[Refactor] Rename NSA → DSA: user-facing aliases, file/class/import rename (#25821)

Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
Cheng Wan
2026-05-20 00:18:04 -07:00
committed by GitHub
co-authored by Claude Sonnet 4.6
parent da6d549ab2
commit 8131641bc6
162 changed files with 11298 additions and 10740 deletions
@@ -33,7 +33,7 @@ rechecked recent merged and open optimization PRs through the GitHub CLI/API.
The vLLM torch.compile pass inventory is now split out in
[`vllm-torch-compile-fusions.md`](vllm-torch-compile-fusions.md). Stable
current-code families remain folded into the mainline rows below. New
status-sensitive rows were added for DeepSeek-V4, GLM5 NSA / PDL, NVFP4 MoE,
status-sensitive rows were added for DeepSeek-V4, GLM5 DSA / PDL, NVFP4 MoE,
torch.compile decode, vLLM DSV4, vLLM ROCm WMMA, and vLLM GPU/CPU sync-removal
work. Recheck PR state before treating an in-flight row as shipped.
@@ -53,13 +53,13 @@ work. Recheck PR state before treating an in-flight row as shipped.
| Fused QK RoPE reshape + KV cache write | `fused_qk_rope_reshape_and_cache*`<br>RoPE followed by reshape / cache DtoD | `python/sglang/srt/layers/attention/utils.py::fused_qk_rope_reshape_and_cache` | One Triton kernel applies RoPE to Q / K, reshapes cache layout, and writes K / V directly to paged cache | Treat separate RoPE + reshape + cache-write ladders as an existing attention-prep fusion family. |
| Fused RoPE + KV cache store | `fused_set_kv_buffer`<br>RoPE followed by KV-store, DtoD, or cache-write kernels | `python/sglang/jit_kernel/rope.py`<br>`python/sglang/srt/models/utils.py::enable_fused_set_kv_buffer` | Shared entrypoints can route to fused RoPE + KV-store or model-side `fused_set_kv_buffer` fast paths | Compare against the fused cache-store path before proposing a new KV rewrite. |
| Fused decode metadata setup | `normal_decode_set_metadata`<br>`cache_seqlens_int32`<br>`cu_seqlens_k`<br>`page_table`<br>`swa_page_table` | `python/sglang/srt/layers/attention/flashattention_backend.py::normal_decode_set_metadata` | Triton decode path fuses seq-len cast/add, prefix-sum, req-to-token gather, page-table divide, and optional SWA metadata build into 1-2 kernels | If decode exposes multiple tiny metadata kernels before attention, first compare against this existing fused metadata-prep path. |
| NSA fused metadata copy for graph replay | `fused_metadata_copy`<br>`fused_metadata_copy_multi`<br>`fused_nsa_cache_seqlens`<br>`fused_flashmla_metadata` | `python/sglang/jit_kernel/fused_metadata_copy.py` | CUDA graph replay path fuses multiple metadata copies into one kernel or one multi-destination kernel | Treat bursts of tiny metadata-copy kernels around NSA replay as a missed existing replay fusion. |
| DSA fused metadata copy for graph replay | `fused_metadata_copy`<br>`fused_metadata_copy_multi`<br>`fused_dsa_cache_seqlens`<br>`fused_flashmla_metadata` | `python/sglang/jit_kernel/fused_metadata_copy.py` | CUDA graph replay path fuses multiple metadata copies into one kernel or one multi-destination kernel | Treat bursts of tiny metadata-copy kernels around DSA replay as a missed existing replay fusion. |
| DeepSeek MLA fused projection + norm + RoPE | `qkv_proj_with_rope_fused_weight`<br>`fused_qkv_a_proj_with_mqa`<br>`forward_absorb_fused_mla_rope*` | `python/sglang/srt/models/deepseek_common/attention_forward_methods/forward_mla_fused_rope_cpu.py`<br>`python/sglang/srt/models/deepseek_common/attention_forward_methods/forward_mla_fused_rope_rocm.py`<br>`python/sglang/srt/models/deepseek_v2.py` | CPU / ROCm paths fuse DeepSeek MLA projection packing with q / k norm, RoPE, and cache-oriented MLA prep | For DeepSeek MLA, split proj / norm / rope prep is usually an existing backend-specific fuse that did not fire. |
