[mem_cache][9/N] refactor: move DSAIndexerPoolHost to pool_host.dsa (#35306)

This commit is contained in:
Shuwen Wang
2026-08-21 15:59:15 +08:00
committed by GitHub
parent 8a123cbd0e
commit 8ff9c2b227
5 changed files with 489 additions and 444 deletions
@@ -15,12 +15,12 @@ from sglang.srt.mem_cache.hybrid_cache.hybrid_cache_controller import (
from sglang.srt.mem_cache.memory_pool_host import (
DeepSeekV4PagedHostPool,
DeepSeekV4StateHostPool,
DSAIndexerPoolHost,
HostPoolGroup,
LogicalHostPool,
PoolEntry,
)
from sglang.srt.mem_cache.pool_host.common import get_allocator_type
from sglang.srt.mem_cache.pool_host.dsa import DSAIndexerPoolHost
from sglang.srt.mem_cache.pool_host.mamba import MambaPoolHost
from sglang.srt.mem_cache.pool_host.mha import (
MHATokenToKOnlyPoolHost,
@@ -7,7 +7,6 @@ from typing import TYPE_CHECKING, Any, Callable, Optional
if TYPE_CHECKING:
from sglang.srt.mem_cache.hicache_storage import PoolName
from sglang.srt.mem_cache.pool_host.mla import MLATokenToKVPoolHost
import torch
@@ -18,9 +17,6 @@ from sglang.kernels.ops.kvcache.hicache import (
transfer_hicache_all_layer_mla_staged_lf_pf as jit_transfer_hicache_all_layer_mla_staged_lf_pf,
)
from sglang.kernels.ops.kvcache.hisparse import transfer_cache_dsv4_mla
from sglang.srt.mem_cache.memory_pool import (
DSATokenToKVPool,
)
from sglang.srt.utils import is_cuda, is_hip, is_mps, is_npu, is_xpu
_is_cuda = is_cuda()
@@ -1087,439 +1083,3 @@ class HostPoolGroup:
def set_from_flat_data_page(self, index: int, data_page) -> None:
return self.anchor_entry.host_pool.set_from_flat_data_page(index, data_page)
class DSAIndexerPoolHost(HostKVCache):
"""Host-side DSA index buffers only. Slot layout matches the anchor MLA host pool."""
device_pool: DSATokenToKVPool
def __init__(
self,
device_pool: DSATokenToKVPool,
anchor_host: MLATokenToKVPoolHost,
layout: str,
pin_memory: bool = True,
device: str = "cpu",
allocator_type: str = "default",
):
self.device_pool = device_pool
self.page_size = anchor_host.page_size
self.layout = layout
self.pin_memory = pin_memory
self.device = device
self.allocator = get_allocator_from_storage(allocator_type)
self.dtype = device_pool.store_dtype
self.start_layer = device_pool.start_layer
self.end_layer = device_pool.end_layer
self.target_layer_num = self._effective_host_layer_num()
self.mtp_draft_device_pools = anchor_host.mtp_draft_device_pools
self.layer_num = self.target_layer_num + len(self.mtp_draft_device_pools)
self.index_head_dim = device_pool.index_head_dim
self.indexer_quant_block_size = device_pool.quant_block_size
self.indexer_dtype = DSATokenToKVPool.index_k_with_scale_buffer_dtype
self.indexer_size_per_token = (
self.index_head_dim
+ self.index_head_dim // self.indexer_quant_block_size * 4
)
self.size = anchor_host.size
self.page_num = anchor_host.page_num
self.indexer_page_stride_size = (
self.indexer_size_per_token * self.page_size * self.indexer_dtype.itemsize
)
self.indexer_layout_dim = self.indexer_page_stride_size * self.layer_num
self.indexer_page_num = (self.size + self.page_size + 1) // self.page_size
self.size_per_token = (
self.indexer_size_per_token * self.layer_num * self.indexer_dtype.itemsize
)
buf_elem_size = self.page_num * self.layer_num * self.indexer_page_stride_size
requested_bytes = buf_elem_size * self.indexer_dtype.itemsize
available_bytes = host_memory_budget_bytes()
if requested_bytes > available_bytes:
raise ValueError(
f"Not enough host memory for DSA indexer hierarchical cache. "
f"Requesting {requested_bytes / 1e9:.2f} GB but only have "
f"{available_bytes / 1e9:.2f} GB free."
