_vl_overrides(server_args: Any, hf_config: Any) -> dict:
     overrides: Dict[str, Any] = {}
-    if server_args.is_attention_backend_not_set():
+    if is_attention_backend_not_set(resolving_view(server_args)):
         overrides["prefill_attention_backend"] = "flashinfer"
         logger.info("Use flashinfer as default prefill attention backend for Moss-VL")
     prefill_backend = (
         overrides.get("prefill_attention_backend")
-        or server_args.get_attention_backends()[0]
+        or attention_backends_of(resolved_view(server_args))[0]
     )
     assert prefill_backend == "flashinfer", (
         "MossVLForConditionalGeneration requires flashinfer prefill "
@@ -1323,7 +1326,7 @@ def _minicpm_sala_overrides(server_args: Any, hf_config: Any) -> dict:
         if dense_decode is not None:
             overrides["decode_attention_backend"] = dense_decode
     elif has_sparse_attention:
-        uses_sparse_backend = cfg.is_attention_backend_not_set() or any(
+        uses_sparse_backend = is_attention_backend_not_set(cfg) or any(
             backend in ("minicpm_flashattn", "minicpm_flashinfer")
             for backend in (
                 cfg.attention_backend,
@@ -1335,7 +1338,7 @@ def _minicpm_sala_overrides(server_args: Any, hf_config: Any) -> dict:
             raise ValueError(
                 "MiniCPM sparse attention does not support PD disaggregation"
             )
-        if cfg.is_attention_backend_not_set():
+        if is_attention_backend_not_set(cfg):
             overrides["attention_backend"] = (
                 "minicpm_flashinfer"
                 if is_blackwell_supported()
@@ -1413,7 +1416,7 @@ def _deepseek_v4_overrides(server_args: Any, hf_config: Any) -> dict:
         logger.info(f"Setting swa_full_tokens_ratio to 0.1 for {model_arch}.")
 
     if cfg.moe_runner_backend == "auto":
-        model_config = server_args.get_model_config()
+        model_config = model_config_of(server_args)
         # nvidia/DeepSeek-V4-Pro-NVFP4 uses the routed TRT-LLM runner.
         if model_config.nvfp4_moe_meta is not None:
             overrides["moe_runner_backend"] = "flashinfer_trtllm_routed"
@@ -1477,7 +1480,7 @@ def _inkling_overrides(server_args: Any, hf_config: Any) -> dict:
     # supported default when the user left every attention-backend flag unset
     # (mirrors the MiniMax-M3 SM100 fa4-default above); an explicit
     # --attention-backend / --prefill/decode-attention-backend still wins.
-    if server_args.is_attention_backend_not_set():
+    if is_attention_backend_not_set(cfg):
         inkling_attn_backend = "fa4" if is_sm100_supported() else "triton"
         overrides["attention_backend"] = inkling_attn_backend
         logger.info(
@@ -1495,7 +1498,7 @@ def _nemotron_h_overrides(server_args: Any, hf_config: Any) -> dict:
     cache handling and the triton-backend assert stay in the arch branch)."""
     cfg = resolving_view(server_args)
     model_arch = hf_config.architectures[0]
-    model_config = server_args.get_model_config()
+    model_config = model_config_of(server_args)
     overrides: Dict[str, Any] = {}
 
     is_modelopt = model_config.quantization in [
@@ -1565,7 +1568,7 @@ def _nemotron_h_overrides(server_args: Any, hf_config: Any) -> dict:
         else:
             overrides["moe_runner_backend"] = "flashinfer_cutlass"
 
-    if is_blackwell_supported() and cfg.is_attention_backend_not_set():
+    if is_blackwell_supported() and is_attention_backend_not_set(cfg):
         if cfg.speculative_algorithm is not None:
             speculative_algorithm = cfg.speculative_algorithm.upper()
             if is_sm100_supported() and cfg.speculative_eagle_topk in (
@@ -1607,13 +1610,14 @@ def _qwen3_5_hybrid_overrides(server_args: Any, hf_config: Any) -> dict:
         return {}
     sm100_default_attn_backend = "triton"
     # trtllm_mha requires speculative_eagle_topk == 1 and page_size > 1.
-    # _get_default_attn_backend handles the eagle_topk check.
+    # get_default_attn_backend handles the eagle_topk check.
     # There is only one case where page_size=1 is required,
     # which is when radix cache is enabled and both extra_buffer
     # and spec decoding are disabled.
-    default_attn_backend = server_args._get_default_attn_backend(
-        use_mla_backend=server_args.use_mla_backend(),
-        model_config=server_args.get_model_config(),
+    default_attn_backend = get_default_attn_backend(
+        server_args,
+        use_mla_backend=use_mla_backend(server_args),
+        model_config=model_config_of(server_args),
     )
     # The mamba radix-cache pass runs before this dispatch: read the
     # declared strategy through the view (the legacy branch observed the
@@ -1746,7 +1750,7 @@ def _olmo2_overrides(server_args: Any, hf_config: Any) -> dict:
 def _step3p_overrides(server_args: Any, hf_config: Any) -> dict:
     cfg = resolving_view(server_args)
     overrides: Dict[str, Any] = {}
-    if server_args.is_attention_backend_not_set():
+    if is_attention_backend_not_set(cfg):
         if is_blackwell_supported():
             logger.info("Auto-select fa4 attention backend for Step3p7 on Blackwell.")
             overrides["attention_backend"] = "fa4"
@@ -1857,7 +1861,7 @@ def _mamba_radix_cache_resolution(view: Any) -> dict:
         get_linear_attn_spec_by_arch,
     )
 
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     model_arch = hf_config.architectures[0]
 
     in_branch = model_arch in _MAMBA_RADIX_CACHE_ARCHS
@@ -1895,7 +1899,7 @@ def _dsa_kv_cache_dtype_default(view: Any) -> dict:
     PRISTINE dsa split backends (their resolution runs after this pass)."""
     from sglang.srt.configs.model_config import is_deepseek_dsa
 
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     if hf_config.architectures[0] not in _DEEPSEEK_FAMILY_ARCHS:
         return {}
     if not is_deepseek_dsa(hf_config):
@@ -1965,7 +1969,7 @@ def _dsa_split_backend_resolution(view: Any) -> dict:
     capability. The hisparse arm takes precedence under --enable-hisparse."""
     from sglang.srt.configs.model_config import is_deepseek_dsa
 
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     if hf_config.architectures[0] not in _DEEPSEEK_FAMILY_ARCHS:
         return {}
     if not is_deepseek_dsa(hf_config):
@@ -2065,7 +2069,7 @@ def _deepseek_moe_quant_resolution(view: Any) -> dict:
     backend for DeepSeek"), NOT a dispatch-time declaration: the DSA
     kv-cache-dtype default earlier in the branch must read the PRISTINE
     quantization, so this resolution has to stay at its legacy slot."""
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     model_arch = hf_config.architectures[0]
     if model_arch not in _DEEPSEEK_FAMILY_ARCHS:
         return {}
@@ -2152,7 +2156,7 @@ def _deepseek_spec_moe_resolution(view: Any) -> dict:
     quantization (after _deepseek_moe_quant_resolution) and the pre-a2a
     ep_size, exactly like the legacy in-branch writes."""
 
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     model_arch = hf_config.architectures[0]
     if model_arch not in _DEEPSEEK_FAMILY_ARCHS:
         return {}
@@ -2198,7 +2202,7 @@ def _deepseek_v4_kv_cache_dtype(view: Any) -> dict:
     """Slot pass in the DeepSeek V4 hook: default the kv-cache dtype to FP8
     (bfloat16 on NPU, where the pool geometry differs) and validate the
     result. The NPU split-backend writes stay in the hook."""
-    hf_config = view.get_model_config().hf_config
+    hf_config = model_config_of(view).hf_config
     model_arch = hf_config.architectures[0]
     if model_arch != "DeepseekV4ForCausalLM":
         return {}
@@ -2271,7 +2275,7 @@ def _flashinfer_allreduce_fusion_auto_enable(view: Any) -> dict:
     single-node systems. Reads the mid-resolution enable_dp_attention /
     moe_a2a_backend (after the DeepSeek CP and a2a declarations), exactly
     like the legacy tail block."""
-    model_arch = view.get_model_config().hf_config.architectures[0]
+    model_arch = model_config_of(view).hf_config.architectures[0]
     if envs.SGLANG_FLASHINFER_MNNVL_CUTEDSL_AR_FUSION.get() and model_arch in {
         "Qwen3_5MoeForCausalLM",
         "Qwen3_5MoeForConditionalGeneration",
@@ -2345,7 +2349,7 @@ def _deterministic_is_deepseek_model(view: Any) -> bool:
     if parse_connector_type(view.model_path) == ConnectorType.INSTANCE:
         return False
     try:
-        hf_config = view.get_model_config().hf_config
+        hf_config = model_config_of(view).hf_config
         return hf_config.architectures[0] in [
             "DeepseekV2ForCausalLM",
             "DeepseekV3ForCausalLM",
@@ -2413,8 +2417,8 @@ def _attention_backend_default(view: Any) -> dict:
     ):  # override the default attention backend
         return {"attention_backend": view.prefill_attention_backend}
     if view.attention_backend is None:
-        backend = view._get_default_attn_backend(
-            view.use_mla_backend(), view.get_model_config()
+        backend = get_default_attn_backend(
+            view, use_mla_backend(view), model_config_of(view)
         )
         logger.info(
             f"Attention backend not specified. Use {backend} backend by default."
@@ -2600,7 +2604,7 @@ def _fa4_page_constraint(view: Any) -> dict:
             or view.decode_attention_backend == "fa4"
             or view.prefill_attention_backend == "fa4"
         )
-        and not view.use_mla_backend()
+        and not use_mla_backend(view)
         and is_sm100_supported()
         # EAGLE topk>1 spec runs the two-pass page-tree cascade, which the FA4
         # CUTLASS kernel aborts on at page_size>1. That path only works at
@@ -2641,7 +2645,7 @@ def _attention_backend_platform_fallbacks(view: Any) -> dict:
 def _intel_xpu_page_constraint(view: Any) -> dict:
     _, decode_backend = attention_backends_of(view)
     if decode_backend == "intel_xpu":
-        if view.use_mla_backend():
+        if use_mla_backend(view):
             supported_page_sizes = [16, 32, 64, 128]
             msg = "Intel XPU attention backend for MLA Decode"
         else:
@@ -2658,7 +2662,7 @@ def _intel_xpu_page_constraint(view: Any) -> dict:
 @register_post_process
 def _attention_backend_dual_chunk(view: Any) -> dict:
     if (
-        getattr(view.get_model_config().hf_config, "dual_chunk_attention_config", None)
+        getattr(model_config_of(view).hf_config, "dual_chunk_attention_config", None)
         is not None
     ):
         if view.attention_backend is None:
@@ -3036,3 +3040,305 @@ def _hrm_text_attention_force(view: Any) -> dict:
             "attention."
         )
     return {"attention_backend": "triton"}
+
+
+def record_of(view: Any) -> Any:
+    """The record a view reads through.
+
+    For the few helpers a view cannot serve: `get_default_attn_backend` reads
+    through *both* overlays, so it needs the record the two views are built
+    from rather than either one of them.
+    """
+    return object.__getattribute__(view, "_server_args")
+
+
+def is_attention_backend_not_set(cfg: Any):
+    """None of the three attention backends has been decided yet.
+
+    Takes the view rather than the record: every read is a view read, and the
+    callers that hold a view (the override providers) would otherwise have to
+    reach back through it for a record.
+    """
+    return (
+        cfg.attention_backend is None
+        and cfg.prefill_attention_backend is None
+        and cfg.decode_attention_backend is None
+    )
+
+
+def get_default_attn_backend(server_args: Any, use_mla_backend: bool, model_config):
+    """
+    Auto select the fastest attention backend.
+
+    1. Models with MHA Architecture (e.g: Llama, QWen)
+        1.1 We will turn on FA3 on hopper unless user use spec decode with topk > 1 or page_size > 1.
+        1.2 Use trtllm_mha for SM100/SM103 (Blackwell B200/GB200/B300) excluding spec with topk > 1.
+           Note: trtllm_mha does not support SM120, which will fall back to flashinfer.
+        1.3 In other cases, we will use flashinfer if available, otherwise use triton.
+    2. Models with MLA Architecture and using FA3
+        2.1 We will use FA3 backend on hopper.
+        2.2 We will use Flashinfer backend on blackwell.
+        2.3 Otherwise, we will use triton backend.
+    """
+    cfg = resolving_view(server_args)
+    # OOT platforms provide their own default attention backend.
+    if current_platform.is_out_of_tree():
+        return current_platform.get_default_attention_backend()
+
+    # Whisper requires flashinfer for cross-attention CUDA graph support.
+    if "WhisperForConditionalGeneration" in (
+        model_config.hf_config.architectures or []
+    ):
+        return "flashinfer"
+
+    if not use_mla_backend:
+        # MHA architecture
+
+        if is_hopper_with_cuda_12_3() and is_no_spec_infer_or_topk_one(
+            resolved_view(server_args)
+        ):
+            # Note: flashinfer 0.6.1 caused performance regression on Hopper attention kernel
+            # Before the kernel is fixed, we choose fa3 as the default backend on Hopper MHA
+            # ref: https://github.com/sgl-project/sglang/issues/17411
+            return "fa3"
+        elif (
+            is_sm100_supported()
+            and is_no_spec_infer_or_topk_one(resolved_view(server_args))
+            and (
+                cfg.speculative_algorithm is None
+                or cfg.speculative_eagle_topk is not None
+            )
+        ):
+            # trtllm_mha requires equal K/V row widths; fa4 carries
+            # v_head_dim through.
+            if model_config.has_asymmetric_kv:
+                return "fa4"
+            return "trtllm_mha"
+        elif is_hip():
+            return "aiter"
+        elif is_mps():
+            return "torch_native"
+        else:
+            # FlashInfer does not support attention sinks.
+            if is_flashinfer_available() and not model_config.has_attention_sinks:
+                return "flashinfer"
+            return "triton"
+    else:
+        # MLA architecture
+        if is_hopper_with_cuda_12_3():
+            return "fa3"
+        elif is_sm100_supported():
+            return "flashinfer"
+        elif is_hip():
+            head_num = model_config.get_num_kv_heads(cfg.tp_size)
+            # TODO current aiter only support head number 16 or 128 head number
+            if head_num == 128 or head_num == 16:
+                return "aiter"
+            else:
+                return "triton"
+        elif is_mps():
+            return "torch_native"
+        else:
+            return "triton"
+
+
+def use_mla_backend(server_args: Any):
+    from sglang.srt.configs.model_config import AttentionArch
+
+    model_config = model_config_of(server_args)
+    return model_config.attention_arch == AttentionArch.MLA
+
+
+def should_report_expert_balancedness(server_args: Any) -> bool:
+    cfg = resolving_view(server_args)
+    return cfg.expert_balancedness_report_mode != "off"
+
+
+def model_config_of(server_args: Any):
+    """The model configuration this record describes, built once and memoised.
+
+    Takes a view as readily as the record: a view is a read overlay of one
+    record, the memo has to live on that record either way, and the callers
+    that hold a view would otherwise all have to unwrap it themselves.
+    """
+    if isinstance(server_args, (ResolvedView, ResolvingConfig)):
+        server_args = record_of(server_args)
+    # Lazy init to avoid circular import
+    cfg = resolving_view(server_args)
+    from sglang.srt.configs.model_config import ModelConfig
+
+    memo = getattr(server_args, "_model_config", None)
+    if memo is not None:
+        # The key is the path this record carried when the cache was
+        # filled. The GGUF and ModelScope handlers declare a different
+        # `model_path`, and a configuration built before them describes
+        # another checkpoint. `ModelConfig` re-points its own `model_path`
+        # at the local pull directory when the weights sit behind an
+        # object-store URI, so its field is not the key. A configuration a
+        # fixture supplied carries no key and is handed back as it is.
+        built_from = getattr(server_args, "_model_config_built_from", None)
+        if built_from is None or built_from == cfg.model_path:
+            return memo
+
+    model_config = ModelConfig.from_server_args(server_args)
+    server_args._model_config = model_config
+    server_args._model_config_built_from = cfg.model_path
+    if model_config.is_hybrid_swa:
+        logger.info(
+            "Hybrid SWA model detected. architectures=%s",
+            model_config.hf_config.architectures,
+        )
+    return model_config
+
+
+def post_capture_kv_sizing_planned(server_args: Any) -> bool:
+    """Whether the mem_fraction heuristic may skip the graph reserve; must be
+    False for any config the runtime won't post-capture-size, else it gets an
+    under-reserved fraction."""
+    cfg = resolving_view(server_args)
+    mla_enabled = use_mla_backend(server_args)
+    if not envs.SGLANG_ENABLE_POST_CAPTURE_KV_SIZING.get():
+        return False
+    if cfg.device != "cuda":
+        return False
+    if cfg.dcp_size != 1:
+        return False
+    if mla_enabled:
+        return False
+    if cfg.kv_cache_dtype == "fp4_e2m1":
+        return False
+    if cfg.prefill_only_disable_kv_cache:
+        return False
+    if cfg.enable_memory_saver:
+        return False
+    if envs.SGLANG_MOONCAKE_CUSTOM_MEM_POOL.get() is not None:
+        return False
+
+    if (
+        cfg.disaggregation_mode != "prefill"
+        and cfg.cuda_graph_config.decode.backend == Backend.DISABLED
+    ):
+        return False
+
+    if cfg.disaggregation_mode != "decode":
+        prefill_cfg = cfg.cuda_graph_config.prefill
+        # We can only skip eager activation headroom when the largest
+        # prefill forward batch size is already graph-captured. Otherwise,
+        # an eager forward will need more memory and lead to OOM.
+        if (
+            prefill_cfg.backend == Backend.DISABLED
+            or cfg.chunked_prefill_size <= 0
+            or max_prefill_buffer_tokens(server_args) > max(prefill_cfg.bs or (0,))
+        ):
+            return False
+
+    from sglang.srt.configs.model_config import is_deepseek_v4, is_minimax_sparse
+
+    hf_config = model_config_of(server_args).hf_config
+    if is_deepseek_v4(hf_config) or is_minimax_sparse(hf_config):
+        return False
+
+    return True
+
+
+def cutedsl_moe_max_num_tokens(server_args: Any) -> int:
+    """Largest number of tokens a single forward routes through a CuteDSL
+    MoE layer on one (DP) rank. Single source of truth for both the
+    standard-allgather wrapper buffers and the FlashInfer A2A dispatcher
+    budget. Max over the prefill (max_prefill_tokens), piecewise-prefill
+    capture, and decode/verify bounds; num_tokens_per_req is
+    speculative_num_draft_tokens under speculative decoding, else 1.
+    """
+    cfg = resolving_view(server_args)
+    if cfg.speculative_algorithm:
+        num_tokens_per_req = cfg.speculative_num_draft_tokens or 1
+    else:
+        num_tokens_per_req = 1
+    prefill_tokens = cfg.max_prefill_tokens
+    cg_config = cfg.cuda_graph_config
+    if cg_config is not None and cg_config.prefill.backend == Backend.TC_PIECEWISE:
+        prefill_tokens = max(prefill_tokens, cg_config.prefill.max_bs or 0)
+    decode_max_bs = (cg_config.decode.max_bs if cg_config is not None else 0) or 0
+    decode_tokens = decode_max_bs * num_tokens_per_req
+    return max(prefill_tokens, decode_tokens)
+
+
+def max_prefill_buffer_tokens(server_args: Any) -> int:
+    """Prefill-buffer ceiling: chunked_prefill_size, except PP dynamic
+    chunking can grow chunks toward max_prefill_tokens and probe at 1.25x."""
+    cfg = resolving_view(server_args)
+    chunked = (
+        cfg.chunked_prefill_size
+        if cfg.chunked_prefill_size and cfg.chunked_prefill_size > 0
+        else 0
+    )
+    tokens = chunked
+    if cfg.enable_dynamic_chunking and cfg.pp_size > 1 and chunked:
+        tokens = max(tokens, cfg.max_prefill_tokens or 0, math.ceil(chunked * 1.25))
+    return tokens
+
+
+def mamba_cache_chunk_size(server_args: Any) -> int:
+    # For mamba cache with extra buffer, the chunk size is the max of FLA_CHUNK_SIZE
+    # (or mamba_chunk_size if it is defined in the model's config) and page_size.
+    # It is used to determine the caching point in a sequence during prefill.
+    # A pre-seeded `_mamba_cache_chunk_size` (fixtures supply one so a dummy
+    # model never loads an HF config) is honored as-is; otherwise the memo
+    # is only kept once the record is resolved, because `page_size` below
+    # is resolution-written.
+    from sglang.srt.arg_groups.overrides import model_config_of
+
+    if not hasattr(server_args, "_mamba_cache_chunk_size"):
+
+        try:
+            from sglang.kernels.ops.attention.fla.chunk_delta_h import (
+                CHUNK_SIZE as FLA_CHUNK_SIZE,
+            )
+        except ImportError:
+            # Must match sglang.kernels.ops.attention.fla.chunk_delta_h.CHUNK_SIZE
+            FLA_CHUNK_SIZE = 64
+
+        hf_config = model_config_of(server_args).hf_config
+        chunk_size = getattr(hf_config, "mamba_chunk_size", FLA_CHUNK_SIZE)
+        page_size = resolved_view(server_args).page_size
+        assert (
+            max(chunk_size, page_size) % min(chunk_size, page_size) == 0
+        ), f"For SSM models, either chunk_size or page_size must be divisible by the other, got {chunk_size=}, {page_size=}"
+        if not getattr(server_args, "_resolution_finished", False):
+            return max(chunk_size, page_size)
+        server_args._mamba_cache_chunk_size = max(chunk_size, page_size)
+    return server_args._mamba_cache_chunk_size
+
+
+def max_speculative_num_draft_tokens(server_args: Any) -> Optional[int]:
+    """Return the maximum draft-token count speculative decoding may use.
+
+    Memoized only once the record is resolved: an answer computed off a raw
+    record describes inputs resolution is about to rewrite (auto speculative
+    sizing fills `speculative_num_draft_tokens` in), and a cache filled that
+    early would keep answering with it.
+    """
+    cfg = resolving_view(server_args)
+
+    memo = server_args.__dict__.get("_max_speculative_num_draft_tokens")
+    if memo is not None:
+        return memo
+    if cfg.speculative_num_draft_tokens is None:
+        result = None
+    elif not cfg.speculative_adaptive:
+        result = cfg.speculative_num_draft_tokens
+    else:
+        from sglang.srt.speculative.adaptive_spec_params import (
+            resolve_candidate_steps_from_config,
+        )
+
+        candidate_steps = resolve_candidate_steps_from_config(
+            cfg_path=cfg.speculative_adaptive_config,
+        )
+        # TODO: adaptive spec currently requires topk=1, so each runtime
+        # state needs steps + 1 draft-token slots. Revisit this if topk>1
+        # is supported.
+        result = max(candidate_steps) + 1
+    if getattr(server_args, "_resolution_finished", False):
+        server_args._max_speculative_num_draft_tokens = result
+    return result