| Fused QK RoPE concat + MLA cache write | `fused_qk_rope_cat_and_cache_mla`<br>`set_mla_kv_buffer` | `python/sglang/srt/layers/rocm_linear_utils.py`<br>`python/sglang/srt/models/deepseek_common/attention_forward_methods/forward_mla.py` | ROCm MLA path can fuse Q / K RoPE packing, concat, and MLA cache write in one backend-specific op | On DeepSeek / MLA traces, separate RoPE-cat-cache steps are not automatically novel. |
| Qwen3 decode fused QK norm + 3D mRoPE + KV cache write | `fused_qk_norm_mrope_3d_cache_pts_quant_shuffle`<br>`mrope`<br>decode cache write | `python/sglang/srt/models/qwen3.py` | ROCm / AITER decode path fuses QK norm, 3D mRoPE, and paged KV cache write | On Qwen3-style decode, separate norm + mRoPE + cache-store kernels are not a novel opportunity. |
| NPU fused split-QKV + RMSNorm + RoPE | `split_qkv_rmsnorm_rope` | `python/sglang/srt/models/llama.py`<br>`python/sglang/srt/models/qwen3.py`<br>`python/sglang/srt/models/qwen3_moe.py`<br>`python/sglang/srt/models/glm4_moe.py` | Ascend path fuses QKV split, Q / K RMSNorm, and RoPE in one op | On NPU traces, separate split / norm / rope kernels usually mean the fused path is unavailable or bypassed. |
| Fused FP8 quantize + paged KV cache write | `trtllm_fp8_kv_kernel`<br>`fp8 kv cache write`<br>`paged KV cache write` | `python/sglang/srt/layers/attention/triton_ops/trtllm_fp8_kv_kernel.py` | TRTLLM MHA path fuses FP8 quantization, scale computation, and paged K / V cache write | If FP8 KV cache traces show standalone quant plus write kernels, first compare against this existing Triton fuse. |
| Fused MLA KV cache write + FP8 quant | `set_mla_kv_buffer_fp8_quant*`<br>`set_mla_kv_buffer_triton_fp8_quant` | `python/sglang/srt/mem_cache/utils.py`<br>`python/sglang/srt/mem_cache/memory_pool.py` | MLA / NSA KV pool path can quantize K and write directly into KV storage without a separate concat-and-quant chain | Treat standalone quant + KV-buffer write on MLA paths as missing existing fusion first. |
| Fused MLA KV cache write + FP8 quant | `set_mla_kv_buffer_fp8_quant*`<br>`set_mla_kv_buffer_triton_fp8_quant` | `python/sglang/srt/mem_cache/utils.py`<br>`python/sglang/srt/mem_cache/memory_pool.py` | MLA / DSA KV pool path can quantize K and write directly into KV storage without a separate concat-and-quant chain | Treat standalone quant + KV-buffer write on MLA paths as missing existing fusion first. |
| Fused MoE router / top-k / softcapping | `FusedMoeRouter`<br>`fused_moe_router*`<br>router GEMM + `topk` + `tanh` | `python/sglang/srt/layers/moe/router.py` | Single fused router kernel covers router matmul, softcapping, and top-k selection | Treat exposed router matmul + softcap + top-k chains as an existing MoE fusion family. |
| Fused MoE grouped-topk / gate kernels | `fused_topk_deepseek`<br>`moe_fused_gate`<br>`aiter_fused_topk`<br>`kimi_k2_moe_fused_gate` | `python/sglang/srt/layers/moe/topk.py` | CUDA / ROCm / FlashInfer kernels fuse bias, grouped-topk, renorm, and routed scaling into one gate op | Check backend / model eligibility before proposing a novel router-gate fusion. |
| Qwen-style shared-expert append into routed top-k output | `_append_shared_to_topk_output`<br>`fused_append_shared_experts_with_weights`<br>`num_fused_shared_experts` | `python/sglang/srt/models/qwen2_moe.py`<br>`python/sglang/srt/layers/moe/moe_runner/triton_utils/fused_moe_triton_kernels.py` | Qwen-style MoE paths can append shared-expert ids and sigmoid gate weights to routed top-k output in one Triton kernel so the shared experts execute inside the fused MoE path | Treat routed top-k plus shared-expert pad / concat ladders as an existing MoE-prep fusion family first. |
@@ -67,8 +67,8 @@ work. Recheck PR state before treating an in-flight row as shipped.