)
draft_layer_num = self.layer_num - self.target_layer_num
if draft_layer_num > 0:
logger.info(
"Allocating %.2f GB host memory for DSA indexer (layout=%s), "
"packed MTP layers: "
"target_layers=%d, draft_layers=%d, total_layers=%d.",
requested_bytes / 1e9,
layout,
self.target_layer_num,
draft_layer_num,
self.layer_num,
)
else:
logger.info(
"Allocating %.2f GB host memory for DSA indexer (layout=%s).",
requested_bytes / 1e9,
layout,
)
self.init_kv_buffer()
self.can_use_jit = False
self.can_use_write_back_jit = False
self._init_write_back_staging_buffers()
self.lock = threading.RLock()
self.clear()
def get_size_per_token(self):
return (
self.indexer_size_per_token * self.layer_num * self.indexer_dtype.itemsize
)
def get_ksize_per_token(self):
return self.get_size_per_token()
def init_kv_buffer(self):
alloc_func = ALLOC_MEMORY_FUNCS[self.device_pool.device]
device_pools = (self.device_pool, *self.mtp_draft_device_pools)
self.packed_device_index_buffers = [
buffer for pool in device_pools for buffer in pool.index_k_with_scale_buffer
]
self.index_k_device_ptrs = torch.tensor(
[x.data_ptr() for x in self.packed_device_index_buffers],
dtype=torch.uint64,
device=self.device_pool.device,
)
if self.layout == "layer_first":
self.index_k_with_scale_buffer = alloc_func(
(self.layer_num, self.indexer_page_num, self.indexer_page_stride_size),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
allocator=self.allocator,
)
self.index_k_data_refs = [
self.index_k_with_scale_buffer[i] for i in range(self.layer_num)
]
self.index_k_data_ptrs = torch.tensor(
[x.data_ptr() for x in self.index_k_data_refs],
dtype=torch.uint64,
device=self.device_pool.device,
)
elif self.layout in ["page_first", "page_first_direct"]:
self.index_k_with_scale_buffer = alloc_func(
(
self.indexer_page_num,
self.layer_num,
1,
self.indexer_page_stride_size,
),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
allocator=self.allocator,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
def _init_write_back_staging_buffers(self):
self.staging_buffer = None
if self.layout != "page_first" or (_is_npu or _is_xpu or _is_mps):
return
self.can_use_write_back_jit = _is_cuda and can_use_write_back_jit_kernel(
element_size=self.indexer_page_stride_size * self.indexer_dtype.itemsize,
)
staging_page_capacity = min(
self.indexer_page_num, _WRITE_BACK_STAGING_PAGE_CHUNK
)
self.staging_buffer = torch.empty(
(
staging_page_capacity,
self.layer_num,
1,
self.indexer_page_stride_size,
),
dtype=self.indexer_dtype,
device=self.device_pool.device,
)
def get_hybrid_pool_buffer(self):
return [self.index_k_with_scale_buffer]
def _get_indexer_page_indices(self, host_indices, device_indices):
if host_indices.numel() == 0:
return host_indices, device_indices
if host_indices.numel() % self.page_size != 0:
raise ValueError(
"Index buffer transfer expects page-aligned indices for DSA."
)
host_page_indices = (
host_indices.reshape(-1, self.page_size)[:, 0] // self.page_size
)
device_page_indices = (
device_indices.reshape(-1, self.page_size)[:, 0] // self.page_size
)
return host_page_indices, device_page_indices
def load_to_device_per_layer(
self,
device_pool,
host_indices,
device_indices,
layer_id,
io_backend,
*,
is_draft: bool = False,
):
if not is_draft and not self._is_device_layer_owned(device_pool, layer_id):