python/sglang/srt/arg_groups/parallel_hook.py

@@ -11,6 +11,7 @@ from sglang.srt.arg_groups.overrides import (
     declare_resolution,
     resolved_view,
     resolving_view,
+    should_report_expert_balancedness,
 )
 from sglang.srt.connector import ConnectorType
 from sglang.srt.environ import envs
@@ -21,12 +22,14 @@ logger = logging.getLogger(__name__)
 
 
 def handle_context_parallelism(server_args: Any):
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     if parse_connector_type(cfg.model_path) != ConnectorType.INSTANCE:
         from sglang.srt.configs.model_config import is_deepseek_dsa
         from sglang.srt.layers.cp.utils import CP_V2_DEFAULT_MODEL_CLASSES
 
-        model_config = server_args.get_model_config()
+        model_config = model_config_of(server_args)
         hf_config = model_config.hf_config
         model_arch = hf_config.architectures[0]
         if model_arch in CP_V2_DEFAULT_MODEL_CLASSES:
@@ -154,6 +157,10 @@ def handle_dcp_validation(server_args: Any):
 def handle_data_parallelism(server_args: Any):
     # The dp_size==1 resets moved to the resolution pipeline
     # (arg_groups/overrides.py: _data_parallelism_defaults).
+    from sglang.srt.arg_groups.cuda_graph_hook import (
+        generate_prefill_cuda_graph_batch_sizes,
+    )
+
     cfg = resolving_view(server_args)
     from sglang.srt.arg_groups.overrides import (
         _data_parallelism_defaults,
@@ -213,8 +220,8 @@ def handle_data_parallelism(server_args: Any):
         ):
             clamped = {"max_bs": cfg.chunked_prefill_size}
             if (Phase.PREFILL, "bs") not in server_args._cuda_graph_config_locked:
-                clamped["bs"] = server_args._generate_prefill_cuda_graph_batch_sizes(
-                    clamped["max_bs"]
+                clamped["bs"] = generate_prefill_cuda_graph_batch_sizes(
+                    server_args, clamped["max_bs"]
                 )
             declare_resolution(
                 server_args,
@@ -636,7 +643,7 @@ def handle_expert_distribution_metrics(server_args: Any):
             "prometheus, both."
         )
 
-    if server_args.should_report_expert_balancedness() and (
+    if should_report_expert_balancedness(server_args) and (
         cfg.expert_distribution_recorder_mode is None
     ):
         declare_resolution(

python/sglang/srt/arg_groups/pd_disaggregation_hook.py

@@ -186,6 +186,7 @@ def _alias_bootstrap_port_to_api_port(server_args: ServerArgs) -> None:
 
 def handle_encoder_disaggregation(server_args: Any):
     from sglang.srt.arg_groups.model_hook import handle_language_model_only
+    from sglang.srt.arg_groups.overrides import model_config_of
     from sglang.srt.arg_groups.validation_hook import validate_ib_devices
     from sglang.srt.server_args import resolve_encoder_transfer_backend
 
@@ -223,7 +224,7 @@ def handle_encoder_disaggregation(server_args: Any):
         )
 
     # Validate model type for encoder disaggregation
-    hf_config = server_args.get_model_config().hf_config
+    hf_config = model_config_of(server_args).hf_config
     model_arch = hf_config.architectures[0]
     if cfg.encoder_transfer_backend == "auto":
         declare_resolution(

python/sglang/srt/arg_groups/serving_hook.py

@@ -751,6 +751,8 @@ def handle_multimodal_feature_transport(server_args: Any):
     may still auto-select CUDA VMM. The legacy CUDA IPC flag and environment
     variable remain supported so existing deployments map to this policy.
     """
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     requested_transport = cfg.mm_feature_transport
     legacy_ipc_is_set = envs.SGLANG_USE_CUDA_IPC_TRANSPORT.is_set()
@@ -785,7 +787,7 @@ def handle_multimodal_feature_transport(server_args: Any):
                 "--encoder-transfer-backend instead."
             )
         elif (
-            server_args.get_model_config().is_multimodal
+            model_config_of(server_args).is_multimodal
             and is_cuda()
             and cfg.disaggregation_mode == "null"
         ):
@@ -803,7 +805,7 @@ def handle_multimodal_feature_transport(server_args: Any):
                     supports_cuda_vmm_feature_transport,
                 )
 
-                if supports_cuda_vmm_feature_transport(server_args.get_model_config()):
+                if supports_cuda_vmm_feature_transport(model_config_of(server_args)):
                     requested_transport = "cuda_vmm"
                     logger.info(
                         "Multimodal feature transport auto-resolved to "

python/sglang/srt/arg_groups/speculative_hook.py

@@ -337,11 +337,12 @@ def _handle_dflash(server_args: ServerArgs) -> None:
 
 
 def _target_checkpoint_bundles_dspark_draft(server_args: ServerArgs) -> bool:
+    from sglang.srt.arg_groups.overrides import model_config_of
     from sglang.srt.speculative.dspark_components.dspark_config import (
         checkpoint_bundles_dspark_draft,
     )
 
-    return checkpoint_bundles_dspark_draft(server_args.get_model_config().hf_config)
+    return checkpoint_bundles_dspark_draft(model_config_of(server_args).hf_config)
 
 
 def _handle_dspark(server_args: ServerArgs) -> None:
@@ -662,6 +663,8 @@ def _handle_frozen_kv_mtp(server_args: ServerArgs) -> None:
 
 
 def _handle_eagle_family(server_args: ServerArgs) -> None:
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     cfg = resolving_view(server_args)
     from sglang.srt.arg_groups.overrides import (
         attention_backends_of,
@@ -706,7 +709,7 @@ def _handle_eagle_family(server_args: ServerArgs) -> None:
             "eagle speculative decoding."
         )
 
-    model_arch = server_args.get_model_config().hf_config.architectures[0]
+    model_arch = model_config_of(server_args).hf_config.architectures[0]
     if model_arch in [
         "DeepseekV32ForCausalLM",
         "DeepseekV3ForCausalLM",

python/sglang/srt/arg_groups/validation_hook.py

@@ -9,6 +9,7 @@ import os
 from typing import Any, Dict, List, Optional
 
 from sglang.srt.arg_groups.overrides import (
+    resolved_view,
     resolving_view,
 )
 from sglang.srt.distributed.device_communicators.mooncake_transfer_engine import (
@@ -389,7 +390,7 @@ def validate_ib_devices(server_args: Any, device_str: Optional[str]) -> Optional
 
 
 def validate_experimental_sgl_marlin(server_args: Any):
-    view = server_args._resolved()
+    view = resolved_view(server_args)
     if view.moe_runner_backend != "experimental_sgl_marlin":
         return
 

python/sglang/srt/entrypoints/engine.py

@@ -48,7 +48,10 @@ import torch
 import uvloop
 import zmq
 
-from sglang.srt.arg_groups.overrides import resolving_view
+from sglang.srt.arg_groups.overrides import (
+    resolved_view,
+    resolving_view,
+)
 from sglang.srt.elastic_ep.expert_backup_manager import run_expert_backup_manager
 from sglang.srt.entrypoints.engine_info_bootstrap_server import (
     EngineInfoBootstrapServer,
@@ -1627,6 +1630,8 @@ class Engine(EngineScoreMixin, EngineBase):
 
 
 def _set_envs_and_config(server_args: ServerArgs):
+    from sglang.srt.arg_groups.overrides import attention_backends_of
+
     cfg = resolving_view(server_args)
     # Set global environments
     # MNNVL fabric (GB200/GB300) multi-node: cross-node NVLink needs NCCL's
@@ -1678,7 +1683,7 @@ def _set_envs_and_config(server_args: ServerArgs):
 