| Fused MoE sum + all-reduce | routed MoE followed by explicit sum-reduce kernels | `python/sglang/srt/layers/moe/fused_moe_triton/fused_moe.py`<br>`python/sglang/srt/layers/moe/fused_moe_triton/fused_moe_triton_kernels.py` | `fuse_sum_all_reduce=True` path in the second MoE GEMM | Before inventing a new MoE reduction fuse, check whether `enable_fused_moe_sum_all_reduce` is simply off or the quant path is incompatible. |
| Fused MoE activation + quant / re-quant | `silu_and_mul_*quant*`<br>`npu_dequant_swiglu_quant`<br>`swiglu_quant` | `python/sglang/srt/layers/moe/ep_moe/kernels.py`<br>`python/sglang/jit_kernel/nvfp4.py`<br>`python/sglang/srt/layers/moe/cutlass_w4a8_moe.py`<br>`python/sglang/srt/hardware_backend/npu/quantization/fused_moe_method_npu.py` | Quantized MoE backends fuse SwiGLU / SiLU-and-mul with FP8 / FP4 / NPU re-quant before the second expert GEMM | If MoE traces show standalone activation then quant kernels, first check whether the quantized fused path is missing. |
| DeepSeek comm-prep fused RMSNorm + quant / flatten-quant | `fused_rms_fp8_group_quant`<br>`fused_rms_mxfp4_quant`<br>`fused_flatten_fp8_group_quant`<br>`fused_flatten_mxfp4_quant` | `python/sglang/srt/layers/communicator.py`<br>`python/sglang/srt/models/deepseek_common/attention_forward_methods/forward_mla.py`<br>`python/sglang/srt/models/deepseek_common/attention_forward_methods/forward_mha.py` | DeepSeek MLA / MHA ROCm paths fuse RMSNorm or flatten with FP8 / MXFP4 quantization for comm / attention prep | On DeepSeek quant traces, split norm + quant or flatten + quant is an existing family, not a new idea. |
| NSA fused top-k transform / page-table build | `fast_topk_transform_fused`<br>`fast_topk_transform_ragged_fused` | `python/sglang/srt/layers/attention/nsa_backend.py` | NSA can fuse top-k selection with paged / ragged index transform instead of separate top-k plus metadata scatter | If NSA top-k metadata work is split, check `SGLANG_NSA_FUSE_TOPK` and backend support first. |
| NSA fused quantize + indexed K-cache store | `fused_store_index_k_cache`<br>`act_quant`<br>`index_k_with_scale_buffer` | `python/sglang/jit_kernel/fused_store_index_cache.py`<br>`python/sglang/srt/layers/attention/nsa/nsa_indexer.py` | Single JIT kernel quantizes bf16 K to fp8 + scale and writes directly into NSA index cache | Treat split `act_quant` + buffer-store on CUDA as missing an existing fused store path. |
| DSA fused top-k transform / page-table build | `fast_topk_transform_fused`<br>`fast_topk_transform_ragged_fused` | `python/sglang/srt/layers/attention/dsa_backend.py` | DSA can fuse top-k selection with paged / ragged index transform instead of separate top-k plus metadata scatter | If DSA top-k metadata work is split, check `SGLANG_DSA_FUSE_TOPK` and backend support first. |
| DSA fused quantize + indexed K-cache store | `fused_store_index_k_cache`<br>`act_quant`<br>`index_k_with_scale_buffer` | `python/sglang/jit_kernel/fused_store_index_cache.py`<br>`python/sglang/srt/layers/attention/dsa/dsa_indexer.py` | Single JIT kernel quantizes bf16 K to fp8 + scale and writes directly into DSA index cache | Treat split `act_quant` + buffer-store on CUDA as missing an existing fused store path. |
| Fused sampling temperature + softmax | `fused_temperature_softmax*` | `python/sglang/srt/layers/fused_sampling.py`<br>`python/sglang/srt/layers/sampler.py` | Triton single-pass / multi-pass kernels fuse temperature scaling and softmax during decode | Separate temp-divide + softmax at decode batch sizes is often a missed existing fusion. |
| Fused logit softcap | `fused_softcap`<br>`final_logit_softcapping` | `python/sglang/srt/layers/elementwise.py`<br>`python/sglang/srt/layers/logits_processor.py` | Triton kernels fuse cast-to-float and softcap / tanh math for logits or generic elementwise softcapping | Treat exposed cast + softcap ladders as an existing Triton fuse family. |
