vllm/vllm/v1/core/encoder_cache_manager.py
Roger Wang 70755e819e
[V1][Core] Autotune encoder cache budget (#11895)
Signed-off-by: Roger Wang <ywang@roblox.com>
2025-01-15 11:29:00 -08:00

125 lines
4.2 KiB
Python

from typing import TYPE_CHECKING, Dict, List, Set, Tuple
from vllm.logger import init_logger
from vllm.multimodal import MULTIMODAL_REGISTRY
from vllm.v1.request import Request
if TYPE_CHECKING:
from vllm.config import ModelConfig, SchedulerConfig
logger = init_logger(__name__)
class EncoderCacheManager:
def __init__(self, cache_size: int):
self.cache_size = cache_size
self.num_free_slots = cache_size
# req_id -> cached input ids
self.cached: Dict[str, Set[int]] = {}
# List of [req_id, input_id]
self.freed: List[Tuple[str, int]] = []
def has_cache(self, request: Request, input_id: int) -> bool:
req_id = request.request_id
return req_id in self.cached and input_id in self.cached[req_id]
def can_allocate(self, request: Request, input_id: int) -> bool:
num_tokens = request.get_num_encoder_tokens(input_id)
return num_tokens <= self.num_free_slots
def allocate(self, request: Request, input_id: int) -> None:
req_id = request.request_id
if req_id not in self.cached:
self.cached[req_id] = set()
self.cached[req_id].add(input_id)
self.num_free_slots -= request.get_num_encoder_tokens(input_id)
def get_cached_input_ids(self, request: Request) -> Set[int]:
return self.cached.get(request.request_id, set())
def free(self, request: Request, input_id: int) -> None:
req_id = request.request_id
if req_id not in self.cached:
return
self.cached[req_id].discard(input_id)
if len(self.cached[req_id]) == 0:
del self.cached[req_id]
self.num_free_slots += request.get_num_encoder_tokens(input_id)
self.freed.append((req_id, input_id))
def get_freed_ids(self) -> List[Tuple[str, int]]:
freed = self.freed
self.freed = []
return freed
def compute_encoder_budget(
model_config: "ModelConfig",
scheduler_config: "SchedulerConfig",
) -> Tuple[int, int]:
"""Compute the encoder cache budget based on the model and scheduler
configurations.
Args:
model_config: Model configuration.
scheduler_config: Scheduler configuration.
Returns:
- Compute budget for encoder execution, in unit of number of tokens
in the input sequence.
- Space budget for encoder cache size, in unit of number of tokens
in the input sequence.
"""
if not model_config.is_multimodal_model:
return 0, 0
# TODO: handle encoder-decoder models once we support them.
(
encoder_compute_budget,
encoder_cache_size,
) = _compute_encoder_budget_multimodal(model_config, scheduler_config)
return encoder_compute_budget, encoder_cache_size
def _compute_encoder_budget_multimodal(
model_config: "ModelConfig",
scheduler_config: "SchedulerConfig",
) -> Tuple[int, int]:
"""Compute the encoder cache budget based on the model and scheduler
configurations for a multimodal model.
Args:
model_config: Model configuration.
scheduler_config: Scheduler configuration.
Returns:
- Compute budget for encoder execution, in unit of number of tokens
in the input sequence.
- Space budget for encoder cache size, in unit of number of tokens
in the input sequence.
"""
max_tokens_by_modality_dict = MULTIMODAL_REGISTRY.get_max_tokens_per_item_by_nonzero_modality( # noqa: E501
model_config)
if not max_tokens_by_modality_dict:
logger.warning(
"All non-text modalities supported by the model have been "
"explicitly disabled via limit_mm_per_prompt. Encoder cache will "
"not be initialized.")
return 0, 0
_, max_tokens_per_mm_item = max(max_tokens_by_modality_dict.items(),
key=lambda item: item[1])
encoder_compute_budget = max(scheduler_config.max_num_encoder_input_tokens,
max_tokens_per_mm_item)
encoder_cache_size = max(scheduler_config.encoder_cache_size,
max_tokens_per_mm_item)
return encoder_compute_budget, encoder_cache_size