     # Check flashinfer version
     if not get_bool_env_var("SGLANG_SKIP_SGL_KERNEL_VERSION_CHECK"):
-        if "flashinfer" in cfg.get_attention_backends():
+        if "flashinfer" in attention_backends_of(resolved_view(cfg)):
             assert_pkg_version(
                 "flashinfer_python",
                 "0.6.17",

python/sglang/srt/eplb/expert_distribution.py

@@ -38,6 +38,7 @@ import einops
 import torch
 import torch.distributed
 
+from sglang.srt.arg_groups.overrides import should_report_expert_balancedness
 from sglang.srt.environ import envs
 from sglang.srt.model_executor.forward_batch_info import ForwardBatch
 from sglang.srt.observability.metrics_collector import (
@@ -179,7 +180,7 @@ class _ExpertDistributionRecorderReal(ExpertDistributionRecorder):
             for k in self._accumulator.get_single_pass_gatherer_keys()
         }
 
-        if server_args.should_report_expert_balancedness():
+        if should_report_expert_balancedness(server_args):
             logger.info(
                 "ExpertDistributionRecorder auto start record since "
                 f"expert_balancedness_report_mode={get_exec().moe.expert_balancedness_report_mode}"
@@ -718,7 +719,7 @@ class _UtilizationRateAccumulatorMixin(_Accumulator):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
-        self._enable = self._server_args.should_report_expert_balancedness()
+        self._enable = should_report_expert_balancedness(self._server_args)
 
         if self._enable:
             self.window_sizes = EPLB_BALANCEDNESS_WINDOW_SIZES

python/sglang/srt/hardware_backend/npu/utils.py

@@ -44,7 +44,7 @@ def set_default_server_args(args: "ServerArgs"):
     """
     Set default server arguments for NPU backend.
     """
-    from sglang.srt.arg_groups.overrides import resolving_view
+    from sglang.srt.arg_groups.overrides import resolving_view, use_mla_backend
 
     cfg = resolving_view(args)
 
@@ -148,7 +148,7 @@ def set_default_server_args(args: "ServerArgs"):
             "set_default_server_args",
             hicache_io_backend="kernel_ascend",
         )
-        if args.use_mla_backend():
+        if use_mla_backend(args):
             declare_resolution(
                 args,
                 "set_default_server_args",

python/sglang/srt/layers/attention/attention_registry.py

@@ -74,7 +74,12 @@ def create_trtllm_mla_backend(runner):
     if not runner.use_mla_backend:
         raise ValueError("trtllm_mla backend can only be used with MLA models.")
     if get_parallel().dcp_enabled and get_spec().speculative_algorithm is not None:
-        _, decode_backend = runner.server_args.get_attention_backends()
+        from sglang.srt.arg_groups.overrides import (
+            attention_backends_of,
+            resolved_view,
+        )
+
+        _, decode_backend = attention_backends_of(resolved_view(runner.server_args))
         if decode_backend == "trtllm_mla":
             raise ValueError(
                 "trtllm_mla cannot serve decode context parallelism with speculative "

python/sglang/srt/layers/attention/tokenspeed_mla_backend.py

@@ -56,7 +56,7 @@ from sglang.srt.layers.attention.trtllm_mla_backend import (
 )
 from sglang.srt.layers.dcp.layout import get_dcp_lens
 from sglang.srt.layers.logits_processor import get_in_autotune_dummy_run
-from sglang.srt.runtime_context import get_parallel
+from sglang.srt.runtime_context import get_parallel, max_speculative_num_draft_tokens
 from sglang.srt.utils import is_flashinfer_available, is_tokenspeed_mla_available
 
 if is_flashinfer_available():
@@ -145,9 +145,7 @@ class TokenspeedMLABackend(TRTLLMMLABackend):
                 self.device,
                 self.num_q_heads,
                 self.kv_lora_rank,
-                max_q_len=(
-                    model_runner.server_args.max_speculative_num_draft_tokens or 1
-                ),
+                max_q_len=(max_speculative_num_draft_tokens() or 1),
             )
 
             # Pre-JIT the prefill kernel variants. Each cute.compile takes 1-2

python/sglang/srt/layers/cp/bcg.py

@@ -21,6 +21,7 @@ from typing import TYPE_CHECKING, Any, Dict, Optional
 
 import torch
 
+from sglang.srt.arg_groups.overrides import resolved_view
 from sglang.srt.layers.cp.base import get_cp_strategy
 from sglang.srt.layers.cp.padding import get_cp_padding_align_size
 from sglang.srt.layers.cp.utils import (
@@ -42,11 +43,11 @@ if TYPE_CHECKING:
 
 def supports_prefill_cp_bcg(server_args: ServerArgs) -> bool:
     """Return whether the selected prefill-CP configuration supports BCG."""
-    from sglang.srt.arg_groups.overrides import resolving_view
+    from sglang.srt.arg_groups.overrides import attention_backends_of, resolving_view
 
     cfg = resolving_view(server_args)
-    resolved = server_args._resolved()
-    prefill_attention_backend, _ = server_args._resolved_attention_backends()
+    resolved = resolved_view(server_args)
+    prefill_attention_backend, _ = attention_backends_of(resolved_view(server_args))
     return (
         cfg.enable_prefill_cp
         and resolved.attn_cp_size == cfg.tp_size
@@ -64,7 +65,7 @@ def filter_prefill_cp_bcg_capture_num_tokens(
     capture_num_tokens: list[int], server_args: ServerArgs
 ) -> list[int]:
     """Keep only token buckets where the zigzag CP strategy can run."""
-    min_num_tokens = server_args._resolved().attn_cp_size * 2
+    min_num_tokens = resolved_view(server_args).attn_cp_size * 2
     filtered = [size for size in capture_num_tokens if size >= min_num_tokens]
     if not filtered:
         raise ValueError(

python/sglang/srt/layers/moe/kt_ep_wrapper.py

@@ -76,8 +76,10 @@ def create_kt_config_from_server_args(
     if server_args.kt_weight_path is None:
         return None
 
+    from sglang.srt.arg_groups.overrides import model_config_of
+
     num_layers = getattr(
-        server_args.get_model_config().hf_config, "num_hidden_layers", None
+        model_config_of(server_args).hf_config, "num_hidden_layers", None
     )
 
     return KTConfig(

python/sglang/srt/layers/moe/qwen35_flashinfer_fusion.py

@@ -8,7 +8,7 @@ from typing import Optional
 
 import torch
 
-from sglang.srt.arg_groups.overrides import resolving_view
+from sglang.srt.arg_groups.overrides import cutedsl_moe_max_num_tokens, resolving_view
 from sglang.srt.layers.communicator import (
     CommunicateWithAllReduceAndLayerNormFn,
     LayerCommunicator,
@@ -37,7 +37,7 @@ def resolve_max_m(model_runner) -> int:
     decode_config = server_args.cuda_graph_config.decode
     prefill_config = server_args.cuda_graph_config.prefill
     candidates = [
-        server_args.cutedsl_moe_max_num_tokens(),
+        cutedsl_moe_max_num_tokens(model_runner.server_args),
         model_runner.max_running_requests,
         decode_config.max_bs,
         prefill_config.max_bs,

python/sglang/srt/model_executor/model_runner_components/kv_pool_runtime.py

@@ -29,8 +29,10 @@ logger = logging.getLogger(__name__)
 def is_post_capture_kv_active(
     *, server_args: ServerArgs, is_draft_worker: bool
 ) -> bool:
+    from sglang.srt.arg_groups.overrides import post_capture_kv_sizing_planned
+
     return (
-        server_args.post_capture_kv_sizing_planned()
+        post_capture_kv_sizing_planned(server_args)
         and current_platform.is_cuda()
         and not is_draft_worker
     )

python/sglang/srt/model_executor/pool_configurator.py

@@ -44,6 +44,7 @@ from sglang.srt.runtime_context import (
     get_parallel,
     get_schedule,
     get_spec,
+    max_speculative_num_draft_tokens,
 )
 from sglang.srt.utils.common import (
     ceil_align,
@@ -780,9 +781,7 @@ class DSV4PoolConfigurator(MemoryPoolConfigurator):
         self.swa_page_size = cfg.window_size
         self.swa_ratio = get_schedule().swa_full_tokens_ratio
         self.is_speculative = get_spec().speculative_algorithm is not None
-        self.online_c128_mtp_max_draft_tokens = (
-            kvc.server_args.max_speculative_num_draft_tokens or 0
-        )
+        self.online_c128_mtp_max_draft_tokens = max_speculative_num_draft_tokens() or 0
         self.requested_max_running_requests_per_worker = (
             get_schedule().max_running_requests // kvc.ps.attn_dp_size
             if get_schedule().max_running_requests is not None
@@ -814,7 +813,7 @@ class DSV4PoolConfigurator(MemoryPoolConfigurator):
         if self.is_speculative:
             # Ring is sized once here, so it must serve the largest adaptive tier.
             self._assert_ring_serves_draft_tokens(
-                kvc.server_args.max_speculative_num_draft_tokens or 0
+                max_speculative_num_draft_tokens() or 0
             )
 
         self.bytes_per_full_token = self._get_bytes_per_full_token()

python/sglang/srt/model_executor/runner/flashinfer_autotune.py

@@ -30,7 +30,9 @@ from sglang.srt.runtime_context import (
     get_disagg,
     get_exec,
     get_model,
+    get_schedule,
     get_spec,
+    max_prefill_buffer_tokens,
 )
 from sglang.srt.utils import empty_context, log_info_on_rank0
 
@@ -342,9 +344,7 @@ def maybe_flashinfer_autotune_extend(
     mr = runner.model_runner
     # Prefer the per-rank scheduler buffer while preserving the legacy ceiling
     # when chunked prefill is disabled.
-    num_tokens = (
-        mr.server_args.max_prefill_buffer_tokens() or mr.server_args.max_prefill_tokens
-    )
+    num_tokens = max_prefill_buffer_tokens() or get_schedule().max_prefill_tokens
     if num_tokens <= (decode_num_tokens or 0):
         return  # decode-shaped autotune already covered these buckets
     is_pd_prefill_target = (

python/sglang/srt/model_loader/expert_pack_runtime.py

@@ -15,6 +15,8 @@ import sys
 from pathlib import Path
 from typing import Any
 
+from sglang.srt.arg_groups.overrides import declare_resolution
+
 METADATA_FORMAT_VERSION = 3
 GGUF_SHARD_SUFFIX_RE = re.compile(r"-\d{5}-of-\d{5}\.gguf$")
 DEEPSEEK_METADATA_FORMAT_VERSION = 4
@@ -215,7 +217,8 @@ def prepare_raw_kimi_server_args(
         model_path,
         tokenizer_dir=tokenizer_path,
     )
-    server_args._declare(
+    declare_resolution(
+        server_args,
         "prepare_raw_kimi_server_args",
         model_path=str(assets["model_dir"]),
         tokenizer_path=str(assets["model_dir"]),
@@ -538,7 +541,8 @@ def prepare_raw_deepseek_server_args(
     config_sha256 = _deepseek_digest(
         model_value.get("config_sha256"), "model.config_sha256"
     )
-    server_args._declare(
+    declare_resolution(
+        server_args,
         "prepare_raw_deepseek_server_args",
         model_path=str(model_config.parent),
         tokenizer_path=str(model_config.parent),

python/sglang/srt/runtime_context.py

@@ -1672,7 +1672,7 @@ def max_prefill_buffer_tokens() -> int:
 
     Every input is a published leaf (``schedule`` plus the configured PP size),
     so this derives from the bags and follows a post-publish override;
-    ``ServerArgs.max_prefill_buffer_tokens`` is the pre-publish equivalent and
+    ``overrides.max_prefill_buffer_tokens`` is the pre-publish equivalent and
     ``TestDerivedPredicatesAgreeAcrossTiers`` pins the two equal.
     """
     import math
@@ -1726,17 +1726,19 @@ def pre_capture_activation_reserve_mb(gpu_mem: float | None) -> float:
 # --- Derived config accessors ------------------------------------------------
 #
 # A few values are computed from several config fields plus the HF config, so
-# they are ``ServerArgs`` members rather than namespace leaves. Business code
-# must not reach for the startup record to get them: these accessors are the
-# named home, and this module — which owns the slot — is the only place that
-# reads it. Each one keeps the member's exact semantics, including which model
+# they are derived accessors rather than namespace leaves. Business code must
+# not reach for the startup record to get them: these accessors are the named
+# home, and this module — which owns the slot — is the only place that reads
+# it. Each one keeps the pre-publish function's exact semantics, including which model
 # config it derives from (always the process's, i.e. the target's).
 
 
 def mamba_cache_chunk_size() -> int:
     """The caching point granularity for mamba state: ``max(the model's mamba
     chunk size, page_size)``. Cached on the config after the first call."""
-    return get_server_args().mamba_cache_chunk_size
+    from sglang.srt.arg_groups.overrides import mamba_cache_chunk_size as _of
+
+    return _of(get_server_args())
 
 
 def mamba_checkpoint_grid(tree_page: int) -> int:
@@ -1759,7 +1761,7 @@ def max_speculative_num_draft_tokens() -> int | None:
     """The largest draft-token count speculative decoding may use.
 
     All three inputs are ``spec`` leaves, so this derives from the bags and
-    follows a post-publish override; ``ServerArgs.max_speculative_num_draft_tokens``
+    follows a post-publish override; ``overrides.max_speculative_num_draft_tokens``
     is the pre-publish equivalent. Adaptive spec resolves the count from its
     candidate-step table instead of the flat field.
     """
@@ -1788,7 +1790,9 @@ def _adaptive_draft_token_bound(cfg_path: str | None) -> int:
 
 def uses_mla_backend() -> bool:
     """Whether this process's model runs the MLA attention path."""
-    return get_server_args().use_mla_backend()
+    from sglang.srt.arg_groups.overrides import use_mla_backend
+
+    return use_mla_backend(get_server_args())
 
 
 def attention_backends() -> tuple:
@@ -1796,7 +1800,7 @@ def attention_backends() -> tuple:
     back to ``attention_backend``.
 