return
# MTP draft layers do not participate in CP layer sharding.
host_layer_id = layer_id if is_draft else self._host_layer_index(layer_id)
device_layer_id = 0 if is_draft else layer_id
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_per_layer_mla(
src=self.index_k_with_scale_buffer[host_layer_id],
dst=device_pool.index_k_with_scale_buffer[device_layer_id],
src_indices=host_page_indices,
dst_indices=device_page_indices,
item_size=self.indexer_page_stride_size,
)
elif self.layout == "page_first":
transfer_kv_per_layer_mla_pf_lf(
src=self.index_k_with_scale_buffer,
dst=device_pool.index_k_with_scale_buffer[device_layer_id],
src_indices=host_page_indices,
dst_indices=device_page_indices,
layer_id=host_layer_id,
item_size=self.indexer_page_stride_size,
src_layout_dim=self.indexer_layout_dim,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=[self.index_k_with_scale_buffer[host_layer_id]],
dst_layers=[device_pool.index_k_with_scale_buffer[device_layer_id]],
src_indices=host_page_indices,
dst_indices=device_page_indices,
page_size=1,
)
elif self.layout == "page_first_direct":
transfer_kv_per_layer_direct_pf_lf(
src_ptrs=[self.index_k_with_scale_buffer],
dst_ptrs=[device_pool.index_k_with_scale_buffer[device_layer_id]],
src_indices=host_page_indices,
dst_indices=device_page_indices,
layer_id=host_layer_id,
page_size=1,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def _backup_from_device_per_layer(
self,
device_pool,
host_indices,
device_indices,
layer_id,
io_backend,
*,
is_draft: bool = False,
):
# MTP draft layers do not participate in CP layer sharding.
host_layer_id = layer_id if is_draft else self._host_layer_index(layer_id)
device_layer_id = 0 if is_draft else layer_id
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_per_layer_mla(
src=device_pool.index_k_with_scale_buffer[device_layer_id],
dst=self.index_k_with_scale_buffer[host_layer_id],
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
)
elif self.layout == "page_first":
raise ValueError(
"Layer-sharded DSA indexer HiCache backup with page_first "
"layout is not supported without a per-layer LF->PF kernel."
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=[device_pool.index_k_with_scale_buffer[device_layer_id]],
dst_layers=[self.index_k_with_scale_buffer[host_layer_id]],
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
else:
raise ValueError(
"Layer-sharded direct DSA indexer backup only supports "
f"layer_first layout, got {self.layout}"
)
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def backup_from_device_all_layer(
self, device_pool, host_indices, device_indices, io_backend
):
if self._is_device_layer_sharded(device_pool):
for layer_id in self._owned_device_layer_ids(device_pool):
self._backup_from_device_per_layer(
device_pool, host_indices, device_indices, layer_id, io_backend
)
for draft_layer_id, draft_device_pool in enumerate(
self.mtp_draft_device_pools
):
self._backup_from_device_per_layer(
draft_device_pool,
host_indices,
device_indices,
self.device_pool.layer_num + draft_layer_id,
io_backend,
is_draft=True,
)
return
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_all_layer_mla(
src_layers=self.index_k_device_ptrs,
dst_layers=self.index_k_data_ptrs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
num_layers=self.layer_num,
)
elif self.layout == "page_first":
if self.can_use_write_back_jit:
jit_transfer_hicache_all_layer_mla_staged_lf_pf(
ptr_src=self.index_k_device_ptrs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
staging=self.staging_buffer,
dst=self.index_k_with_scale_buffer,
page_size=1,
element_size=self.indexer_page_stride_size,
)
else:
transfer_kv_all_layer_mla_lf_pf(
src_layers=self.index_k_device_ptrs,
dst=self.index_k_with_scale_buffer,
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
dst_layout_dim=self.indexer_layout_dim,
num_layers=self.layer_num,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=self.packed_device_index_buffers,
dst_layers=self.index_k_data_refs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
elif self.layout == "page_first_direct":
transfer_kv_all_layer_direct_lf_pf(
src_ptrs=self.packed_device_index_buffers,
dst_ptrs=[self.index_k_with_scale_buffer],
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def get_data_page(self, index, flat: bool = True) -> torch.Tensor:
page_idx = int(index) // self.page_size
if self.layout == "layer_first":
data_page = self.index_k_with_scale_buffer[:, page_idx : page_idx + 1, :]
elif self.layout in ["page_first", "page_first_direct"]:
data_page = self.index_k_with_scale_buffer[page_idx : page_idx + 1, :, :, :]
else:
raise ValueError(f"Unsupported layout: {self.layout}")
if flat:
data_page = data_page.flatten()
return data_page
def get_dummy_flat_data_page(self) -> torch.Tensor:
return torch.zeros(
(self.layer_num, self.indexer_page_stride_size),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
).flatten()
def set_from_flat_data_page(self, index: int, data_page: torch.Tensor) -> None:
page_idx = int(index) // self.page_size
if self.layout == "layer_first":
self.index_k_with_scale_buffer[:, page_idx : page_idx + 1, :] = (
data_page.reshape(
self.layer_num,
1,
self.indexer_page_stride_size,
)
)
elif self.layout in ["page_first", "page_first_direct"]:
self.index_k_with_scale_buffer[page_idx : page_idx + 1, :, :, :] = (
data_page.reshape(
1,
self.layer_num,
1,
self.indexer_page_stride_size,
)
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
def get_page_buffer_meta(self, indices):
"""Meta data for zero-copy storage I/O."""