| Linear-attention packed projection reshuffle | `fused_qkvzba_split_reshape_cat*`<br>`qkvz_proj`<br>`ba_proj`<br>`qkvabz_proj`<br>`fused_qkvbfg_a_proj` | `python/sglang/jit_kernel/triton/gdn_fused_proj.py`<br>`python/sglang/srt/models/qwen3_next.py`<br>`python/sglang/srt/models/qwen3_5.py`<br>`python/sglang/srt/models/kimi_linear.py`<br>`python/sglang/srt/models/jet_nemotron.py` | GDN / Kimi / Jet-style linear-attn models pack multiple projections, then fuse split / reshape / cat into one kernel | Treat split reshape / transpose / cat ladders as an existing linear-attention fusion family. |
@@ -90,7 +90,7 @@ work. Recheck PR state before treating an in-flight row as shipped.
| Llama4 shared branch vs routed branch overlap | shared expert branch plus routed MoE branch as adjacent windows | `python/sglang/srt/models/llama4.py` | shared expert on current stream, router + topk + routed experts on `alt_stream` | Use Llama4 as the first precedent for branch-level overlap in similar sparse models. |
| ExaoneMoE shared experts vs router experts overlap | shared expert output and router-expert output form a two-branch window | `python/sglang/srt/models/exaone_moe.py::forward_normal_dual_stream` | shared experts on current stream, router + routed experts on `alt_stream`, explicit join before combine | This is an existing dual-stream MoE overlap family. |
| Grok residual-MoE branch overlap | dense MLP and block-sparse MoE branches in parallel | `python/sglang/srt/models/grok.py::moe_with_rmoe` | dense MLP on current stream, MoE on `alt_stream`, fused dual residual RMSNorm around boundaries | Treat exposed Grok branch overlap as an existing pattern. |
| NSA dual-stream overlap | Q-proj, K-proj, RoPE, cache-store, quantization in tight two-stream windows | `python/sglang/srt/layers/attention/nsa/nsa_indexer.py` | Q / K projection split, RoPE split, cache-store vs quantization overlap | NSA already contains several dual-stream overlap precedents. |
| DSA dual-stream overlap | Q-proj, K-proj, RoPE, cache-store, quantization in tight two-stream windows | `python/sglang/srt/layers/attention/dsa/dsa_indexer.py` | Q / K projection split, RoPE split, cache-store vs quantization overlap | DSA already contains several dual-stream overlap precedents. |
| MoriEP async dispatch / combine comm stream | `MoriEP`<br>`_comm_stream`<br>`dispatch`<br>`combine`<br>`done_event` | `python/sglang/srt/layers/moe/token_dispatcher/moriep.py` | MoriEP can submit dispatch and combine onto a dedicated communication stream and synchronize only through events | Treat MoriEP comm / compute interleave as an existing MoE overlap family. |
| Heterogeneous-TP staging scatter overlap | `scatter_stream`<br>`_scatter_stream`<br>`staging` | `python/sglang/srt/disaggregation/common/staging_handler.py`<br>`python/sglang/srt/disaggregation/common/staging_buffer.py` | decode-side staging scatter kernels can run on a dedicated stream while forward continues on the main stream | If decode traces show staging scatter kernels adjacent to forward kernels, classify them against this existing overlap family first. |
| Generic `alt_stream` overlap families | `alt_stream` plus explicit `wait_stream` / `with torch.cuda.stream(...)` | `qwen2_moe.py`<br>`qwen3_moe.py`<br>`glm4_moe.py`<br>`bailing_moe.py`<br>`llada2.py`<br>`grok.py`<br>`olmo2.py`<br>`step3p5.py`<br>`longcat_flash.py`<br>`falcon_h1.py` | model-specific overlap on attention prep, MoE branches, or cache-store | Search these families before designing a new overlap scheme from scratch. |
@@ -134,16 +134,16 @@ Stable entries should be folded into the mainline family rows above.