     All three inputs are ``exec.kernel`` leaves, so this derives from the bags
-    and follows a post-publish override; ``ServerArgs.get_attention_backends``
+    and follows a post-publish override; ``overrides.attention_backends_of``
     is the pre-publish equivalent the resolution pipeline uses. A built runner
     stamps its own resolved pair (``ModelRunner.prefill_attention_backend_str``);
     read that when there is a runner in hand.
@@ -1810,7 +1814,9 @@ def attention_backends() -> tuple:
 
 def process_model_config():
     """The process's ``ModelConfig`` (built once from the published config)."""
-    return get_server_args().get_model_config()
+    from sglang.srt.arg_groups.overrides import model_config_of
+
+    return model_config_of(get_server_args())
 
 
 def cutedsl_moe_max_num_tokens() -> int:
@@ -1818,7 +1824,7 @@ def cutedsl_moe_max_num_tokens() -> int:
 
     Every input is a published leaf (``spec``, ``schedule``, ``exec.graph``), so
     this derives from the bags and follows a post-publish override;
-    ``ServerArgs.cutedsl_moe_max_num_tokens`` is the pre-publish equivalent the
+    ``overrides.cutedsl_moe_max_num_tokens`` is the pre-publish equivalent the
     resolution pipeline uses. Max over the prefill bound, the piecewise-prefill
     capture, and the decode/verify bound.
     """

python/sglang/srt/server_args.py

@@ -37,11 +37,8 @@ import argparse
 import copy
 import dataclasses
 import functools
-import glob
 import json
 import logging
-import math
-import os
 import tempfile
 import uuid
 from typing import Any, Callable, Dict, List, Literal, Optional, Union
@@ -56,11 +53,9 @@ from sglang.srt.arg_groups.argparse_actions import (
     LoRAPathAction,
 )
 from sglang.srt.arg_groups.overrides import (
-    attention_backends_of,
     mamba_extra_buffer_lazy_of,
     mamba_extra_buffer_of,
     remote_instance_transfer_engine_of,
-    resolved_view,
     resolving_view,
 )
 from sglang.srt.environ import envs
@@ -69,23 +64,14 @@ from sglang.srt.lora.lora_registry import LoRARef
 from sglang.srt.model_executor.cuda_graph_config import (
     Backend,
     CudaGraphConfig,
-    Phase,
     parse_cuda_graph_config_arg,
-    with_phase,
 )
 from sglang.srt.parser.reasoning_parser import ReasoningParser
-from sglang.srt.platforms import current_platform
 from sglang.srt.speculative.decoupled_spec_io import DecoupledSpecIpcConfig
 from sglang.srt.utils.common import (
     LORA_TARGET_ALL_MODULES,
     SUPPORTED_LORA_TARGET_MODULES,
     human_readable_int,
-    is_flashinfer_available,
-    is_hip,
-    is_hopper_with_cuda_12_3,
-    is_mps,
-    is_no_spec_infer_or_topk_one,
-    is_sm100_supported,
     json_list_type,
     nullable_str,
 )
@@ -3745,7 +3731,7 @@ class ServerArgs:
 
         # Everything outside the fields, enumerated from the instance: the raw
         # snapshot, the stash, and what resolution memoized -- including the
-        # `get_model_config()` memo, which the copy carries over rather than
+        # model-configuration memo, which the copy carries over rather than
         # rebuild.
         field_names = {field.name for field in dataclasses.fields(self)}
         for name, value in vars(self).items():
@@ -3763,91 +3749,10 @@ class ServerArgs:
         object.__setattr__(replacement, "_resolution_finished", True)
         return replacement
 
-    def _declare(self, source: str, **fields: Any) -> None:
-        """This record's handlers declaring their resolution writes.
-
-        See ``arg_groups.overrides.declare_resolution``, which the hooks these
-        handlers call reach directly.
-        """
-        from sglang.srt.arg_groups.overrides import declare_resolution
-
-        declare_resolution(self, source, **fields)
-
     # ------------------------------------------------------------------
     # CUDA graph configuration resolution
     # ------------------------------------------------------------------
 
-    def _apply_cuda_graph_disaggregation_roles(self):
-        cfg = resolving_view(self)
-        if cfg.disaggregation_mode == "prefill":
-            if (Phase.DECODE, "backend") not in self._cuda_graph_config_locked:
-                self._declare(
-                    "_apply_cuda_graph_disaggregation_roles",
-                    cuda_graph_config=with_phase(
-                        cfg.cuda_graph_config, Phase.DECODE, backend=Backend.DISABLED
-                    ),
-                )
-        elif cfg.disaggregation_mode == "decode":
-            if (Phase.PREFILL, "backend") not in self._cuda_graph_config_locked:
-                self._declare(
-                    "_apply_cuda_graph_disaggregation_roles",
-                    cuda_graph_config=with_phase(
-                        cfg.cuda_graph_config, Phase.PREFILL, backend=Backend.DISABLED
-                    ),
-                )
-
-    def post_capture_kv_sizing_planned(self) -> bool:
-        """Whether the mem_fraction heuristic may skip the graph reserve; must be
-        False for any config the runtime won't post-capture-size, else it gets an
-        under-reserved fraction."""
-        cfg = resolving_view(self)
-        # use_mla_backend is a method at args time but ModelRunner overwrites it
-        # with a bool on global_server_args (see the FIXME there) -- handle both.
-        use_mla = self.use_mla_backend
-        mla_enabled = use_mla() if callable(use_mla) else use_mla
-        if not envs.SGLANG_ENABLE_POST_CAPTURE_KV_SIZING.get():
-            return False
-        if cfg.device != "cuda":
-            return False
-        if cfg.dcp_size != 1:
-            return False
-        if mla_enabled:
-            return False
-        if cfg.kv_cache_dtype == "fp4_e2m1":
-            return False
-        if cfg.prefill_only_disable_kv_cache:
-            return False
-        if cfg.enable_memory_saver:
-            return False
-        if envs.SGLANG_MOONCAKE_CUSTOM_MEM_POOL.get() is not None:
-            return False
-
-        if (
-            cfg.disaggregation_mode != "prefill"
-            and cfg.cuda_graph_config.decode.backend == Backend.DISABLED
-        ):
-            return False
-
-        if cfg.disaggregation_mode != "decode":
-            prefill_cfg = cfg.cuda_graph_config.prefill
-            # We can only skip eager activation headroom when the largest
-            # prefill forward batch size is already graph-captured. Otherwise,
-            # an eager forward will need more memory and lead to OOM.
-            if (
-                prefill_cfg.backend == Backend.DISABLED
-                or cfg.chunked_prefill_size <= 0
-                or self.max_prefill_buffer_tokens() > max(prefill_cfg.bs or (0,))
-            ):
-                return False
-
-        from sglang.srt.configs.model_config import is_deepseek_v4, is_minimax_sparse
-
-        hf_config = self.get_model_config().hf_config
-        if is_deepseek_v4(hf_config) or is_minimax_sparse(hf_config):
-            return False
-
-        return True
-
     def pre_capture_activation_reserve_mb(self, gpu_mem: Optional[float]) -> float:
         # Runtime activation working-set reserve for eager decode above the captured
         # max_bs and transient prefill/logits; also covers fixed state caches.
@@ -3870,347 +3775,13 @@ class ServerArgs:
             reserved_mem = max(reserved_mem, 10 * 1024)
         return reserved_mem
 
-    def reserve_for_graph_mb(self) -> float:
-        cfg = resolving_view(self)
-        decode_cuda_graph_config = cfg.cuda_graph_config.decode
-        prefill_cuda_graph_config = cfg.cuda_graph_config.prefill
-
-        reserved_mem = 0.0
-        if (
-            cfg.disaggregation_mode != "prefill"
-            and decode_cuda_graph_config.backend != Backend.DISABLED
-        ):
-            reserved_mem += decode_cuda_graph_config.max_bs * 2
-
-        if (
-            self._resolved().enable_dp_attention
-            and cfg.disaggregation_mode != "prefill"
-        ):
-            # DP attention needs more padding for some operations, and much more for large
-            # cuda graph max bs (torch allocator / implementation inefficiencies).
-            reserved_mem += decode_cuda_graph_config.max_bs * cfg.dp_size * 3
-            if decode_cuda_graph_config.max_bs > 300:
-                reserved_mem += decode_cuda_graph_config.max_bs * cfg.dp_size * 1.5
-
-        if (
-            cfg.disaggregation_mode != "decode"
-            and prefill_cuda_graph_config.backend != Backend.DISABLED
-        ):
-            if not self.use_mla_backend():
-                # Only non-torch memory is counted; torch memory is reused by cuda graph capture.
-                reserved_mem += len(prefill_cuda_graph_config.bs) * 8
-            else:
-                # MLA backend overhead is much higher than expected with fa3.
-                reserved_mem += 1.5 * 1024
-
-            if (
-                prefill_cuda_graph_config.backend == Backend.BREAKABLE
-                and resolved_view(self).moe_a2a_backend == "deepep"
-            ):
-                # Prefill-BCG DeepEP delta (bridge pool + NVL first-touch
-                # during capture); decode-side DeepEP is a baseline cost.
-                reserved_mem += 1 * 1024
-
-        return reserved_mem
-
-    def reserve_for_deepep_a2a_mb(self) -> float:
-        # DeepEP all-to-all buffers captured in the decode graph are real extra
-        # allocations, reserved on top of the floor.
-
-        cfg = resolving_view(self)
-        decode_cuda_graph_config = cfg.cuda_graph_config.decode
-        if (
-            cfg.disaggregation_mode != "prefill"
-            and decode_cuda_graph_config.backend != Backend.DISABLED
-            and resolved_view(self).moe_a2a_backend == "deepep"
-        ):
-            return 2 * 1024
-        return 0.0
-
-    def _generate_decode_cuda_graph_batch_sizes(self, max_bs: int):
-        """
-        Generate the list of batch sizes for CUDA graph capture based on max_bs.
-        This integrates the logic from cuda_graph_runner.py.
-        """
-        cfg = resolving_view(self)
-        # Handle disable_cuda_graph_padding as the first condition for both spec and non-spec
-        if cfg.disable_cuda_graph_padding:
-            capture_bs = list(range(1, max_bs + 1))
-        elif cfg.speculative_algorithm is None:
-            # Normal case:
-            capture_bs = (
-                [1, 2, 4, 8, 12]
-                + list(range(16, 257, 8))
-                + list(range(272, 512, 16))
-                + list(range(512, max_bs + 1, 32))
-            )
-        else:
-            # Spec decoding case: less padding for smaller batch sizes
-            capture_bs = (
-                list(range(1, 9, 1))
-                + list(range(10, 33, 2))
-                + list(range(40, 65, 4))
-                + list(range(72, 257, 8))
-                + list(range(272, max_bs + 1, 16))
-            )
-
-        capture_bs = [bs for bs in capture_bs if bs <= max_bs]
-
-        if max_bs not in capture_bs:
-            capture_bs.append(max_bs)
-
-        return capture_bs
-
-    def _generate_cpu_graph_batch_sizes(self):
-        """
-        Generate the list of batch sizes for CPU graph capture based on torch_compile_max_bs.
-        """
-        cfg = resolving_view(self)
-        if cfg.disable_cuda_graph_padding:
-            capture_bs = list(range(1, cfg.torch_compile_max_bs + 1))
-        else:
-            capture_bs = sorted(
-                set().union(
-                    range(1, 17),
-                    range(18, 31, 2),
-                    range(32, 81, 4),
-                    range(84, cfg.torch_compile_max_bs + 1, 8),
-                    {cfg.torch_compile_max_bs},
-                )
-            )
-        capture_bs = [bs for bs in capture_bs if bs <= cfg.torch_compile_max_bs]
-
-        return capture_bs
-
-    def _generate_prefill_cuda_graph_batch_sizes(self, max_bs: int):
-        """
-        Generate the list of batch sizes for prefill CUDA graph capture
-        based on max_bs. For tc_piecewise prefill, bs carries the
-        captured token count (one shape knob per phase).
-        """
-        capture_sizes = (
-            list(range(4, 33, 4))
-            + list(range(48, 257, 16))
-            + list(range(288, 513, 32))
-            + list(range(576, 1024 + 1, 64))
-            + list(range(1280, 4096 + 1, 256))
-            + list(range(4608, max_bs + 1, 512))
-        )
-
-        capture_sizes = [s for s in capture_sizes if s <= max_bs]
-
-        return capture_sizes
-
-    def _set_default_dsa_kv_cache_dtype(self, major: int, quantization: str) -> None:
-        # Moved to the resolution pipeline (arg_groups/overrides.py:
-        # _dsa_kv_cache_dtype_default), invoked here at its legacy slot.
-        from sglang.srt.arg_groups.overrides import (
-            _dsa_kv_cache_dtype_default,
-            run_post_process_pass,
-        )
-
-        run_post_process_pass(self, _dsa_kv_cache_dtype_default)
-
-    def _set_default_dsa_backends(self, major: int) -> None:
-        # Moved to the resolution pipeline (arg_groups/overrides.py:
-        # _dsa_split_backend_resolution), invoked here at its legacy slot.
-        from sglang.srt.arg_groups.overrides import (
-            _dsa_split_backend_resolution,
-            run_post_process_pass,
-        )
-
-        run_post_process_pass(self, _dsa_split_backend_resolution)
-
     def _support_mamba_cache_extra_buffer(self, model_arch: str):
         from sglang.srt.arg_groups.overrides import supports_mamba_cache_extra_buffer
 
         return supports_mamba_cache_extra_buffer(self, model_arch)
 
-    def _get_default_attn_backend(self, use_mla_backend: bool, model_config):
-        """
-        Auto select the fastest attention backend.
-
-        1. Models with MHA Architecture (e.g: Llama, QWen)
-            1.1 We will turn on FA3 on hopper unless user use spec decode with topk > 1 or page_size > 1.
-            1.2 Use trtllm_mha for SM100/SM103 (Blackwell B200/GB200/B300) excluding spec with topk > 1.
-               Note: trtllm_mha does not support SM120, which will fall back to flashinfer.
-            1.3 In other cases, we will use flashinfer if available, otherwise use triton.
-        2. Models with MLA Architecture and using FA3
-            2.1 We will use FA3 backend on hopper.
-            2.2 We will use Flashinfer backend on blackwell.
-            2.3 Otherwise, we will use triton backend.
-        """
-        cfg = resolving_view(self)
-        # OOT platforms provide their own default attention backend.
-        if current_platform.is_out_of_tree():
-            return current_platform.get_default_attention_backend()
-
-        # Whisper requires flashinfer for cross-attention CUDA graph support.
-        if "WhisperForConditionalGeneration" in (
-            model_config.hf_config.architectures or []
-        ):
-            return "flashinfer"
-
-        if not use_mla_backend:
-            # MHA architecture
-
-            if is_hopper_with_cuda_12_3() and is_no_spec_infer_or_topk_one(
-                resolved_view(self)
-            ):
-                # Note: flashinfer 0.6.1 caused performance regression on Hopper attention kernel
-                # Before the kernel is fixed, we choose fa3 as the default backend on Hopper MHA
-                # ref: https://github.com/sgl-project/sglang/issues/17411
-                return "fa3"
-            elif (
-                is_sm100_supported()
-                and is_no_spec_infer_or_topk_one(resolved_view(self))
-                and (
-                    cfg.speculative_algorithm is None
-                    or cfg.speculative_eagle_topk is not None
-                )
-            ):
-                # trtllm_mha requires equal K/V row widths; fa4 carries
-                # v_head_dim through.
-                if model_config.has_asymmetric_kv:
-                    return "fa4"
-                return "trtllm_mha"
-            elif is_hip():
-                return "aiter"
-            elif is_mps():
-                return "torch_native"
-            else:
-                # FlashInfer does not support attention sinks.
-                if is_flashinfer_available() and not model_config.has_attention_sinks:
-                    return "flashinfer"
-                return "triton"
-        else:
-            # MLA architecture
-            if is_hopper_with_cuda_12_3():
-                return "fa3"
-            elif is_sm100_supported():
-                return "flashinfer"
-            elif is_hip():
-                head_num = model_config.get_num_kv_heads(self.tp_size)
-                # TODO current aiter only support head number 16 or 128 head number
-                if head_num == 128 or head_num == 16:
-                    return "aiter"
-                else:
-                    return "triton"
-            elif is_mps():
-                return "torch_native"
-            else:
-                return "triton"
-
-    def cutedsl_moe_max_num_tokens(self) -> int:
-        """Largest number of tokens a single forward routes through a CuteDSL
-        MoE layer on one (DP) rank. Single source of truth for both the
-        standard-allgather wrapper buffers and the FlashInfer A2A dispatcher
-        budget. Max over the prefill (max_prefill_tokens), piecewise-prefill
-        capture, and decode/verify bounds; num_tokens_per_req is
-        speculative_num_draft_tokens under speculative decoding, else 1.
-        """
-        cfg = resolving_view(self)
-        if cfg.speculative_algorithm:
-            num_tokens_per_req = cfg.speculative_num_draft_tokens or 1
-        else:
-            num_tokens_per_req = 1
-        prefill_tokens = cfg.max_prefill_tokens
-        cg_config = cfg.cuda_graph_config
-        if cg_config is not None and cg_config.prefill.backend == Backend.TC_PIECEWISE:
-            prefill_tokens = max(prefill_tokens, cg_config.prefill.max_bs or 0)
-        decode_max_bs = (cg_config.decode.max_bs if cg_config is not None else 0) or 0
-        decode_tokens = decode_max_bs * num_tokens_per_req
-        return max(prefill_tokens, decode_tokens)
-
-    def max_prefill_buffer_tokens(self) -> int:
-        """Prefill-buffer ceiling: chunked_prefill_size, except PP dynamic
-        chunking can grow chunks toward max_prefill_tokens and probe at 1.25x."""
-        cfg = resolving_view(self)
-        chunked = (
-            cfg.chunked_prefill_size
-            if cfg.chunked_prefill_size and cfg.chunked_prefill_size > 0
-            else 0
-        )
-        tokens = chunked
-        if cfg.enable_dynamic_chunking and cfg.pp_size > 1 and chunked:
-            tokens = max(tokens, cfg.max_prefill_tokens or 0, math.ceil(chunked * 1.25))
-        return tokens
-
-    def _required_mori_dispatch_tokens_per_rank(self) -> int:
-        """Max tokens a single rank dispatches through MoRI in one forward."""
-        cfg = resolving_view(self)
-        return cfg.chunked_prefill_size
-
-    def _required_pplx_dispatch_tokens_per_rank(self) -> int:
-        """Max tokens a single rank dispatches through pplx in one forward."""
-        cfg = resolving_view(self)
-        required = cfg.chunked_prefill_size
-        if cfg.cuda_graph_max_bs_decode is not None:
-            required = max(required, cfg.cuda_graph_max_bs_decode)
-        return required
-
         # ===== END TO BE REFACTORED ====
 