assert len(indices) % self.page_size == 0
if self.layout not in ["page_first", "page_first_direct"]:
raise ValueError(f"Unsupported layout: {self.layout}")
ptr_list = []
indices = indices.tolist()
page_stride_bytes = (
self.layer_num * self.indexer_page_stride_size * self.indexer_dtype.itemsize
)
base_ptr = self.index_k_with_scale_buffer.data_ptr()
for i in range(0, len(indices), self.page_size):
page_index = int(indices[i]) // self.page_size
ptr_list.append(base_ptr + page_index * page_stride_bytes)
return ptr_list, [page_stride_bytes] * len(ptr_list)
def is_stride_page_aligned(self, page_size_bytes: int = 4096) -> bool:
if self.layout not in ["page_first", "page_first_direct"]:
return False
page_stride_bytes = (
self.layer_num * self.indexer_page_stride_size * self.indexer_dtype.itemsize
)
return (
self.index_k_with_scale_buffer.data_ptr() % page_size_bytes == 0
and page_stride_bytes % page_size_bytes == 0
)
@@ -0,0 +1,482 @@
from __future__ import annotations
import logging
import threading
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from sglang.srt.mem_cache.pool_host.mla import MLATokenToKVPoolHost
import torch
from sglang.kernels.ops.kvcache.hicache import (
can_use_write_back_jit_kernel,
)
from sglang.kernels.ops.kvcache.hicache import (
transfer_hicache_all_layer_mla_staged_lf_pf as jit_transfer_hicache_all_layer_mla_staged_lf_pf,
)
from sglang.srt.mem_cache.memory_pool import DSATokenToKVPool
from sglang.srt.mem_cache.pool_host.base import (
_WRITE_BACK_STAGING_PAGE_CHUNK,
HostKVCache,
host_memory_budget_bytes,
)
from sglang.srt.mem_cache.pool_host.common import (
ALLOC_MEMORY_FUNCS,
get_allocator_from_storage,
)
from sglang.srt.utils import is_cuda, is_hip, is_mps, is_npu, is_xpu
_is_cuda = is_cuda()
_is_hip = is_hip()
_is_npu = is_npu()
_is_xpu = is_xpu()
_is_mps = is_mps()
if _is_cuda or _is_hip:
from sgl_kernel.kvcacheio import (
transfer_kv_all_layer_direct_lf_pf,
transfer_kv_all_layer_mla,
transfer_kv_all_layer_mla_lf_pf,
transfer_kv_direct,
transfer_kv_per_layer_direct_pf_lf,
transfer_kv_per_layer_mla,
transfer_kv_per_layer_mla_pf_lf,
)
logger = logging.getLogger(__name__)
class DSAIndexerPoolHost(HostKVCache):
"""Host-side DSA index buffers only. Slot layout matches the anchor MLA host pool."""
