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https://git.datalinker.icu/vllm-project/vllm.git
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Currently, when requests are cancelled while executing their final step, "completion" is handled based on normal stop processing (e.g. length or stop token), so the abort has no effect. This is typically not a problem, but when a kv connector is involved it thinks the request completed successfully rather than being aborted. This is problematic for disaggregated prefill which will free kv cache blocks if the request was aborted but not if it completed successfully—since the cancelled request will never be sent to the decode side, kv cache blocks remain pinned until the fall-back timeout expires. The problem is exacerbated when many requests are cancelled and/or there are large prefills whose forward pass takes a long time (since the window is bigger). This PR fixes the problem by processing pending aborts immediately prior to processing model output each step; we process only aborts, not new requests, since it's preferable for latency to process model outputs before new incoming requests. Fixes #26400. Signed-off-by: Nick Hill <nhill@redhat.com>
1453 lines
57 KiB
Python
1453 lines
57 KiB
Python
# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
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import os
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import queue
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import signal
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import threading
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import time
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from collections import deque
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from collections.abc import Callable, Generator
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from concurrent.futures import Future
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from contextlib import ExitStack, contextmanager
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from inspect import isclass, signature
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from logging import DEBUG
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from typing import Any, TypeVar, cast
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import msgspec
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import zmq
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from vllm.config import ParallelConfig, VllmConfig
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from vllm.distributed import stateless_destroy_torch_distributed_process_group
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from vllm.envs import enable_envs_cache
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from vllm.logger import init_logger
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from vllm.logging_utils.dump_input import dump_engine_exception
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from vllm.lora.request import LoRARequest
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from vllm.multimodal import MULTIMODAL_REGISTRY
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from vllm.multimodal.cache import engine_receiver_cache_from_config
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from vllm.tasks import POOLING_TASKS, SupportedTask
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from vllm.transformers_utils.config import maybe_register_config_serialize_by_value
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from vllm.utils.gc_utils import (
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freeze_gc_heap,
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maybe_attach_gc_debug_callback,
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)
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from vllm.utils.hashing import get_hash_fn_by_name
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from vllm.utils.network_utils import make_zmq_socket
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from vllm.utils.system_utils import decorate_logs, set_process_title
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from vllm.v1.core.kv_cache_utils import (
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BlockHash,
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generate_scheduler_kv_cache_config,
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get_kv_cache_configs,
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get_request_block_hasher,
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init_none_hash,
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)
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from vllm.v1.core.sched.interface import SchedulerInterface
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from vllm.v1.core.sched.output import SchedulerOutput
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from vllm.v1.engine import (
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EngineCoreOutputs,
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EngineCoreRequest,
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EngineCoreRequestType,
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ReconfigureDistributedRequest,
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ReconfigureRankType,
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UtilityOutput,
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UtilityResult,
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)
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from vllm.v1.engine.utils import (
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EngineHandshakeMetadata,
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EngineZmqAddresses,
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get_device_indices,
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)
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from vllm.v1.executor import Executor
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from vllm.v1.kv_cache_interface import KVCacheConfig
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from vllm.v1.metrics.stats import SchedulerStats
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from vllm.v1.outputs import ModelRunnerOutput
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from vllm.v1.request import Request, RequestStatus
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from vllm.v1.serial_utils import MsgpackDecoder, MsgpackEncoder
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from vllm.v1.structured_output import StructuredOutputManager
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from vllm.version import __version__ as VLLM_VERSION
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logger = init_logger(__name__)
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POLLING_TIMEOUT_S = 2.5
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HANDSHAKE_TIMEOUT_MINS = 5
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_R = TypeVar("_R") # Return type for collective_rpc
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class EngineCore:
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"""Inner loop of vLLM's Engine."""
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def __init__(
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self,
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vllm_config: VllmConfig,
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executor_class: type[Executor],
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log_stats: bool,
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executor_fail_callback: Callable | None = None,
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):
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# plugins need to be loaded at the engine/scheduler level too
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from vllm.plugins import load_general_plugins
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load_general_plugins()
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self.vllm_config = vllm_config
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if vllm_config.parallel_config.data_parallel_rank == 0:
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logger.info(
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"Initializing a V1 LLM engine (v%s) with config: %s",
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VLLM_VERSION,
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vllm_config,
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)
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self.log_stats = log_stats
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# Setup Model.