| Pattern | Trace keywords | Primary code | Existing path | Skill should conclude |
| --- | --- | --- | --- | --- |
| PR `#21877` fused grouped down-GEMM + combine | `grouped_gemm_nt_masked`<br>`combine`<br>`fused grouped gemm combine` | `PR #21877`<br>`python/sglang/srt/layers/moe/ep_moe/flashinfer_cutedsl_moe.py`<br>`python/sglang/srt/layers/moe/token_dispatcher/deepep.py` | FlashInfer CuTeDSL kernel fuses the second expert GEMM with DeepEP low-latency combine | Treat this as a concrete upstream MoE fuse / overlap family, not a new thought experiment. |
| PR `#21889` fused BF16 to FP4 quant + paged KV write | `set_mla_kv_buffer_fp4_quant_kernel`<br>`fp4 kv cache` | `PR #21889`<br>`python/sglang/srt/mem_cache/utils.py` | Triton kernel writes FP4 NSA KV pages directly while quantizing BF16 input | If NSA FP4 KV paths are split into quant plus store, classify them as an in-flight upstream fuse family. |
| PR `#21889` fused FP4 paged dequant to FP8 + page-table remap | `_dequant_fp4_to_fp8_paged_kernel`<br>`WRITE_PT`<br>`dequant_fp4_paged_decode` | `PR #21889`<br>`python/sglang/srt/layers/attention/nsa/dequant_fp4_to_fp8.py` | Triton kernel reads FP4 pages, writes FP8 directly, and can fuse decode-side page-table remap | Treat this as an upstream in-flight decode-prep fusion family. |
| PR `#21889` fused BF16 to FP4 quant + paged KV write | `set_mla_kv_buffer_fp4_quant_kernel`<br>`fp4 kv cache` | `PR #21889`<br>`python/sglang/srt/mem_cache/utils.py` | Triton kernel writes FP4 DSA KV pages directly while quantizing BF16 input | If DSA FP4 KV paths are split into quant plus store, classify them as an in-flight upstream fuse family. |
| PR `#21889` fused FP4 paged dequant to FP8 + page-table remap | `_dequant_fp4_to_fp8_paged_kernel`<br>`WRITE_PT`<br>`dequant_fp4_paged_decode` | `PR #21889`<br>`python/sglang/srt/layers/attention/dsa/dequant_fp4_to_fp8.py` | Triton kernel reads FP4 pages, writes FP8 directly, and can fuse decode-side page-table remap | Treat this as an upstream in-flight decode-prep fusion family. |
| PR `#21491` FlashInfer TRTLLM FP8 MoE with fused shared experts | `num_fused_shared_experts`<br>`trtllm_fp8_block_scale_moe` | `PR #21491`<br>`python/sglang/srt/layers/moe/fused_moe_triton/fused_moe.py`<br>`python/sglang/srt/models/deepseek_v2.py` | FlashInfer TRTLLM FP8 MoE path can fuse shared experts inside the routed MoE kernel | On FP8 TRTLLM MoE discussions, treat fused shared experts as an upstream pattern that already has a concrete PR. |
| PR `#22005` fused add + RMSNorm + per-token FP8 quant | `fused_add_rmsnorm_per_token_quant`<br>`per_token_quant_fp8` | `PR #22005`<br>`python/sglang/jit_kernel/csrc/elementwise/fused_add_rmsnorm_per_token_quant.cuh`<br>`python/sglang/jit_kernel/fused_add_rmsnorm_per_token_quant.py` | CUDA JIT kernel keeps normed values in registers and emits BF16 + FP8 outputs plus per-token scales | If FP8 online-quant traces show add+norm followed by per-token quant, treat this as an in-flight upstream CUDA fuse family. |