device_pool: DSATokenToKVPool
def __init__(
self,
device_pool: DSATokenToKVPool,
anchor_host: MLATokenToKVPoolHost,
layout: str,
pin_memory: bool = True,
device: str = "cpu",
allocator_type: str = "default",
):
self.device_pool = device_pool
self.page_size = anchor_host.page_size
self.layout = layout
self.pin_memory = pin_memory
self.device = device
self.allocator = get_allocator_from_storage(allocator_type)
self.dtype = device_pool.store_dtype
self.start_layer = device_pool.start_layer
self.end_layer = device_pool.end_layer
self.target_layer_num = self._effective_host_layer_num()
self.mtp_draft_device_pools = anchor_host.mtp_draft_device_pools
self.layer_num = self.target_layer_num + len(self.mtp_draft_device_pools)
self.index_head_dim = device_pool.index_head_dim
self.indexer_quant_block_size = device_pool.quant_block_size
self.indexer_dtype = DSATokenToKVPool.index_k_with_scale_buffer_dtype
self.indexer_size_per_token = (
self.index_head_dim
+ self.index_head_dim // self.indexer_quant_block_size * 4
)
self.size = anchor_host.size
self.page_num = anchor_host.page_num
self.indexer_page_stride_size = (
self.indexer_size_per_token * self.page_size * self.indexer_dtype.itemsize
)
self.indexer_layout_dim = self.indexer_page_stride_size * self.layer_num
self.indexer_page_num = (self.size + self.page_size + 1) // self.page_size
self.size_per_token = (
self.indexer_size_per_token * self.layer_num * self.indexer_dtype.itemsize
)
buf_elem_size = self.page_num * self.layer_num * self.indexer_page_stride_size
requested_bytes = buf_elem_size * self.indexer_dtype.itemsize
available_bytes = host_memory_budget_bytes()
if requested_bytes > available_bytes:
raise ValueError(
f"Not enough host memory for DSA indexer hierarchical cache. "
f"Requesting {requested_bytes / 1e9:.2f} GB but only have "
f"{available_bytes / 1e9:.2f} GB free."
)
draft_layer_num = self.layer_num - self.target_layer_num
if draft_layer_num > 0:
logger.info(
"Allocating %.2f GB host memory for DSA indexer (layout=%s), "
"packed MTP layers: "
"target_layers=%d, draft_layers=%d, total_layers=%d.",
requested_bytes / 1e9,
layout,
self.target_layer_num,
draft_layer_num,
self.layer_num,
)
else:
logger.info(
"Allocating %.2f GB host memory for DSA indexer (layout=%s).",
requested_bytes / 1e9,
layout,
)
self.init_kv_buffer()
self.can_use_jit = False
self.can_use_write_back_jit = False
self._init_write_back_staging_buffers()
self.lock = threading.RLock()
self.clear()
def get_size_per_token(self):
return (
self.indexer_size_per_token * self.layer_num * self.indexer_dtype.itemsize
)
def get_ksize_per_token(self):
return self.get_size_per_token()
def init_kv_buffer(self):
alloc_func = ALLOC_MEMORY_FUNCS[self.device_pool.device]
device_pools = (self.device_pool, *self.mtp_draft_device_pools)
self.packed_device_index_buffers = [
buffer for pool in device_pools for buffer in pool.index_k_with_scale_buffer
]
self.index_k_device_ptrs = torch.tensor(
[x.data_ptr() for x in self.packed_device_index_buffers],
dtype=torch.uint64,
device=self.device_pool.device,
)
if self.layout == "layer_first":
self.index_k_with_scale_buffer = alloc_func(
(self.layer_num, self.indexer_page_num, self.indexer_page_stride_size),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
allocator=self.allocator,
)
self.index_k_data_refs = [
self.index_k_with_scale_buffer[i] for i in range(self.layer_num)
]
self.index_k_data_ptrs = torch.tensor(
[x.data_ptr() for x in self.index_k_data_refs],
dtype=torch.uint64,
device=self.device_pool.device,
)
elif self.layout in ["page_first", "page_first_direct"]:
self.index_k_with_scale_buffer = alloc_func(
(
self.indexer_page_num,
self.layer_num,
1,
self.indexer_page_stride_size,
),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
allocator=self.allocator,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
def _init_write_back_staging_buffers(self):
self.staging_buffer = None
if self.layout != "page_first" or (_is_npu or _is_xpu or _is_mps):
return
self.can_use_write_back_jit = _is_cuda and can_use_write_back_jit_kernel(
element_size=self.indexer_page_stride_size * self.indexer_dtype.itemsize,
)
staging_page_capacity = min(
self.indexer_page_num, _WRITE_BACK_STAGING_PAGE_CHUNK
)
self.staging_buffer = torch.empty(
(
staging_page_capacity,
self.layer_num,
1,
self.indexer_page_stride_size,
),
dtype=self.indexer_dtype,
device=self.device_pool.device,
)
def get_hybrid_pool_buffer(self):
return [self.index_k_with_scale_buffer]
def _get_indexer_page_indices(self, host_indices, device_indices):
if host_indices.numel() == 0:
return host_indices, device_indices
if host_indices.numel() % self.page_size != 0:
raise ValueError(
"Index buffer transfer expects page-aligned indices for DSA."