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self.model_executor = executor_class(vllm_config)
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if executor_fail_callback is not None:
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self.model_executor.register_failure_callback(executor_fail_callback)
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self.available_gpu_memory_for_kv_cache = -1
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# Setup KV Caches and update CacheConfig after profiling.
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num_gpu_blocks, num_cpu_blocks, kv_cache_config = self._initialize_kv_caches(
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vllm_config
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)
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vllm_config.cache_config.num_gpu_blocks = num_gpu_blocks
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vllm_config.cache_config.num_cpu_blocks = num_cpu_blocks
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self.collective_rpc("initialize_cache", args=(num_gpu_blocks, num_cpu_blocks))
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self.structured_output_manager = StructuredOutputManager(vllm_config)
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# Setup scheduler.
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Scheduler = vllm_config.scheduler_config.get_scheduler_cls()
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if len(kv_cache_config.kv_cache_groups) == 0: # noqa: SIM102
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# Encoder models without KV cache don't support
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# chunked prefill. But do SSM models?
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if vllm_config.scheduler_config.enable_chunked_prefill:
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logger.warning("Disabling chunked prefill for model without KVCache")
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vllm_config.scheduler_config.enable_chunked_prefill = False
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scheduler_block_size = (
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vllm_config.cache_config.block_size
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* vllm_config.parallel_config.decode_context_parallel_size
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* vllm_config.parallel_config.prefill_context_parallel_size
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)
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self.scheduler: SchedulerInterface = Scheduler(
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vllm_config=vllm_config,
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kv_cache_config=kv_cache_config,
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structured_output_manager=self.structured_output_manager,
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include_finished_set=vllm_config.parallel_config.data_parallel_size > 1,
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log_stats=self.log_stats,
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block_size=scheduler_block_size,
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)
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self.use_spec_decode = vllm_config.speculative_config is not None
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if self.scheduler.connector is not None: # type: ignore
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self.model_executor.init_kv_output_aggregator(self.scheduler.connector) # type: ignore
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self.mm_registry = mm_registry = MULTIMODAL_REGISTRY
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self.mm_receiver_cache = engine_receiver_cache_from_config(
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vllm_config, mm_registry
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)
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# If a KV connector is initialized for scheduler, we want to collect
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# handshake metadata from all workers so the connector in the scheduler
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# will have the full context
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kv_connector = self.scheduler.get_kv_connector()
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if kv_connector is not None:
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# Collect and store KV connector xfer metadata from workers
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# (after KV cache registration)
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xfer_handshake_metadata = (
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self.model_executor.get_kv_connector_handshake_metadata()
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)
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if xfer_handshake_metadata:
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# xfer_handshake_metadata is list of dicts from workers
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# Each dict already has structure {tp_rank: metadata}
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# Merge all worker dicts into a single dict
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content: dict[int, Any] = {}
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for worker_dict in xfer_handshake_metadata:
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if worker_dict is not None:
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content.update(worker_dict)
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kv_connector.set_xfer_handshake_metadata(content)
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# Setup batch queue for pipeline parallelism.
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# Batch queue for scheduled batches. This enables us to asynchronously
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# schedule and execute batches, and is required by pipeline parallelism
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# to eliminate pipeline bubbles.