-    def _is_mistral_native_format(self) -> bool:
-        """True iff the checkpoint requires load_format=mistral.
-
-        Looks for consolidated*.safetensors with no competing
-        model*.safetensors; when both weight formats ship in the
-        same checkpoint (e.g. Mistral-7B-Instruct-v0.3) the HF path is
-        preferred to avoid loading Mistral-named weights into an
-        HF-named architecture.
-
-        Name override: mistral-large-3 / mistral-small-4 /
-        leanstral always treat as Mistral-native when params.json
-        is present -- those families need Mistral weight loading
-        regardless of which weight files happen to be present.
-        """
-        cfg = resolving_view(self)
-        _MISTRAL_NATIVE_PATTERNS = (
-            "mistral-large-3",
-            "mistral-small-4",
-            "leanstral",
-        )
-        name_matches = any(
-            p in str(cfg.model_path).lower() for p in _MISTRAL_NATIVE_PATTERNS
-        )
-
-        def _check_format(has_params, has_consolidated, has_hf_weights) -> bool:
-            if has_params and name_matches:
-                return True
-            return has_consolidated and not has_hf_weights
-
-        if os.path.isdir(cfg.model_path):
-            return _check_format(
-                has_params=os.path.exists(os.path.join(cfg.model_path, "params.json")),
-                has_consolidated=bool(
-                    glob.glob(os.path.join(cfg.model_path, "consolidated*.safetensors"))
-                ),
-                has_hf_weights=bool(
-                    glob.glob(os.path.join(cfg.model_path, "model*.safetensors"))
-                ),
-            )
-
-        try:
-            from huggingface_hub import HfApi
-
-            files = {s.rfilename for s in HfApi().model_info(cfg.model_path).siblings}
-            return _check_format(
-                has_params="params.json" in files,
-                has_consolidated=any(
-                    f.startswith("consolidated") and f.endswith(".safetensors")
-                    for f in files
-                ),
-                has_hf_weights=any(
-                    f.startswith("model")
-                    and f.endswith(".safetensors")
-                    and "/" not in f
-                    for f in files
-                ),
-            )
-        except Exception:
-            return False
-
     LANGUAGE_MODEL_ONLY_ARCHITECTURES = ("MuseGlimmerForConditionalGeneration",)
 
     # The strided-layout Triton requirement is enforced via
@@ -4587,52 +4158,6 @@ class ServerArgs:
             return False
         return True
 
-    def get_model_config(self):
-        # Lazy init to avoid circular import
-        cfg = resolving_view(self)
-        from sglang.srt.configs.model_config import ModelConfig
-
-        memo = getattr(self, "_model_config", None)
-        if memo is not None:
-            # The key is the path this record carried when the cache was
-            # filled. The GGUF and ModelScope handlers declare a different
-            # `model_path`, and a configuration built before them describes
-            # another checkpoint. `ModelConfig` re-points its own `model_path`
-            # at the local pull directory when the weights sit behind an
-            # object-store URI, so its field is not the key. A configuration a
-            # fixture supplied carries no key and is handed back as it is.
-            built_from = getattr(self, "_model_config_built_from", None)
-            if built_from is None or built_from == cfg.model_path:
-                return memo
-
-        model_config = ModelConfig.from_server_args(self)
-        self._model_config = model_config
-        self._model_config_built_from = cfg.model_path
-        if model_config.is_hybrid_swa:
-            logger.info(
-                "Hybrid SWA model detected. architectures=%s",
-                model_config.hf_config.architectures,
-            )
-        return model_config
-
-    def _resolved(self):
-        """Read-only view of the resolving configuration: declared fields
-        resolve from the declaration stash."""
-
-        return resolved_view(self)
-
-    def _late_resolution(self, source: str, **fields) -> None:
-        """Resolve fields at the launcher's validation stage (pre-publish).
-
-        See ``arg_groups.overrides.declare_late_resolution``: the decision goes
-        to this instance's declaration stash, so every holder of it carries the
-        decision and publishes bags that answer with it. Refused outright once
-        the config is published.
-        """
-        from sglang.srt.arg_groups.overrides import declare_late_resolution
-
-        declare_late_resolution(self, source, **fields)
-
     def __setattr__(self, name, value):
         # Once resolution has finished the record is the READ-ONLY raw input
         # the config bags were projected from. Resolved config changes go to the bags via
@@ -4651,153 +4176,17 @@ class ServerArgs:
             )
         object.__setattr__(self, name, value)
 
-    def _resolved_attention_backends(self):
-        """Mid-resolution (prefill, decode) backends: reads through the pass
-        view so declared fields resolve from the declaration stash."""
-        from sglang.srt.arg_groups.overrides import (
-            attention_backends_of,
-        )
-
-        return attention_backends_of(resolved_view(self))
-
-    def get_attention_backends(self):
-        """The (prefill, decode) pair resolution decided.
-
-        Reads through the declaration stash, not the fields: the model-specific
-        overrides declare into the stash without writing the fields, so a field
-        read answers with what the operator typed.
-        """
-        return attention_backends_of(resolved_view(self))
-
-    def use_mla_backend(self):
-        from sglang.srt.configs.model_config import AttentionArch
-
-        model_config = self.get_model_config()
-        return model_config.attention_arch == AttentionArch.MLA
-
-    def is_attention_backend_not_set(self):
-        cfg = resolving_view(self)
-        return (
-            cfg.attention_backend is None
-            and cfg.prefill_attention_backend is None
-            and cfg.decode_attention_backend is None
-        )
-
     def enable_mamba_extra_buffer(self) -> bool:
         return mamba_extra_buffer_of(resolving_view(self))
 
     def enable_mamba_extra_buffer_lazy(self) -> bool:
         return mamba_extra_buffer_lazy_of(resolving_view(self))
 
-    @property
-    def max_speculative_num_draft_tokens(self) -> Optional[int]:
-        """Return the maximum draft-token count speculative decoding may use.
-
-        Memoized only once the record is resolved: an answer computed off a raw
-        record describes inputs resolution is about to rewrite (auto speculative
-        sizing fills `speculative_num_draft_tokens` in), and a cache filled that
-        early would keep answering with it.
-        """
-        cfg = resolving_view(self)
-
-        memo = self.__dict__.get("_max_speculative_num_draft_tokens")
-        if memo is not None:
-            return memo
-        if cfg.speculative_num_draft_tokens is None:
-            result = None
-        elif not cfg.speculative_adaptive:
-            result = cfg.speculative_num_draft_tokens
-        else:
-            from sglang.srt.speculative.adaptive_spec_params import (
-                resolve_candidate_steps_from_config,
-            )
-
-            candidate_steps = resolve_candidate_steps_from_config(
-                cfg_path=cfg.speculative_adaptive_config,
-            )
-            # TODO: adaptive spec currently requires topk=1, so each runtime
-            # state needs steps + 1 draft-token slots. Revisit this if topk>1
-            # is supported.
-            result = max(candidate_steps) + 1
-        if getattr(self, "_resolution_finished", False):
-            self._max_speculative_num_draft_tokens = result
-        return result
-
-    @property
-    def mamba_cache_chunk_size(self) -> int:
-        # For mamba cache with extra buffer, the chunk size is the max of FLA_CHUNK_SIZE
-        # (or mamba_chunk_size if it is defined in the model's config) and page_size.
-        # It is used to determine the caching point in a sequence during prefill.
-        # A pre-seeded `_mamba_cache_chunk_size` (fixtures supply one so a dummy
-        # model never loads an HF config) is honored as-is; otherwise the memo
-        # is only kept once the record is resolved, because `page_size` below
-        # is resolution-written.
-        if not hasattr(self, "_mamba_cache_chunk_size"):
-
-            try:
-                from sglang.kernels.ops.attention.fla.chunk_delta_h import (
-                    CHUNK_SIZE as FLA_CHUNK_SIZE,
-                )
-            except ImportError:
-                # Must match sglang.kernels.ops.attention.fla.chunk_delta_h.CHUNK_SIZE
-                FLA_CHUNK_SIZE = 64
-
-            hf_config = self.get_model_config().hf_config
-            chunk_size = getattr(hf_config, "mamba_chunk_size", FLA_CHUNK_SIZE)
-            page_size = resolved_view(self).page_size
-            assert (
-                max(chunk_size, page_size) % min(chunk_size, page_size) == 0
-            ), f"For SSM models, either chunk_size or page_size must be divisible by the other, got {chunk_size=}, {page_size=}"
-            if not getattr(self, "_resolution_finished", False):
-                return max(chunk_size, page_size)
-            self._mamba_cache_chunk_size = max(chunk_size, page_size)
-        return self._mamba_cache_chunk_size
-
     def check_server_args(self):
         from sglang.srt.arg_groups.validation_hook import check_server_args
 
         check_server_args(self)
 
-    def adjust_mem_fraction_for_vlm(self, model_config):
-        cfg = resolving_view(self)
-        vision_config = getattr(model_config.hf_config, "vision_config", None)
-        if vision_config is None:
-            return
-
-        # roughly reduce the mem_fraction_static base on params of Vit
-        original_server_arg_mem_fraction = cfg.mem_fraction_static
-        # a base mem_fraction_static factor for regular Vit
-        base_mem_fraction_reduction_ratio = 0.95
-
-        vit_num_layers = getattr(vision_config, "num_hidden_layers", 24)
-        vit_hidden_size = getattr(vision_config, "hidden_size", 1024)
-
-        # baseline ViT params (ViT-L/14)
-        baseline_vit_layers = 24
-        baseline_vit_hidden_size = 1024
-
-        # weight params count
-        current_complexity_score = vit_num_layers * (vit_hidden_size**2)
-        baseline_complexity_score = baseline_vit_layers * (baseline_vit_hidden_size**2)
-        complexity_ratio = (
-            current_complexity_score / baseline_complexity_score
-            if baseline_complexity_score > 0
-            else 1.0
-        )
-
-        # every time the complexity grows 100%, adjust final factor for 10%
-        sensitivity_scale = 0.1
-        dynamic_adjustment_factor = 1.0 - sensitivity_scale * (complexity_ratio - 1.0)
-        dynamic_adjustment_factor = max(0.8, min(1.05, dynamic_adjustment_factor))
-
-        final_overall_factor = (
-            base_mem_fraction_reduction_ratio * dynamic_adjustment_factor
-        )
-        self._declare(
-            "adjust_mem_fraction_for_vlm",
-            mem_fraction_static=original_server_arg_mem_fraction * final_overall_factor,
-        )
-
     @property
     def _parsed_modelexpress_config(self) -> dict:
         cache = getattr(self, "_mx_config_cache", None)
@@ -4952,10 +4341,6 @@ class ServerArgs:
             descriptor["load_topic"] = LOAD_TOPIC
         return descriptor
 
-    def should_report_expert_balancedness(self) -> bool:
-        cfg = resolving_view(self)
-        return cfg.expert_balancedness_report_mode != "off"
-
     def should_log_expert_balancedness_to_server_log(self) -> bool:
         cfg = resolving_view(self)
 

python/sglang/test/test_utils.py

@@ -2088,20 +2088,27 @@ def _wait_for_gpu_idle_in_ci(
             pass
 
 
+# Names the runner kits stamp onto a record that are not members of it.
+# `ModelRunner` computes `use_mla_backend` on itself; the kits copy that bool
+# onto the record they hand the runner, and `hasattr` cannot see it.
+_RUNNER_WRITTEN_NAMES = frozenset({"use_mla_backend"})
+
+
 def server_args_variant(server_args, **fields):
     """A modified deep copy of a config, for a test double whose fixture
     differs from the (possibly published, read-only) config it starts from.
     The receiver is untouched; the copy keeps its read-only guard.
 
-    A name may also shadow a method with a fixture value (the runner kits set
-    ``use_mla_backend``, a method ModelRunner itself overwrites at init);
-    names that exist nowhere on the class fail loudly."""
+    A name may also be one the kits stamp on rather than a field (see
+    ``_RUNNER_WRITTEN_NAMES``); names that exist nowhere fail loudly."""
     variant = copy.deepcopy(server_args)
     cls = type(variant)
     unknown = {
         name
         for name in fields
-        if name not in cls.__dataclass_fields__ and not hasattr(cls, name)
+        if name not in cls.__dataclass_fields__
+        and not hasattr(cls, name)
+        and name not in _RUNNER_WRITTEN_NAMES
     }
     if unknown:
         raise ValueError(f"unknown ServerArgs field(s): {sorted(unknown)}")

test/registered/cpu/test_server_args_backend.py

@@ -58,12 +58,12 @@ class TestServerArgsIBDeviceValidation(unittest.TestCase):
         real_listdir = os.listdir
 
         with patch(
-            "sglang.srt.server_args.os.path.isdir",
+            "sglang.srt.arg_groups.validation_hook.os.path.isdir",
             side_effect=lambda path: (
                 True if path == "/sys/class/infiniband" else real_isdir(path)
             ),
         ), patch(
-            "sglang.srt.server_args.os.listdir",
+            "sglang.srt.arg_groups.validation_hook.os.listdir",
             side_effect=lambda path: (
                 available_devices
                 if path == "/sys/class/infiniband"

test/registered/unit/configs/test_multimodal_piecewise_cuda_graph.py

@@ -88,8 +88,9 @@ class TestMultimodalPiecewiseCudaGraph(CustomTestCase):
                 "sglang.srt.arg_groups.cuda_graph_hook"
                 ".disable_tc_piecewise_cudagraph_if_incompatible"
             ) as disable_if_incompatible,
-            patch.object(
-                args, "_resolved_attention_backends", return_value=("fa3", "fa3")
+            patch(
+                "sglang.srt.arg_groups.overrides.attention_backends_of",
+                return_value=("fa3", "fa3"),
             ),
         ):
             apply_cuda_graph_compatibility(args)
@@ -116,12 +117,11 @@ class TestMultimodalPiecewiseCudaGraph(CustomTestCase):
         args._cuda_graph_config_locked = set()
 
         with (
-            patch.object(
-                args,
-                "_resolved_attention_backends",
+            patch(
+                "sglang.srt.arg_groups.overrides.attention_backends_of",
                 return_value=("trtllm_mla", "trtllm_mla"),
             ),
-            patch.object(args, "use_mla_backend", return_value=True),
+            patch("sglang.srt.arg_groups.overrides.use_mla_backend", return_value=True),
         ):
             apply_cuda_graph_compatibility(args)
 