| PR `#20667` Qwen3.5 fused QK norm + RoPE + KV cache write | `fused_qk_norm_rope_cache_pts_quant_shuffle`<br>`fused_qk_norm_mrope_3d_cache_pts_quant_shuffle`<br>`rotary_dim` | `PR #20667`<br>`python/sglang/srt/models/qwen3_5.py`<br>`python/sglang/srt/models/utils.py` | ROCm / AITER path fuses Q / K RMSNorm, partial or 3D RoPE, and direct KV cache write for Qwen3.5 attention | Treat split QK-norm + RoPE + cache-store on Qwen3.5 as a concrete in-flight upstream family, not a novel idea. |
| PR `#22392` CUTLASS FP8 GEMM replacing nvjet | `cutlass_scaled_mm`<br>`fp8_scaled_mm`<br>`nvjet`<br>`cudaMemsetAsync` | `PR #22392`<br>`sgl-kernel/python/sgl_kernel/gemm.py`<br>`python/sglang/srt/layers/quantization/fp8_utils.py` | Runtime replacement swaps nvjet FP8 GEMMs for CUTLASS kernels, removing per-launch memset bubbles and extra output-copy kernels | Treat nvjet GEMM + memset bubble ladders as an in-flight SGLang linear-kernel family before calling them novel. |
| PR `#18612` NVFP4 CUTLASS MoE fused SiLU+Mul+quant | `silu_and_mul_scaled_nvfp4`<br>`nvfp4 expert quant`<br>`cutlass moe` | `PR #18612`<br>`python/sglang/srt/layers/moe/cutlass_w4a8_moe.py`<br>`python/sglang/jit_kernel/nvfp4.py` | Fuses MoE activation epilogue and NVFP4 expert quantization before the CUTLASS MoE second GEMM | Treat split SiLU+Mul then NVFP4 expert quant in CUTLASS MoE traces as an in-flight upstream SGLang family. |
| PR `#22918` FlashInfer per-token NVFP4 MoE | `per_token_nvfp4`<br>`trtllm_fp4_block_scale_moe`<br>`FlashInfer MoE` | `PR #22918`<br>`python/sglang/srt/layers/moe/fused_moe_triton/fused_moe.py` | Adds FlashInfer-backed per-token NVFP4 MoE execution so expert quant/dequant work can move into the fused MoE backend | Treat standalone per-token NVFP4 MoE support kernels as a candidate missing backend-selection path, not an automatically novel kernel idea. |
| PR `#22851` NSA top-k backend and FlashInfer / PyTorch top-k split | `nsa topk`<br>`flashinfer_topk`<br>`pytorch_topk`<br>`fast_topk_transform` | `PR #22851`<br>`python/sglang/srt/layers/attention/nsa_backend.py` | Makes NSA top-k backend selection explicit and aligns fused top-k transform with FlashInfer / PyTorch fallbacks | When NSA top-k dominates decode, first classify it as backend selection or fused-transform eligibility work. |
| PR `#24125` GLM5 NSA decode CatArrayBatchedCopy removal | `CatArrayBatchedCopy`<br>`GLM-5`<br>`NSA`<br>`TileLang decode` | `PR #24125`<br>`python/sglang/srt/layers/attention/nsa_backend.py` | Skips redundant cat/copy work in the GLM5 NSA TileLang decode path | Treat cat/copy bursts in GLM5 NSA decode as a concrete in-flight cleanup opportunity. |