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self.batch_queue_size = self.model_executor.max_concurrent_batches
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self.batch_queue: (
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deque[tuple[Future[ModelRunnerOutput], SchedulerOutput]] | None
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) = None
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if self.batch_queue_size > 1:
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logger.info("Batch queue is enabled with size %d", self.batch_queue_size)
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self.batch_queue = deque(maxlen=self.batch_queue_size)
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self.is_ec_producer = (
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vllm_config.ec_transfer_config is not None
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and vllm_config.ec_transfer_config.is_ec_producer
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)
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self.is_pooling_model = vllm_config.model_config.runner_type == "pooling"
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self.request_block_hasher: Callable[[Request], list[BlockHash]] | None = None
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if vllm_config.cache_config.enable_prefix_caching or kv_connector is not None:
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caching_hash_fn = get_hash_fn_by_name(
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vllm_config.cache_config.prefix_caching_hash_algo
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)
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init_none_hash(caching_hash_fn)
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self.request_block_hasher = get_request_block_hasher(
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scheduler_block_size, caching_hash_fn
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)
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self.step_fn = (
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self.step if self.batch_queue is None else self.step_with_batch_queue
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)
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self.async_scheduling = vllm_config.scheduler_config.async_scheduling
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self.aborts_queue = queue.Queue[list[str]]()
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# Mark the startup heap as static so that it's ignored by GC.
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# Reduces pause times of oldest generation collections.
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freeze_gc_heap()
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# If enable, attach GC debugger after static variable freeze.
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maybe_attach_gc_debug_callback()
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def _initialize_kv_caches(
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self, vllm_config: VllmConfig
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) -> tuple[int, int, KVCacheConfig]:
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start = time.time()
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# Get all kv cache needed by the model
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kv_cache_specs = self.model_executor.get_kv_cache_specs()
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has_kv_cache = any(kv_cache_spec for kv_cache_spec in kv_cache_specs)
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if has_kv_cache:
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if os.environ.get("VLLM_ELASTIC_EP_SCALE_UP_LAUNCH") == "1":
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dp_group = getattr(self, "dp_group", None)
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assert dp_group is not None
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self.available_gpu_memory_for_kv_cache = (
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ParallelConfig.sync_kv_cache_memory_size(dp_group, -1)
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)
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available_gpu_memory = [self.available_gpu_memory_for_kv_cache] * len(
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kv_cache_specs
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)
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else:
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# Profiles the peak memory usage of the model to determine how
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# much memory can be allocated for kv cache.
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available_gpu_memory = self.model_executor.determine_available_memory()
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self.available_gpu_memory_for_kv_cache = available_gpu_memory[0]
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else:
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# Attention free models don't need memory for kv cache
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available_gpu_memory = [0] * len(kv_cache_specs)
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assert len(kv_cache_specs) == len(available_gpu_memory)
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kv_cache_configs = get_kv_cache_configs(
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vllm_config, kv_cache_specs, available_gpu_memory
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)
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scheduler_kv_cache_config = generate_scheduler_kv_cache_config(kv_cache_configs)
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num_gpu_blocks = scheduler_kv_cache_config.num_blocks
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num_cpu_blocks = 0
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# Initialize kv cache and warmup the execution
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self.model_executor.initialize_from_config(kv_cache_configs)
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elapsed = time.time() - start
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logger.info_once(
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"init engine (profile, create kv cache, warmup model) took %.2f seconds",
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elapsed,
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scope="local",
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)
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return num_gpu_blocks, num_cpu_blocks, scheduler_kv_cache_config
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def get_supported_tasks(self) -> tuple[SupportedTask, ...]:
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return self.model_executor.supported_tasks
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def add_request(self, request: Request, request_wave: int = 0):
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"""Add request to the scheduler.
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`request_wave`: indicate which wave of requests this is expected to
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belong to in DP case
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"""
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# Validate the request_id type.
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if not isinstance(request.request_id, str):
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raise TypeError(
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f"request_id must be a string, got {type(request.request_id)}"
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)
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if pooling_params := request.pooling_params:
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supported_pooling_tasks = [
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task for task in self.get_supported_tasks() if task in POOLING_TASKS
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]
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if pooling_params.task not in supported_pooling_tasks:
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raise ValueError(
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f"Unsupported task: {pooling_params.task!r} "
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f"Supported tasks: {supported_pooling_tasks}"
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)
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if request.kv_transfer_params is not None and (
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not self.scheduler.get_kv_connector()
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):
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logger.warning(
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"Got kv_transfer_params, but no KVConnector found. "
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"Disabling KVTransfer for this request."
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)
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self.scheduler.add_request(request)
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def abort_requests(self, request_ids: list[str]):
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"""Abort requests from the scheduler."""