@@ -137,9 +137,8 @@ class TestMultimodalPiecewiseCudaGraph(CustomTestCase):
         )
         args._cuda_graph_config_locked = {(Phase.PREFILL, "backend")}
 
-        with patch.object(
-            args,
-            "_resolved_attention_backends",
+        with patch(
+            "sglang.srt.arg_groups.overrides.attention_backends_of",
             return_value=("trtllm_mla", "trtllm_mla"),
         ):
             apply_cuda_graph_compatibility(args)
@@ -185,10 +184,7 @@ class TestMultimodalPiecewiseCudaGraph(CustomTestCase):
         args.disable_radix_cache = False
         args.chunked_prefill_size = 2048
 
-        with (
-            patch.object(args, "get_model_config", return_value=args._model_config),
-            patch("sglang.srt.arg_groups.model_hook.is_cuda", return_value=True),
-        ):
+        with (patch("sglang.srt.arg_groups.model_hook.is_cuda", return_value=True),):
             handle_model_capability_adjustments(args)
 
         self.assertTrue(resolution_result(args, "disable_radix_cache"))
@@ -215,7 +211,7 @@ class TestMultimodalPiecewiseCudaGraph(CustomTestCase):
             hf_config=SimpleNamespace(architectures=["BertModel"]),
         )
 
-        with patch.object(args, "get_model_config", return_value=args._model_config):
+        if True:  # the record already carries the seeded configuration
             handle_model_capability_adjustments(args)
 
         self.assertTrue(resolution_result(args, "is_embedding"))

test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py

@@ -87,7 +87,10 @@ from sglang.srt.mem_cache.unified_radix_cache import (
     _OngoingPrefetch,
     _OngoingWriteThrough,
 )
-from sglang.srt.runtime_context import get_server_args, get_serving
+from sglang.srt.runtime_context import (
+    get_serving,
+    mamba_cache_chunk_size,
+)
 from sglang.srt.sampling.sampling_params import SamplingParams
 from sglang.srt.server_args import (
     ServerArgs,
@@ -5225,7 +5228,7 @@ class UnifiedRadixCacheSuite:
         if not self.cfg.has_mamba or self.cfg.has_swa or self.cfg.page_size != 1:
             self.skipTest("requires page_size=1 Full+Mamba")
         cache, allocator, req_to_token_pool = build_fixture(self.cfg)
-        chunk_size = get_server_args().mamba_cache_chunk_size
+        chunk_size = mamba_cache_chunk_size()
         tokens = self._make_seq(1, chunk_size + 1)
         self._insert(cache, allocator, req_to_token_pool, tokens)
         leaf = cache.match_prefix(
@@ -5258,7 +5261,7 @@ class UnifiedRadixCacheSuite:
         if not self.cfg.has_mamba or self.cfg.has_swa or self.cfg.page_size != 1:
             self.skipTest("requires page_size=1 Full+Mamba")
         cache, allocator, req_to_token_pool = self._build_hicache_fixture()
-        chunk_size = get_server_args().mamba_cache_chunk_size
+        chunk_size = mamba_cache_chunk_size()
         prefix = self._make_seq(1, chunk_size)
         tokens = prefix + self._make_seq(1000, chunk_size + 1)
         self._insert(cache, allocator, req_to_token_pool, prefix)
@@ -5283,7 +5286,7 @@ class UnifiedRadixCacheSuite:
         if not self.cfg.has_mamba or self.cfg.has_swa or self.cfg.page_size != 1:
             self.skipTest("requires page_size=1 Full+Mamba")
         cache, allocator, req_to_token_pool = self._build_hicache_fixture()
-        chunk_size = get_server_args().mamba_cache_chunk_size
+        chunk_size = mamba_cache_chunk_size()
         prefix = self._make_seq(1, chunk_size)
         tokens = prefix + self._make_seq(1000, chunk_size + 1)
         self._insert(cache, allocator, req_to_token_pool, prefix)

test/registered/unit/model_executor/runner/test_flashinfer_autotune.py

@@ -50,10 +50,7 @@ def test_packed_speculative_extend_is_limited_to_pd_prefill_target(mode, error):
 
 def test_chunked_prefill_disabled_uses_legacy_token_ceiling():
     model_runner = SimpleNamespace(
-        server_args=SimpleNamespace(
-            max_prefill_buffer_tokens=Mock(return_value=0),
-            max_prefill_tokens=32768,
-        ),
+        server_args=SimpleNamespace(),
         is_generation=True,
         is_draft_worker=False,
         spec_algorithm=SimpleNamespace(is_speculative=lambda: False),
@@ -76,6 +73,12 @@ def test_chunked_prefill_disabled_uses_legacy_token_ceiling():
             "get_disagg",
             return_value=SimpleNamespace(disaggregation_mode="prefill"),
         ),
+        patch.object(flashinfer_autotune, "max_prefill_buffer_tokens", return_value=0),
+        patch.object(
+            flashinfer_autotune,
+            "get_schedule",
+            return_value=SimpleNamespace(max_prefill_tokens=32768),
+        ),
         patch.object(flashinfer_autotune, "run_flashinfer_autotune_forward"),
         patch.object(flashinfer_autotune.torch.cuda, "empty_cache"),
     ):

test/registered/unit/server_args/test_model_config_cache.py

@@ -1,4 +1,4 @@
-"""`get_model_config()` caches, and the key is the path the record carried.
+"""`model_config_of()` caches, and the key is the path the record carried.
 
 Two movements of a `model_path` reach this cache, and only the first one means
 the cached configuration describes the wrong checkpoint:
@@ -20,6 +20,7 @@ import tempfile
 import unittest
 from types import SimpleNamespace
 
+from sglang.srt.arg_groups.overrides import declare_resolution, model_config_of
 from sglang.srt.configs.model_config import ModelConfig
 from sglang.srt.environ import EnvField, envs
 from sglang.srt.server_args import ServerArgs
@@ -117,7 +118,7 @@ class TestTheModelConfigCache(CustomTestCase):
         self.assertEqual(server_args.model_path, _OBJECT_STORE_URI)
         self.assertEqual(cached.model_path, pulled)
 
-        self.assertIs(server_args.get_model_config(), cached)
+        self.assertIs(model_config_of(server_args), cached)
 
     def test_a_declared_model_path_rebuilds_the_configuration(self):
         """The GGUF and ModelScope shape: the record's own path moved."""
@@ -125,14 +126,15 @@ class TestTheModelConfigCache(CustomTestCase):
         second_checkpoint = self._checkpoint()
 
         server_args = ServerArgs(model_path=first_checkpoint, device="cuda")
-        first = server_args.get_model_config()
+        first = model_config_of(server_args)
         self.assertEqual(first.model_path, first_checkpoint)
 
-        server_args._declare(
+        declare_resolution(
+            server_args,
             "test_a_declared_model_path_rebuilds_the_configuration",
             model_path=second_checkpoint,
         )
-        second = server_args.get_model_config()
+        second = model_config_of(server_args)
         self.assertIsNot(second, first)
         self.assertEqual(second.model_path, second_checkpoint)
 
@@ -151,11 +153,11 @@ class TestTheModelConfigCache(CustomTestCase):
             model_path=second_checkpoint,
         )
 
-        rebuilt = copy_.get_model_config()
+        rebuilt = model_config_of(copy_)
         self.assertEqual(rebuilt.model_path, second_checkpoint)
-        self.assertIs(copy_.get_model_config(), rebuilt)
+        self.assertIs(model_config_of(copy_), rebuilt)
         # The parent keeps the configuration it resolved with.
-        self.assertEqual(server_args.get_model_config().model_path, first_checkpoint)
+        self.assertEqual(model_config_of(server_args).model_path, first_checkpoint)
 
     def test_a_supplied_configuration_is_handed_back(self):
         """A configuration nothing in here built carries no key, so nothing
@@ -164,7 +166,7 @@ class TestTheModelConfigCache(CustomTestCase):
         stand_in = SimpleNamespace(model_path="somewhere/else")
         server_args._model_config = stand_in
 
-        self.assertIs(server_args.get_model_config(), stand_in)
+        self.assertIs(model_config_of(server_args), stand_in)
 
 
 if __name__ == "__main__":

test/registered/unit/server_args/test_model_config_reads_resolved_input.py

@@ -30,7 +30,7 @@ _SRT = pathlib.Path(sglang.__file__).resolve().parent / "srt"
 # Two quantities sharing one name.
 _READ_BEFORE_RESOLUTION = frozenset({"is_embedding"})
 
-# Declared after the first `get_model_config()`, so the cached configuration
+# Declared after the first `model_config_of()`, so the cached configuration
 # holds the earlier value. Nothing reads the stale copy today (its one consumer
 # is on the `is_draft_model` branch, built after resolution), and fixing it
 # means moving the build or the hook. Pinned so a second field in this position
@@ -109,7 +109,7 @@ def _registry_collection_is_after_the_build():
 
     Handler-local ordering only -- the caller still has to compare against the
     pipeline-wide first build, which sits in an *earlier* step: hoisting the
-    collection above this handler's own `get_model_config()` call does not move
+    collection above this handler's own `model_config_of()` call does not move
     it above the configuration another handler already cached.
     """
     handler = None
@@ -145,7 +145,7 @@ def _registry_collection_is_after_the_build():
             name = func.id
         else:
             continue
-        if name == "get_model_config" and build is None:
+        if name == "model_config_of" and build is None:
             build = node.lineno
         if name == "collect_model_override_declarations" and collect is None:
             collect = node.lineno
@@ -192,11 +192,12 @@ def _server_args_names(tree, path):
                 and value.args[0].id in names
             )
             # `resolved = self._resolved()` is the same view, spelled as the
-            # record's own member.
+            # resolution vocabulary.
             member = (
                 isinstance(value, ast.Call)
                 and isinstance(value.func, ast.Attribute)
-                and value.func.attr == "_resolved"
+                and isinstance(value.func, ast.Name)
+                and value.func.id == "resolved_view"
                 and isinstance(value.func.value, ast.Name)
                 and value.func.value.id in names
             )
@@ -267,7 +268,7 @@ def _late_resolution_fields():
                 if isinstance(node.func, ast.Attribute)
                 else getattr(node.func, "id", "")
             )
-            if called in ("_late_resolution", "declare_late_resolution"):
+            if called == "declare_late_resolution":
                 fields |= {kw.arg for kw in node.keywords if kw.arg}
     return fields
 
@@ -488,14 +489,14 @@ def _declaration_positions():
     wanted = _constructor_reads()
 
     def build_site():
-        """(step index, method name, line) of the first `get_model_config()`."""
+        """(step index, method name, line) of the first `model_config_of()`."""
         for index, step in enumerate(steps):
             for method in reached[step]:
                 for node in ast.walk(methods[method]):
                     if (
                         isinstance(node, ast.Call)
-                        and isinstance(node.func, ast.Attribute)
-                        and node.func.attr == "get_model_config"
+                        and isinstance(node.func, ast.Name)
+                        and node.func.id == "model_config_of"
                     ):
                         return index, step, method, node.lineno
         return None
@@ -532,8 +533,8 @@ def _declaration_positions():
                 same_body = index == build_index and method == build_method
                 rank = 0 if same_body and node.lineno < build_line_in_body else 1
                 if (
-                    isinstance(node.func, ast.Attribute)
-                    and node.func.attr == "_declare"
+                    isinstance(node.func, ast.Name)
+                    and node.func.id == "declare_resolution"
                 ):
                     fields = {kw.arg for kw in node.keywords if kw.arg}
                 # A handler that calls an imported hook (the Kimi and DeepSeek
@@ -669,8 +670,8 @@ class TestModelConfigReadsResolvedInput(CustomTestCase):
             for method in reached[step]
             if any(
                 isinstance(node, ast.Call)
-                and isinstance(node.func, ast.Attribute)
-                and node.func.attr == "get_model_config"
+                and isinstance(node.func, ast.Name)
+                and node.func.id == "model_config_of"
                 for node in ast.walk(methods[method])
             )
         )

test/registered/unit/server_args/test_no_public_non_field_slot.py

@@ -61,7 +61,7 @@ class TestNoPublicNonFieldSlot(CustomTestCase):
         written = _self_written_attributes()
         self.assertGreater(
             len(written),
-            5,
+            3,
             f"only {len(written)} self-writes found; the scan is broken, not the "
             "record",
         )

test/registered/unit/server_args/test_page_major_backend_allowlist.py

@@ -30,6 +30,7 @@ under its own default configuration.
 """
 
 import unittest
+from unittest import mock
 
 from sglang.srt.arg_groups.kv_cache_hook import handle_page_major_kv_layout
 from sglang.srt.server_args import ServerArgs
@@ -66,13 +67,18 @@ def _accepts(
         "mamba_backend": "triton",
     }.items():
         object.__setattr__(sa, name, value)
-    sa.use_mla_backend = lambda: use_mla
-    sa._resolved_attention_backends = lambda: [backend]
-    try:
-        handle_page_major_kv_layout(sa)
-        return True
-    except AssertionError:
-        return False
+    # `use_mla_backend` asks the model configuration, which this stand-in has
+    # no room for; the case under test is what the handler does with the answer.
+    # The handler imports it inside the function, so the source module is
+    # where the patch has to go.
+    with mock.patch(
+        "sglang.srt.arg_groups.overrides.use_mla_backend", return_value=use_mla
+    ):
+        try:
+            handle_page_major_kv_layout(sa)
+            return True
+        except AssertionError:
+            return False
 
 
 class TestPageMajorBackendAllowlist(unittest.TestCase):

test/registered/unit/server_args/test_resolution_declarations.py

@@ -24,7 +24,6 @@ import unittest
 import unittest.mock
 
 import sglang
-from sglang.srt import server_args as server_args_module
 from sglang.srt.arg_groups.overrides import resolution_result
 from sglang.srt.server_args import ServerArgs
 from sglang.test.ci.ci_register import register_cpu_ci
@@ -147,7 +146,7 @@ def _late_resolvers():
                     if isinstance(node.func, ast.Attribute)
                     else getattr(node.func, "id", None)
                 )
-                if called in ("declare_late_resolution", "_late_resolution"):
+                if called == "declare_late_resolution":
                     return True
                 if called and reaches(called, seen):
                     return True
@@ -887,7 +886,9 @@ class TestResolutionDeclarations(CustomTestCase):
         # The pipeline asks the platform other questions on the way through
         # (whether it is out of tree, whether it supports piecewise capture),
         # and which of those it reaches depends on the host.
-        class _Plugin(type(server_args_module.current_platform)):
+        from sglang.srt.platforms import current_platform
+
+        class _Plugin(type(current_platform)):
             device_name = "oot"
 
             def apply_server_args_defaults(self, server_args):

test/registered/unit/server_args/test_resolution_is_reproducible.py

@@ -36,7 +36,7 @@ import unittest.mock
 import torch
 
 import sglang
-from sglang.srt.arg_groups.overrides import resolution_result
+from sglang.srt.arg_groups.overrides import model_config_of, resolution_result
 from sglang.srt.environ import EnvField, envs
 from sglang.srt.server_args import ServerArgs
 from sglang.srt.utils import is_cuda
@@ -519,7 +519,7 @@ class TestProgramsResolveBeforeReadingResolution(CustomTestCase):
         from sglang.srt.server_args import ServerArgs as _ServerArgs
 
         srt = pathlib.Path(next(iter(sglang.__path__))).resolve() / "srt"
-        declarers = {"_declare", "declare_resolution", "declare_late_resolution"}
+        declarers = {"declare_resolution", "declare_late_resolution"}
         fields = set()
         field_names = {field.name for field in _dataclasses.fields(_ServerArgs)}
         # The record plus every module under `arg_groups/`: a handler declares
@@ -826,10 +826,10 @@ class TestACopyStaysResolved(_RestoresProcessState, CustomTestCase):
     def test_the_copy_carries_what_resolution_left_on_the_record(self):
         """Not just the stash and the flag.
 