| PR `#22851` DSA top-k backend and FlashInfer / PyTorch top-k split | `dsa topk`<br>`flashinfer_topk`<br>`pytorch_topk`<br>`fast_topk_transform` | `PR #22851`<br>`python/sglang/srt/layers/attention/dsa_backend.py` | Makes DSA top-k backend selection explicit and aligns fused top-k transform with FlashInfer / PyTorch fallbacks | When DSA top-k dominates decode, first classify it as backend selection or fused-transform eligibility work. |
| PR `#24125` GLM5 DSA decode CatArrayBatchedCopy removal | `CatArrayBatchedCopy`<br>`GLM-5`<br>`DSA`<br>`TileLang decode` | `PR #24125`<br>`python/sglang/srt/layers/attention/dsa_backend.py` | Skips redundant cat/copy work in the GLM5 DSA TileLang decode path | Treat cat/copy bursts in GLM5 DSA decode as a concrete in-flight cleanup opportunity. |
| PR `#24007` MoE LoRA virtual experts for csgmv backend | `csgmv`<br>`virtual experts`<br>`MoE LoRA`<br>`fused_moe_lora` | `PR #24007`<br>`python/sglang/srt/layers/lora_backend.py`<br>`python/sglang/srt/layers/moe` | Routes MoE LoRA adapter work through virtual experts so csgmv-style kernels can batch it instead of launching fragmented adapter work | Treat MoE-LoRA tiny-kernel ladders as an in-flight batching/fusion family. |
| PR `#24150` torch.compile local decode support | `enable_torch_compile`<br>`local compile`<br>`decode compile`<br>`torchinductor` | `PR #24150`<br>`python/sglang/srt` | Extends SGLang torch.compile coverage to local decode regions, so Inductor-generated fusion may replace hand-authored tiny kernels | When decode traces show compiler-generated kernels or missing named fused kernels, check this in-flight compile path before calling the shape unsupported. |
@@ -294,7 +294,7 @@ contain the same implementation.
| `enable_single_batch_overlap` | `python/sglang/srt/server_args.py` | Enables the SBO family. |
| `enable_fused_moe_sum_all_reduce` | `python/sglang/srt/server_args.py` | Enables fused MoE sum-reduce in the down path. |
| `SGLANG_BLACKWELL_OVERLAP_SHARED_EXPERTS_OUTSIDE_SBO` | `python/sglang/srt/environ.py` | Alters how DeepSeek-style shared-expert overlap behaves on Blackwell. |
| `SGLANG_NSA_FUSE_TOPK` | `python/sglang/srt/environ.py` | Gates NSA fused top-k transform / page-table build. |
| `SGLANG_DSA_FUSE_TOPK` | `python/sglang/srt/environ.py` | Gates DSA fused top-k transform / page-table build. |
| `SGLANG_DISAGG_STAGING_BUFFER` | `python/sglang/srt/environ.py` | Enables the heterogeneous-TP staging-buffer family and its overlap windows. |
| `SGLANG_STAGING_USE_TORCH` | `python/sglang/srt/disaggregation/common/staging_buffer.py` | Forces torch fallback for staging gather / scatter, so Triton staging kernels may disappear by design. |
| `SGLANG_VIT_ENABLE_CUDA_GRAPH` | `python/sglang/srt/environ.py` | Can intentionally disable vision `aux_stream` overlap. |
@@ -48,7 +48,7 @@ upstream overlap references as of this refresh.