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# TODO: The scheduler doesn't really need to know the
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# specific finish reason, TBD whether we propagate that
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# (i.e. client-aborted vs stop criteria met).
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self.scheduler.finish_requests(request_ids, RequestStatus.FINISHED_ABORTED)
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@contextmanager
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def log_error_detail(self, scheduler_output: SchedulerOutput):
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"""Execute the model and log detailed info on failure."""
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try:
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yield
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except Exception as err:
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# We do not want to catch BaseException here since we're only
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# interested in dumping info when the exception is due to an
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# error from execute_model itself.
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# NOTE: This method is exception-free
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dump_engine_exception(
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self.vllm_config, scheduler_output, self.scheduler.make_stats()
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)
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raise err
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def _log_err_callback(self, scheduler_output: SchedulerOutput):
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"""Log error details of a future that's not expected to return a result."""
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def callback(f, sched_output=scheduler_output):
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with self.log_error_detail(sched_output):
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result = f.result()
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assert result is None
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return callback
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def step(self) -> tuple[dict[int, EngineCoreOutputs], bool]:
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"""Schedule, execute, and make output.
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Returns tuple of outputs and a flag indicating whether the model
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was executed.
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"""
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# Check for any requests remaining in the scheduler - unfinished,
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# or finished and not yet removed from the batch.
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if not self.scheduler.has_requests():
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return {}, False
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scheduler_output = self.scheduler.schedule()
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future = self.model_executor.execute_model(scheduler_output, non_block=True)
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grammar_output = self.scheduler.get_grammar_bitmask(scheduler_output)
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with self.log_error_detail(scheduler_output):
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model_output = future.result()
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if model_output is None:
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model_output = self.model_executor.sample_tokens(grammar_output)
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# Before processing the model output, process any aborts that happened
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# during the model execution.
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self._process_aborts_queue()
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engine_core_outputs = self.scheduler.update_from_output(
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scheduler_output, model_output
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)
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return engine_core_outputs, scheduler_output.total_num_scheduled_tokens > 0
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def post_step(self, model_executed: bool) -> None:
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# When using async scheduling we can't get draft token ids in advance,
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# so we update draft token ids in the worker process and don't
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# need to update draft token ids here.
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if not self.async_scheduling and self.use_spec_decode and model_executed:
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# Take the draft token ids.
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draft_token_ids = self.model_executor.take_draft_token_ids()
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if draft_token_ids is not None:
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self.scheduler.update_draft_token_ids(draft_token_ids)
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def step_with_batch_queue(
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self,
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) -> tuple[dict[int, EngineCoreOutputs] | None, bool]:
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"""Schedule and execute batches with the batch queue.
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Note that if nothing to output in this step, None is returned.
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The execution flow is as follows:
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1. Try to schedule a new batch if the batch queue is not full.
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If a new batch is scheduled, directly return an empty engine core
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output. In other words, fulfilling the batch queue has a higher priority
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than getting model outputs.
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2. If there is no new scheduled batch, meaning that the batch queue
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is full or no other requests can be scheduled, we block until the first
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batch in the job queue is finished.
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3. Update the scheduler from the output.
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"""
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batch_queue = self.batch_queue
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assert batch_queue is not None
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# Try to schedule a new batch if the batch queue is not full, but
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# the scheduler may return an empty batch if all requests are scheduled.
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# Note that this is not blocking.
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assert len(batch_queue) < self.batch_queue_size
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model_executed = False
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deferred_scheduler_output = None
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if self.scheduler.has_requests():
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scheduler_output = self.scheduler.schedule()
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exec_future = self.model_executor.execute_model(
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scheduler_output, non_block=True
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)
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if not self.is_ec_producer:
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model_executed = scheduler_output.total_num_scheduled_tokens > 0
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if self.is_pooling_model or not model_executed:
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# No sampling required (no requests scheduled).
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future = cast(Future[ModelRunnerOutput], exec_future)
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else:
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exec_future.add_done_callback(self._log_err_callback(scheduler_output))
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if not scheduler_output.pending_structured_output_tokens:
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# We aren't waiting for any tokens, get any grammar output
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# and sample immediately.