-        `get_model_config()` memoizes on the record, and that cache is filled
+        `model_config_of()` memoizes on the record, and that cache is filled
         during resolution. A copy that is marked resolved but arrives without it
         cannot fill it -- the read-only guard refuses the cache write -- so the
-        first `get_model_config()` raises. That is what killed the Ray
+        first `model_config_of()` raises. That is what killed the Ray
         schedulers, and it is why the carry is enumerated from the instance
         rather than from a list of names.
         """
@@ -846,7 +846,7 @@ class TestACopyStaysResolved(_RestoresProcessState, CustomTestCase):
             [],
             f"the copy did not carry what resolution left on the record: {missing}",
         )
-        self.assertIsNotNone(copy_.get_model_config())
+        self.assertIsNotNone(model_config_of(copy_))
         # Containers are copied, so the copy's declaration stays with it.
         self.assertEqual(
             len(parent._resolved_overrides) + 1, len(copy_._resolved_overrides)

test/registered/unit/server_args/test_resolution_reads_the_declarations.py

@@ -4,8 +4,8 @@
 nothing. The fields keep what the caller passed, so a resolver that reads a
 field another resolver may have decided reads the raw input -- silently, and
 only on the configurations where that other resolver fires. The whole pipeline
-therefore reads through `resolving_view` (or `ServerArgs._resolved()`, which is
-the same view spelled as the record's own member), and this pins that there is
+therefore reads through `resolving_view` (or `resolved_view`, which is
+the same view after resolution has finished), and this pins that there is
 nothing left reading a field directly.
 
 Subjects: every function in `arg_groups/` that takes a config, every
@@ -83,7 +83,6 @@ def _field_reads(fn, holders):
 
 _DECLARERS = frozenset(
     {
-        "_declare",
         "declare_resolution",
         "declare_late_resolution",
         "declare_direct_writes",
@@ -472,7 +471,7 @@ class TestResolutionReadsTheDeclarations(CustomTestCase):
         members = _record_members()
         # The floor is here to catch the scan collapsing, not to pin the
         # class's size.
-        self.assertGreater(len(members), 40, f"only {len(members)} members were found")
+        self.assertGreater(len(members), 25, f"only {len(members)} members were found")
         offenders = []
         for name, fn in sorted(members.items()):
             holders = _holders(fn) | {"self"}

test/registered/unit/server_args/test_server_args.py

@@ -37,7 +37,10 @@ from sglang.srt.arg_groups.moe_hook import (
     validate_deepep_v2_dispatch_token_budget,
     validate_deepep_v2_speculative_draft,
 )
-from sglang.srt.arg_groups.overrides import resolution_result
+from sglang.srt.arg_groups.overrides import (
+    cutedsl_moe_max_num_tokens,
+    resolution_result,
+)
 from sglang.srt.arg_groups.parallel_hook import (
     handle_context_parallelism,
     handle_data_parallelism,
@@ -825,9 +828,7 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
         )
         defaults.update(kw)
         view = ResolvedView(
-            SimpleNamespace(
-                get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-            )
+            SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
         )
         with (
             patch("sglang.srt.configs.model_config.is_deepseek_dsa", return_value=True),
@@ -845,21 +846,21 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
             ),
         }
 
-    @patch("sglang.srt.server_args.is_hip", return_value=False)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=False)
     def test_hisparse_defaults_to_flashmla_sparse_on_cuda_bfloat16(self, _mock_is_hip):
         resolved = self._resolve("bfloat16")
 
         self.assertEqual(resolved["dsa_prefill_backend"], "flashmla_sparse")
         self.assertEqual(resolved["dsa_decode_backend"], "flashmla_sparse")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=False)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=False)
     def test_hisparse_defaults_to_flashmla_kv_on_cuda_fp8(self, _mock_is_hip):
         resolved = self._resolve("fp8_e4m3")
 
         self.assertEqual(resolved["dsa_prefill_backend"], "flashmla_kv")
         self.assertEqual(resolved["dsa_decode_backend"], "flashmla_kv")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=False)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=False)
     def test_hisparse_accepts_flashinfer_sparse_mla_on_cuda_fp8(self, _mock_is_hip):
         """SM120 GLM DSA resolves both DSA backends to flashinfer_sparse_mla, so
         the fp8 hisparse allow-set must admit it or --enable-hisparse cannot
@@ -876,14 +877,14 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
         validate_hisparse_dsa_backend(server_args, "dsa_prefill_backend", "prefill")
         validate_hisparse_dsa_backend(server_args, "dsa_decode_backend", "decode")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=True)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=True)
     def test_hisparse_defaults_to_tilelang_on_rocm(self, _mock_is_hip):
         resolved = self._resolve("bfloat16")
 
         self.assertEqual(resolved["dsa_prefill_backend"], "tilelang")
         self.assertEqual(resolved["dsa_decode_backend"], "tilelang")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=True)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=True)
     def test_hisparse_preserves_rocm_user_backend_and_defaults_missing_side(
         self, _mock_is_hip
     ):
@@ -892,7 +893,7 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
         self.assertEqual(resolved["dsa_prefill_backend"], "tilelang")
         self.assertEqual(resolved["dsa_decode_backend"], "tilelang")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=True)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=True)
     def test_hisparse_accepts_aiter_backend_on_rocm(self, _mock_is_hip):
         server_args = ServerArgs(
             model_path="dummy",
@@ -905,7 +906,7 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
         validate_hisparse_dsa_backend(server_args, "dsa_prefill_backend", "prefill")
         validate_hisparse_dsa_backend(server_args, "dsa_decode_backend", "decode")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=True)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=True)
     def test_hisparse_rejects_cuda_backend_on_rocm(self, _mock_is_hip):
         server_args = ServerArgs(
             model_path="dummy",
@@ -917,7 +918,7 @@ class TestHiSparseDsaBackendPolicy(unittest.TestCase):
         with self.assertRaisesRegex(ValueError, "tilelang"):
             validate_hisparse_dsa_backend(server_args, "dsa_prefill_backend", "prefill")
 
-    @patch("sglang.srt.server_args.is_hip", return_value=False)
+    @patch("sglang.srt.arg_groups.hisparse_hook._is_hip", return_value=False)
     def test_hisparse_rejects_rocm_backend_on_cuda(self, _mock_is_hip):
         server_args = ServerArgs(
             model_path="dummy",
@@ -969,7 +970,7 @@ class TestFa4PageSizeAutoForce(CustomTestCase):
         args.prefill_attention_backend = prefill
         args.decode_attention_backend = decode
         args.page_size = page_size
-        # Short-circuit get_model_config(): the fa4 page_size branch only needs
+        # Short-circuit model_config_of(): the fa4 page_size branch only needs
         # use_mla_backend() (mocked) and is_sm100_supported() (mocked), not a
         # real model_config. Pre-set the attribute so get_model_config returns
         # early without touching ModelConfig.from_server_args.
@@ -978,7 +979,7 @@ class TestFa4PageSizeAutoForce(CustomTestCase):
         return args
 
     @patch("sglang.srt.arg_groups.overrides.is_sm100_supported", return_value=True)
-    @patch("sglang.srt.server_args.ServerArgs.use_mla_backend", return_value=False)
+    @patch("sglang.srt.arg_groups.overrides.use_mla_backend", return_value=False)
     def test_combined_attention_backend_fa4_forces_page_size_128(
         self, _mock_mla, _mock_sm100
     ):
@@ -993,7 +994,7 @@ class TestFa4PageSizeAutoForce(CustomTestCase):
         self.assertEqual(resolved_view(args).page_size, 128)
 
     @patch("sglang.srt.arg_groups.overrides.is_sm100_supported", return_value=True)
-    @patch("sglang.srt.server_args.ServerArgs.use_mla_backend", return_value=False)
+    @patch("sglang.srt.arg_groups.overrides.use_mla_backend", return_value=False)
     def test_explicit_prefill_fa4_forces_page_size_128(self, _mock_mla, _mock_sm100):
         # `--prefill-attention-backend fa4`: the previously-covered path.
         args = self._make_args(attention_backend=None, prefill="fa4", page_size=1)
@@ -1678,7 +1679,7 @@ class TestAdaptiveSpecArgs(CustomTestCase):
             args.speculative_adaptive = True
             args.speculative_adaptive_config = f.name
             args.device = "cuda"
-            args.get_model_config = lambda: SimpleNamespace(
+            args._model_config = SimpleNamespace(
                 hf_config=SimpleNamespace(
                     architectures=["LlamaForCausalLM"],
                     get_text_config=lambda: SimpleNamespace(),
@@ -1870,7 +1871,9 @@ class TestCudaGraphDisaggregationRoles(CustomTestCase):
         )
         with (
             patch("sglang.srt.utils.is_cuda", return_value=True),
-            patch.object(ServerArgs, "use_mla_backend", return_value=False),
+            patch(
+                "sglang.srt.arg_groups.overrides.use_mla_backend", return_value=False
+            ),
         ):
             handle_cuda_graph_config(args)
         return args
@@ -1943,7 +1946,9 @@ class TestPrefillCudaGraphLoRACompatibility(CustomTestCase):
         )
         with (
             patch("sglang.srt.utils.is_cuda", return_value=True),
-            patch.object(ServerArgs, "use_mla_backend", return_value=False),
+            patch(
+                "sglang.srt.arg_groups.overrides.use_mla_backend", return_value=False
+            ),
         ):
             handle_cuda_graph_config(args)
         return args
@@ -2007,7 +2012,9 @@ class TestBreakableCudaGraphMultimodalAllowlist(CustomTestCase):
         )
         with (
             patch("sglang.srt.utils.is_cuda", return_value=True),
-            patch.object(ServerArgs, "use_mla_backend", return_value=False),
+            patch(
+                "sglang.srt.arg_groups.overrides.use_mla_backend", return_value=False
+            ),
         ):
             handle_cuda_graph_config(args)
         return args
@@ -2096,7 +2103,7 @@ class TestCutedslMoeMaxNumTokens(CustomTestCase):
         return server_args
 
     def test_prefill_dominates_in_default_config(self):
-        self.assertEqual(self._args().cutedsl_moe_max_num_tokens(), 16384)
+        self.assertEqual(cutedsl_moe_max_num_tokens(self._args()), 16384)
 
     def test_speculative_decoding_scales_decode_bound(self):
         # decode bound 512 * 8 dominates the small prefill/piecewise bounds
@@ -2106,7 +2113,7 @@ class TestCutedslMoeMaxNumTokens(CustomTestCase):
             speculative_algorithm="EAGLE",
             speculative_num_draft_tokens=8,
         )
-        self.assertEqual(args.cutedsl_moe_max_num_tokens(), 4096)
+        self.assertEqual(cutedsl_moe_max_num_tokens(args), 4096)
 
     def test_piecewise_bound_excluded_when_disabled(self):
         args = self._args(
@@ -2114,7 +2121,7 @@ class TestCutedslMoeMaxNumTokens(CustomTestCase):
             disable_piecewise_cuda_graph=True,
             cuda_graph_max_bs=64,
         )
-        self.assertEqual(args.cutedsl_moe_max_num_tokens(), 512)
+        self.assertEqual(cutedsl_moe_max_num_tokens(args), 512)
 
 
 class TestSamplingBackendTokenOracleEnvGate(CustomTestCase):
@@ -2466,10 +2473,9 @@ class TestDeepEPv2Args(CustomTestCase):
             dp_size=8,
             enable_dp_attention=True,
         )
-        with patch.object(
-            ServerArgs,
-            "max_speculative_num_draft_tokens",
-            new=property(lambda _self: 16),
+        with patch(
+            "sglang.srt.arg_groups.moe_hook.max_speculative_num_draft_tokens",
+            return_value=16,
         ):
             with envs.SGLANG_DEEPEP_V2_NUM_MAX_DISPATCH_TOKENS_PER_RANK.override(128):
                 with self.assertRaisesRegex(ValueError, "tokens/request=16"):

test/registered/unit/spec/test_spec_cpu_overlap_constraint.py

@@ -20,7 +20,7 @@ def _make_spec_args(device: str, algorithm: str = "EAGLE", **overrides) -> Serve
     args.speculative_num_steps = 3
     args.speculative_eagle_topk = 1
     args.speculative_num_draft_tokens = 4
-    args.get_model_config = lambda: SimpleNamespace(
+    args._model_config = SimpleNamespace(
         hf_config=SimpleNamespace(
             architectures=["LlamaForCausalLM"],
             get_text_config=lambda: SimpleNamespace(),

test/registered/unit/test_chain_read_ratchet.py

@@ -40,7 +40,7 @@ _OWNERS = ("server_args.py", "runtime_context.py", "arg_groups/")
 # startup default wherever it is written, and `benchmark/` ships too.
 _READS_SCANNED = _PACKAGE
 
-_DECLARERS = ("_declare", "declare_resolution", "declare_late_resolution")
+_DECLARERS = ("declare_resolution", "declare_late_resolution")
 
 
 def _declared_by_keyword():
@@ -190,10 +190,10 @@ def _declared_by_registry_and_passes():
 
 
 def _declared_by_late_resolution():
-    """Keywords of `self._late_resolution(...)`, the fourth declarer spelling.
+    """Keywords of `declare_late_resolution(record, ...)`, the late spelling.
 