)
host_page_indices = (
host_indices.reshape(-1, self.page_size)[:, 0] // self.page_size
)
device_page_indices = (
device_indices.reshape(-1, self.page_size)[:, 0] // self.page_size
)
return host_page_indices, device_page_indices
def load_to_device_per_layer(
self,
device_pool,
host_indices,
device_indices,
layer_id,
io_backend,
*,
is_draft: bool = False,
):
if not is_draft and not self._is_device_layer_owned(device_pool, layer_id):
return
# MTP draft layers do not participate in CP layer sharding.
host_layer_id = layer_id if is_draft else self._host_layer_index(layer_id)
device_layer_id = 0 if is_draft else layer_id
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_per_layer_mla(
src=self.index_k_with_scale_buffer[host_layer_id],
dst=device_pool.index_k_with_scale_buffer[device_layer_id],
src_indices=host_page_indices,
dst_indices=device_page_indices,
item_size=self.indexer_page_stride_size,
)
elif self.layout == "page_first":
transfer_kv_per_layer_mla_pf_lf(
src=self.index_k_with_scale_buffer,
dst=device_pool.index_k_with_scale_buffer[device_layer_id],
src_indices=host_page_indices,
dst_indices=device_page_indices,
layer_id=host_layer_id,
item_size=self.indexer_page_stride_size,
src_layout_dim=self.indexer_layout_dim,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=[self.index_k_with_scale_buffer[host_layer_id]],
dst_layers=[device_pool.index_k_with_scale_buffer[device_layer_id]],
src_indices=host_page_indices,
dst_indices=device_page_indices,
page_size=1,
)
elif self.layout == "page_first_direct":
transfer_kv_per_layer_direct_pf_lf(
src_ptrs=[self.index_k_with_scale_buffer],
dst_ptrs=[device_pool.index_k_with_scale_buffer[device_layer_id]],
src_indices=host_page_indices,
dst_indices=device_page_indices,
layer_id=host_layer_id,
page_size=1,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def _backup_from_device_per_layer(
self,
device_pool,
host_indices,
device_indices,
layer_id,
io_backend,
*,
is_draft: bool = False,
):
# MTP draft layers do not participate in CP layer sharding.
host_layer_id = layer_id if is_draft else self._host_layer_index(layer_id)
device_layer_id = 0 if is_draft else layer_id
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_per_layer_mla(
src=device_pool.index_k_with_scale_buffer[device_layer_id],
dst=self.index_k_with_scale_buffer[host_layer_id],
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
)
elif self.layout == "page_first":
raise ValueError(
"Layer-sharded DSA indexer HiCache backup with page_first "
"layout is not supported without a per-layer LF->PF kernel."