| Llama4 shared branch vs routed branch overlap | shared expert branch plus routed MoE branch as adjacent windows | `python/sglang/srt/models/llama4.py` | shared expert on current stream, router + topk + routed experts on `alt_stream` | Use Llama4 as the first precedent for branch-level overlap in similar sparse models. |
| ExaoneMoE shared experts vs router experts overlap | shared expert output and router-expert output form a two-branch window | `python/sglang/srt/models/exaone_moe.py::forward_normal_dual_stream` | shared experts on current stream, router + routed experts on `alt_stream`, explicit join before combine | This is an existing dual-stream MoE overlap family. |
| Grok residual-MoE branch overlap | dense MLP and block-sparse MoE branches in parallel | `python/sglang/srt/models/grok.py::moe_with_rmoe` | dense MLP on current stream, MoE on `alt_stream`, fused dual residual RMSNorm around boundaries | Treat exposed Grok branch overlap as an existing pattern. |
| NSA dual-stream overlap | Q-proj, K-proj, RoPE, cache-store, quantization in tight two-stream windows | `python/sglang/srt/layers/attention/nsa/nsa_indexer.py` | Q / K projection split, RoPE split, cache-store vs quantization overlap | NSA already contains several dual-stream overlap precedents. |
| DSA dual-stream overlap | Q-proj, K-proj, RoPE, cache-store, quantization in tight two-stream windows | `python/sglang/srt/layers/attention/dsa/dsa_indexer.py` | Q / K projection split, RoPE split, cache-store vs quantization overlap | DSA already contains several dual-stream overlap precedents. |
| MoriEP async dispatch / combine comm stream | `MoriEP`<br>`_comm_stream`<br>`dispatch`<br>`combine`<br>`done_event` | `python/sglang/srt/layers/moe/token_dispatcher/moriep.py` | MoriEP can submit dispatch and combine onto a dedicated communication stream and synchronize only through events | Treat MoriEP comm / compute interleave as an existing MoE overlap family. |
| Generic `alt_stream` overlap families | `alt_stream` plus explicit `wait_stream` / `with torch.cuda.stream(...)` | `qwen2_moe.py`<br>`qwen3_moe.py`<br>`glm4_moe.py`<br>`bailing_moe.py`<br>`llada2.py`<br>`grok.py`<br>`olmo2.py`<br>`step3p5.py`<br>`longcat_flash.py`<br>`falcon_h1.py` | model-specific overlap on attention prep, MoE branches, or cache-store | Search these families before designing a new overlap scheme from scratch. |
@@ -530,16 +530,16 @@ FUSION_PATTERN_REGISTRY: Tuple[FusionPatternSpec, ...] = (
likely_share=0.5,
),
FusionPatternSpec(
pattern="NSA fused metadata copy for graph replay",
pattern="DSA fused metadata copy for graph replay",
candidate_path="python/sglang/jit_kernel/fused_metadata_copy.py",
active_keywords=(
"fused_metadata_copy",
"fused_metadata_copy_multi",
"fused_nsa_cache_seqlens",
"fused_dsa_cache_seqlens",
"fused_flashmla_metadata",
),
rationale_hint=(
"NSA replay metadata copies are already fused into one-kernel" " families."
"DSA replay metadata copies are already fused into one-kernel" " families."
),
min_share=0.02,
likely_share=0.2,
@@ -744,23 +744,23 @@ FUSION_PATTERN_REGISTRY: Tuple[FusionPatternSpec, ...] = (
likely_share=1.5,
),
FusionPatternSpec(
pattern="NSA fused top-k transform / page-table build",
candidate_path="python/sglang/srt/layers/attention/nsa_backend.py",
pattern="DSA fused top-k transform / page-table build",
candidate_path="python/sglang/srt/layers/attention/dsa_backend.py",
active_keywords=(
"fast_topk_transform_fused",
"fast_topk_transform_ragged_fused",
),
rationale_hint=(
"NSA top-k metadata preparation already has fused transform kernels."
"DSA top-k metadata preparation already has fused transform kernels."
),
min_share=0.05,
likely_share=0.3,
),
FusionPatternSpec(
pattern="NSA fused quantize + indexed K-cache store",
pattern="DSA fused quantize + indexed K-cache store",
candidate_path=(
"python/sglang/jit_kernel/fused_store_index_cache.py"
"<br>python/sglang/srt/layers/attention/nsa/nsa_indexer.py"
"<br>python/sglang/srt/layers/attention/dsa/dsa_indexer.py"
),
active_keywords=("fused_store_index_k_cache",),
split_groups=(
@@ -768,7 +768,7 @@ FUSION_PATTERN_REGISTRY: Tuple[FusionPatternSpec, ...] = (
("index_k", "cache", "store"),
),
rationale_hint=(
"NSA already has a fused quantize-and-indexed-store kernel family."
"DSA already has a fused quantize-and-indexed-store kernel family."
),
min_share=0.2,
likely_share=1.0,