-    It forwards `**fields` to `declare_late_resolution`, so the keywords sit at
-    its call sites and a scan for the declarer's own name finds none of them.
+    The fields sit at the call sites rather than in the declarer, so a scan
+    that only knew the declarer's own definition would find none of them.
     """
     # The record plus `arg_groups/`: a hook calls it on the record it was
     # handed, so scanning the record's file alone finds nothing.
@@ -203,8 +203,8 @@ def _declared_by_late_resolution():
         for node in ast.walk(ast.parse(source.read_text(encoding="utf-8-sig"))):
             if (
                 isinstance(node, ast.Call)
-                and isinstance(node.func, ast.Attribute)
-                and node.func.attr == "_late_resolution"
+                and isinstance(node.func, ast.Name)
+                and node.func.id == "declare_late_resolution"
             ):
                 fields |= {keyword.arg for keyword in node.keywords if keyword.arg}
     return fields
@@ -540,13 +540,20 @@ class TestNoChainReadsOfResolvedConfig(CustomTestCase):
             len(by_late),
             3,
             f"only {len(by_late)} fields are declared late; the "
-            "`_late_resolution` keyword scan broke",
+            "`declare_late_resolution` keyword scan broke",
         )
-        # The three mechanisms are not the same set: if any became a subset of
-        # the keyword scan, that scan would be doing all the work and a
-        # regression in the others would be invisible.
+        # The data channel is not the keyword scan's subset: if it became one,
+        # that scan would be doing all the work and a regression here would be
+        # invisible. The late channel *is* a subset, and deliberately so --
+        # `declare_late_resolution` is a keyword declarer like the others now
+        # that the record hosts no forwarding member, so its own floor above is
+        # what pins it.
         self.assertTrue(by_data - by_keyword, "the data channel adds nothing")
-        self.assertTrue(by_late - by_keyword, "late resolution adds nothing")
+        self.assertTrue(
+            by_late <= by_keyword,
+            "late resolution declares outside the keyword channel; it is the "
+            "same spelling, so the two cannot disagree",
+        )
 
     def test_nothing_reads_a_resolved_field_off_a_borrowed_record(self):
         found = _chain_reads(_resolution_written())

test/registered/unit/test_model_overrides.py

@@ -15,6 +15,7 @@ from types import SimpleNamespace
 from typing import Optional
 from unittest.mock import patch
 
+from sglang.srt.arg_groups import attention_hook
 from sglang.srt.arg_groups import overrides as overrides_module
 from sglang.srt.arg_groups.arg_utils import A, Arg, resolvable_fields
 from sglang.srt.arg_groups.overrides import (
@@ -24,6 +25,7 @@ from sglang.srt.arg_groups.overrides import (
     validate_declarations,
 )
 from sglang.srt.configs.minicpm import MiniCPMHybridConfig
+from sglang.srt.configs.model_config import AttentionArch
 from sglang.srt.environ import envs
 from sglang.srt.runtime_context import (
     get_context,
@@ -357,14 +359,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             enable_dp_attention=enable_dp_attention,
             enable_hierarchical_cache=enable_hierarchical_cache,
         )
-        args.is_attention_backend_not_set = lambda: all(
-            backend is None
-            for backend in (
-                args.attention_backend,
-                args.prefill_attention_backend,
-                args.decode_attention_backend,
-            )
-        )
         mixer_types = []
         if sparse_attention:
             mixer_types.append("minicpm4")
@@ -456,7 +450,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             disaggregation_mode="null",
             enable_dp_attention=False,
             enable_hierarchical_cache=False,
-            is_attention_backend_not_set=lambda: True,
         )
         config = SimpleNamespace(
             has_minicpm_sparse_attention=True,
@@ -630,7 +623,11 @@ class TestGoldenModelOverrides(_IsolatedPublish):
 
     def test_minimax_m2_sm10x_nvfp4_uses_routed_trtllm(self):
         """MiniMax-M2 NVFP4 auto must avoid the unsupported plain TRT-LLM path."""
-        with patch.object(overrides_module, "is_sm100_supported", return_value=True):
+        # Every module that asks: the attention handler validates what the
+        # override family picks, and each holds its own import.
+        with patch.object(
+            overrides_module, "is_sm100_supported", return_value=True
+        ), patch.object(attention_hook, "is_sm100_supported", return_value=True):
             explicit = self._construct(
                 "MiniMaxM2ForCausalLM",
                 "llama",
@@ -765,8 +762,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 speculative_draft_attention_backend=None,
                 page_size=None,
                 mamba_radix_cache_strategy="auto",
-                is_attention_backend_not_set=lambda: True,
-                get_model_config=lambda: model_config,
+                _model_config=model_config,
             ),
             hf_config,
         )
@@ -971,7 +967,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
         server_args.speculative_algorithm = "DFLASH"
         server_args.prefill_attention_backend = "triton"
         server_args.speculative_draft_attention_backend = "fa3"
-        server_args.is_attention_backend_not_set = lambda: False
 
         with (
             patch.object(overrides_module, "is_blackwell_supported", return_value=True),
@@ -1093,7 +1088,9 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 _gpt_oss_overrides(
                     SimpleNamespace(
                         dtype="float16",
-                        is_attention_backend_not_set=lambda: False,
+                        attention_backend="triton",
+                        prefill_attention_backend=None,
+                        decode_attention_backend=None,
                     ),
                     SimpleNamespace(architectures=["GptOssForCausalLM"]),
                 )
@@ -1313,7 +1310,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
         # dual-chunk config: mismatched explicit backend raises verbatim
         def _mc(dual):
             return SimpleNamespace(
-                get_model_config=lambda: SimpleNamespace(
+                _model_config=SimpleNamespace(
                     hf_config=SimpleNamespace(dual_chunk_attention_config=dual)
                 ),
                 attention_backend="fa3",
@@ -1473,9 +1470,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 swa_full_tokens_ratio=ServerArgs.swa_full_tokens_ratio,
                 moe_a2a_backend="none",
                 moe_runner_backend="auto",
-                get_model_config=lambda: SimpleNamespace(
-                    is_fp4_experts=True, nvfp4_moe_meta=None
-                ),
+                _model_config=SimpleNamespace(is_fp4_experts=True, nvfp4_moe_meta=None),
             )
             defaults.update(kw)
             return SimpleNamespace(**defaults)
@@ -1527,12 +1522,10 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
         # FP8 checkpoints and non-CUDA platforms keep their platform-specific
         # auto-resolution paths.
-        fp8_model_config = lambda: SimpleNamespace(
-            is_fp4_experts=False, nvfp4_moe_meta=None
-        )
+        fp8_model_config = SimpleNamespace(is_fp4_experts=False, nvfp4_moe_meta=None)
         self.assertNotIn(
             "moe_runner_backend",
-            _deepseek_v4_overrides(_args(get_model_config=fp8_model_config), hf),
+            _deepseek_v4_overrides(_args(_model_config=fp8_model_config), hf),
         )
         self.assertNotIn(
             "moe_runner_backend",
@@ -1569,7 +1562,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
         self.assertEqual(
             _deepseek_v4_overrides(
                 _args(
-                    get_model_config=lambda: SimpleNamespace(
+                    _model_config=SimpleNamespace(
                         is_fp4_experts=False, nvfp4_moe_meta=object()
                     )
                 ),
@@ -1604,15 +1597,10 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 speculative_draft_attention_backend=None,
                 page_size=None,
                 mamba_radix_cache_strategy="auto",
-                get_model_config=lambda: mc,
+                _model_config=mc,
             )
             defaults.update(kw)
             args = SimpleNamespace(**defaults)
-            args.is_attention_backend_not_set = lambda: (
-                args.attention_backend is None
-                and args.prefill_attention_backend is None
-                and args.decode_attention_backend is None
-            )
             return args
 
         hf = _hf()
@@ -1725,9 +1713,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         with (
@@ -1821,9 +1807,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         with (
@@ -1952,15 +1936,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             ns = SimpleNamespace(**defaults)
-            ns.is_attention_backend_not_set = lambda: (
-                ns.attention_backend is None
-                and ns.prefill_attention_backend is None
-                and ns.decode_attention_backend is None
-            )
-            ns.get_attention_backends = lambda: (
-                ns.prefill_attention_backend or ns.attention_backend,
-                ns.decode_attention_backend or ns.attention_backend,
-            )
             return ns
 
         # nothing set: prefill defaults to flashinfer
@@ -1991,9 +1966,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         with (
@@ -2037,9 +2010,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             defaults = dict(kv_cache_dtype="auto", device="cuda")
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         self.assertEqual(
@@ -2078,9 +2049,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         with patch.object(overrides_module, "is_hip", return_value=True):
@@ -2148,9 +2117,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             return ResolvedView(
-                SimpleNamespace(
-                    get_model_config=lambda: SimpleNamespace(hf_config=hf), **defaults
-                )
+                SimpleNamespace(_model_config=SimpleNamespace(hf_config=hf), **defaults)
             )
 
         # arch guard: non-mamba arch declares nothing
@@ -2255,17 +2222,28 @@ class TestGoldenModelOverrides(_IsolatedPublish):
         def _args(default_backend, **kw):
             defaults = dict(
                 attention_backend=None,
-                _get_default_attn_backend=lambda **_: default_backend,
-                use_mla_backend=lambda: False,
-                get_model_config=lambda: None,
+                prefill_attention_backend=None,
+                decode_attention_backend=None,
                 mamba_radix_cache_strategy="auto",
                 disable_radix_cache=False,
                 speculative_algorithm=None,
             )
             defaults.update(kw)
-            return SimpleNamespace(**defaults)
+            args = SimpleNamespace(**defaults)
+            args.default_backend_for_test = default_backend
+            return args
 
-        with patch.object(overrides_module, "is_sm100_supported", return_value=True):
+        with patch.object(
+            overrides_module, "is_sm100_supported", return_value=True
+        ), patch.object(
+            overrides_module,
+            "get_default_attn_backend",
+            lambda server_args, **_: server_args.default_backend_for_test,
+        ), patch.object(
+            overrides_module, "use_mla_backend", return_value=False
+        ), patch.object(
+            overrides_module, "model_config_of", return_value=None
+        ):
             # radix on + no extra buffer + no spec -> page_size=1 path
             self.assertEqual(
                 _qwen3_5_hybrid_overrides(_args("trtllm_mha"), None),
@@ -2422,11 +2400,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             )
             defaults.update(kw)
             ns = SimpleNamespace(**defaults)
-            ns.is_attention_backend_not_set = lambda: (
-                ns.attention_backend is None
-                and ns.prefill_attention_backend is None
-                and ns.decode_attention_backend is None
-            )
             return ns
 
         hf = SimpleNamespace()
@@ -2475,6 +2448,9 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 prefill_attention_backend=None,
                 speculative_draft_attention_backend=None,
                 page_size=1,
+                # `use_mla_backend` reads the model configuration; a non-MLA
+                # one keeps these assertions about the page constraints.
+                _model_config=SimpleNamespace(attention_arch=None),
             )
             defaults.update(kw)
             return ResolvedView(SimpleNamespace(**defaults))
@@ -2533,7 +2509,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 _fa4_page_constraint(
                     _view(
                         attention_backend="fa4",
-                        use_mla_backend=lambda: False,
                         speculative_eagle_topk=None,
                     )
                 ),
@@ -2543,7 +2518,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 _fa4_page_constraint(
                     _view(
                         attention_backend="fa4",
-                        use_mla_backend=lambda: False,
                         speculative_eagle_topk=2,  # EAGLE topk>1 keeps default
                     )
                 ),
@@ -2554,7 +2528,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             _intel_xpu_page_constraint(
                 _view(
                     decode_attention_backend="intel_xpu",
-                    use_mla_backend=lambda: False,
                 )
             ),
             {"page_size": 128},
@@ -2563,7 +2536,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             _intel_xpu_page_constraint(
                 _view(
                     decode_attention_backend="intel_xpu",
-                    use_mla_backend=lambda: True,
+                    _model_config=SimpleNamespace(attention_arch=AttentionArch.MLA),
                     page_size=16,  # MLA decode accepts 16
                 )
             ),
@@ -2585,7 +2558,8 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             defaults = dict(
                 device="cuda",
                 attention_backend=None,
-                is_attention_backend_not_set=lambda: True,
+                prefill_attention_backend=None,
+                decode_attention_backend=None,
                 # keep the (now-absorbed) quant/moe blocks inert so these
                 # assertions stay attention-only
                 moe_runner_backend="triton",
@@ -2674,7 +2648,7 @@ class TestGoldenModelOverrides(_IsolatedPublish):
                 _quantization_explicitly_unset=False,
                 moe_a2a_backend="none",
                 moe_runner_backend="auto",
-                get_model_config=lambda: SimpleNamespace(
+                _model_config=SimpleNamespace(
                     hf_config=SimpleNamespace(
                         architectures=[arch], quantization_config=quant_cfg
                     )
@@ -2742,7 +2716,6 @@ class TestGoldenModelOverrides(_IsolatedPublish):
 
         def _args(**kw):
             defaults = dict(
-                is_attention_backend_not_set=lambda: True,
                 attention_backend=None,
                 prefill_attention_backend=None,
                 decode_attention_backend=None,
@@ -2869,7 +2842,9 @@ class TestGoldenModelOverrides(_IsolatedPublish):
             defaults = dict(
                 speculative_algorithm=None,
                 enable_hierarchical_cache=False,
-                is_attention_backend_not_set=lambda: False,
+                attention_backend="triton",
+                prefill_attention_backend=None,
+                decode_attention_backend=None,
             )
             defaults.update(kw)
             return SimpleNamespace(**defaults)

test/registered/unit/test_runtime_context.py

@@ -16,6 +16,18 @@ from unittest.mock import patch
 import sglang as _sglang
 import sglang.srt.server_args as server_args_module
 from sglang.srt.arg_groups.arg_utils import NS, A, Arg
+from sglang.srt.arg_groups.overrides import (
+    attention_backends_of,
+)
+from sglang.srt.arg_groups.overrides import (
+    mamba_cache_chunk_size as mamba_cache_chunk_size_of,
+)
+from sglang.srt.arg_groups.overrides import (
+    max_prefill_buffer_tokens as max_prefill_buffer_tokens_of,
+)
+from sglang.srt.arg_groups.overrides import (
+    resolved_view,
+)
 from sglang.srt.runtime_context import (
     Flags,
     ParallelContext,
@@ -404,7 +416,7 @@ class TestServerArgsScopedOverride(_IsolatedServerArgs):
         published = (
             get_context().override_server_args(_mamba_cache_chunk_size=64).install()
         )
-        self.assertEqual(published.mamba_cache_chunk_size, 64)
+        self.assertEqual(mamba_cache_chunk_size_of(published), 64)
 
     def test_installed_config_arms_the_strict_guard(self):
         # The published dummy must behave like a resolved config: bare writes
@@ -1156,7 +1168,7 @@ class TestDerivedPredicatesAgreeAcrossTiers(_IsolatedServerArgs):
                             )
                             get_context().set_server_args(args)
                             self.assertEqual(
-                                ServerArgs.max_prefill_buffer_tokens(args),
+                                max_prefill_buffer_tokens_of(args),
                                 max_prefill_buffer_tokens(),
                             )
 
@@ -1243,7 +1255,7 @@ class TestDerivedPredicatesAgreeAcrossTiers(_IsolatedServerArgs):
                         )
                         get_context().set_server_args(args)
                         self.assertEqual(
-                            ServerArgs.get_attention_backends(args),
+                            attention_backends_of(resolved_view(args)),
                             attention_backends(),
                         )
 

test/registered/unit/test_split_attention_backend_decisions.py

@@ -34,6 +34,7 @@ from sglang.test.test_utils import CustomTestCase
 register_cpu_ci(est_time=2, suite="base-a-test-cpu")
 
 import sglang
+from sglang.srt.arg_groups.overrides import attention_backends_of, resolved_view
 
 _PACKAGE_ROOT = Path(next(iter(sglang.__path__))) / "srt"
 
@@ -181,7 +182,7 @@ class TestSplitBackendsReachTheDecisions(CustomTestCase):
             ("decode_attention_backend", "flashinfer"),
         ):
             object.__setattr__(args, name, value)
-        self.assertIn("flashinfer", args.get_attention_backends())
+        self.assertIn("flashinfer", attention_backends_of(resolved_view(args)))
 
     def test_support_triton_is_the_regression_being_guarded(self):
         from sglang.srt.utils.common import support_triton

test/registered/unit/test_supplied_instance_exposure_ratchet.py

@@ -483,8 +483,8 @@ class TestSuppliedInstanceExposure(CustomTestCase):
                 tgts = [node.target]
             elif (
                 isinstance(node, ast.Call)
-                and isinstance(node.func, ast.Attribute)
-                and node.func.attr == "_declare"
+                and isinstance(node.func, ast.Name)
+                and node.func.id == "declare_resolution"
             ):
                 targets |= {
                     kw.arg
@@ -622,7 +622,7 @@ class TestSuppliedInstanceExposure(CustomTestCase):
         for path in sorted(root.rglob("*.py")):
             rel = path.relative_to(root).as_posix()
             source = path.read_text(encoding="utf-8-sig")
-            if "_late_resolution" not in source:
+            if "declare_late_resolution" not in source:
                 continue
             try:
                 tree = ast.parse(source)