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=[device_pool.index_k_with_scale_buffer[device_layer_id]],
dst_layers=[self.index_k_with_scale_buffer[host_layer_id]],
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
else:
raise ValueError(
"Layer-sharded direct DSA indexer backup only supports "
f"layer_first layout, got {self.layout}"
)
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def backup_from_device_all_layer(
self, device_pool, host_indices, device_indices, io_backend
):
if self._is_device_layer_sharded(device_pool):
for layer_id in self._owned_device_layer_ids(device_pool):
self._backup_from_device_per_layer(
device_pool, host_indices, device_indices, layer_id, io_backend
)
for draft_layer_id, draft_device_pool in enumerate(
self.mtp_draft_device_pools
):
self._backup_from_device_per_layer(
draft_device_pool,
host_indices,
device_indices,
self.device_pool.layer_num + draft_layer_id,
io_backend,
is_draft=True,
)
return
host_page_indices, device_page_indices = self._get_indexer_page_indices(
host_indices, device_indices
)
use_kernel = io_backend == "kernel" and self.indexer_page_stride_size % 8 == 0
if use_kernel:
if self.layout == "layer_first":
transfer_kv_all_layer_mla(
src_layers=self.index_k_device_ptrs,
dst_layers=self.index_k_data_ptrs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
num_layers=self.layer_num,
)
elif self.layout == "page_first":
if self.can_use_write_back_jit:
jit_transfer_hicache_all_layer_mla_staged_lf_pf(
ptr_src=self.index_k_device_ptrs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
staging=self.staging_buffer,
dst=self.index_k_with_scale_buffer,
page_size=1,
element_size=self.indexer_page_stride_size,
)
else:
transfer_kv_all_layer_mla_lf_pf(
src_layers=self.index_k_device_ptrs,
dst=self.index_k_with_scale_buffer,
src_indices=device_page_indices,
dst_indices=host_page_indices,
item_size=self.indexer_page_stride_size,
dst_layout_dim=self.indexer_layout_dim,
num_layers=self.layer_num,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
elif io_backend == "direct":
if self.layout == "layer_first":
transfer_kv_direct(
src_layers=self.packed_device_index_buffers,
dst_layers=self.index_k_data_refs,
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
elif self.layout == "page_first_direct":
transfer_kv_all_layer_direct_lf_pf(
src_ptrs=self.packed_device_index_buffers,
dst_ptrs=[self.index_k_with_scale_buffer],
src_indices=device_page_indices,
dst_indices=host_page_indices,
page_size=1,
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
else:
raise ValueError(f"Unsupported IO backend: {io_backend}")
def get_data_page(self, index, flat: bool = True) -> torch.Tensor:
page_idx = int(index) // self.page_size
if self.layout == "layer_first":
data_page = self.index_k_with_scale_buffer[:, page_idx : page_idx + 1, :]
elif self.layout in ["page_first", "page_first_direct"]:
data_page = self.index_k_with_scale_buffer[page_idx : page_idx + 1, :, :, :]
else:
raise ValueError(f"Unsupported layout: {self.layout}")
if flat:
data_page = data_page.flatten()
return data_page
def get_dummy_flat_data_page(self) -> torch.Tensor:
return torch.zeros(
(self.layer_num, self.indexer_page_stride_size),
dtype=self.indexer_dtype,
device=self.device,
pin_memory=self.pin_memory,
).flatten()
def set_from_flat_data_page(self, index: int, data_page: torch.Tensor) -> None:
page_idx = int(index) // self.page_size
if self.layout == "layer_first":
self.index_k_with_scale_buffer[:, page_idx : page_idx + 1, :] = (
data_page.reshape(
self.layer_num,
1,
self.indexer_page_stride_size,
)
)
elif self.layout in ["page_first", "page_first_direct"]:
self.index_k_with_scale_buffer[page_idx : page_idx + 1, :, :, :] = (
data_page.reshape(
1,
self.layer_num,
1,
self.indexer_page_stride_size,
)
)
else:
raise ValueError(f"Unsupported layout: {self.layout}")
def get_page_buffer_meta(self, indices):
"""Meta data for zero-copy storage I/O."""
assert len(indices) % self.page_size == 0
if self.layout not in ["page_first", "page_first_direct"]:
raise ValueError(f"Unsupported layout: {self.layout}")
ptr_list = []
indices = indices.tolist()
page_stride_bytes = (
self.layer_num * self.indexer_page_stride_size * self.indexer_dtype.itemsize
)
base_ptr = self.index_k_with_scale_buffer.data_ptr()
for i in range(0, len(indices), self.page_size):
page_index = int(indices[i]) // self.page_size
ptr_list.append(base_ptr + page_index * page_stride_bytes)
return ptr_list, [page_stride_bytes] * len(ptr_list)
def is_stride_page_aligned(self, page_size_bytes: int = 4096) -> bool:
if self.layout not in ["page_first", "page_first_direct"]:
return False
page_stride_bytes = (
self.layer_num * self.indexer_page_stride_size * self.indexer_dtype.itemsize
)
return (
self.index_k_with_scale_buffer.data_ptr() % page_size_bytes == 0
and page_stride_bytes % page_size_bytes == 0
)