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grammar_output = self.scheduler.get_grammar_bitmask(
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scheduler_output
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)
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future = self.model_executor.sample_tokens(
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grammar_output, non_block=True
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)
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else:
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# We need to defer sampling until we have processed the model output
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# from the prior step.
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deferred_scheduler_output = scheduler_output
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if not deferred_scheduler_output:
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# Add this step's future to the queue.
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batch_queue.appendleft((future, scheduler_output))
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if (
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model_executed
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and len(batch_queue) < self.batch_queue_size
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and not batch_queue[-1][0].done()
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):
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# Don't block on next worker response unless the queue is full
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# or there are no more requests to schedule.
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return None, True
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elif not batch_queue:
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# Queue is empty. We should not reach here since this method should
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# only be called when the scheduler contains requests or the queue
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# is non-empty.
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return None, False
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# Block until the next result is available.
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future, scheduler_output = batch_queue.pop()
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with self.log_error_detail(scheduler_output):
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model_output = future.result()
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|
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# Before processing the model output, process any aborts that happened
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# during the model execution.
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self._process_aborts_queue()
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engine_core_outputs = self.scheduler.update_from_output(
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scheduler_output, model_output
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)
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# NOTE(nick): We can either handle the deferred tasks here or save
|
|
# in a field and do it immediately once step_with_batch_queue is
|
|
# re-called. The latter slightly favors TTFT over TPOT/throughput.
|
|
if deferred_scheduler_output:
|
|
# We now have the tokens needed to compute the bitmask for the
|
|
# deferred request. Get the bitmask and call sample tokens.
|
|
grammar_output = self.scheduler.get_grammar_bitmask(
|
|
deferred_scheduler_output
|
|
)
|
|
future = self.model_executor.sample_tokens(grammar_output, non_block=True)
|
|
batch_queue.appendleft((future, deferred_scheduler_output))
|
|
|
|
return engine_core_outputs, model_executed
|
|
|
|
def _process_aborts_queue(self):
|
|
if not self.aborts_queue.empty():
|
|
request_ids = []
|
|
while not self.aborts_queue.empty():
|
|
ids = self.aborts_queue.get_nowait()
|
|
if isinstance(ids, str):
|
|
# Should be a list here, but also handle string just in case.
|
|
ids = (ids,)
|
|
request_ids.extend(ids)
|
|
# More efficient to abort all as a single batch.
|
|
self.abort_requests(request_ids)
|
|
|
|
def shutdown(self):
|
|
self.structured_output_manager.clear_backend()
|
|
if self.model_executor:
|
|
self.model_executor.shutdown()
|
|
if self.scheduler:
|
|
self.scheduler.shutdown()
|
|
|
|
def profile(self, is_start: bool = True):
|
|
self.model_executor.profile(is_start)
|
|
|
|
def reset_mm_cache(self):
|
|
# NOTE: Since this is mainly for debugging, we don't attempt to
|
|
# re-sync the internal caches (P0 sender, P1 receiver)
|
|
if self.scheduler.has_unfinished_requests():
|
|
logger.warning(
|
|
"Resetting the multi-modal cache when requests are "
|
|
"in progress may lead to desynced internal caches."
|
|
)
|
|
|
|
# The cache either exists in EngineCore or WorkerWrapperBase
|
|
if self.mm_receiver_cache is not None:
|
|
self.mm_receiver_cache.clear_cache()
|
|
|
|
self.model_executor.reset_mm_cache()
|
|
|
|
def reset_prefix_cache(self, reset_running_requests: bool = False) -> bool:
|
|
return self.scheduler.reset_prefix_cache(reset_running_requests)
|
|
|
|
def sleep(self, level: int = 1):
|
|
self.model_executor.sleep(level)
|
|
|
|
def wake_up(self, tags: list[str] | None = None):
|
|
self.model_executor.wake_up(tags)
|
|
|
|
def is_sleeping(self) -> bool:
|
|
return self.model_executor.is_sleeping
|
|
|
|
def execute_dummy_batch(self):
|
|
self.model_executor.execute_dummy_batch()
|
|
|
|
def add_lora(self, lora_request: LoRARequest) -> bool:
|
|
return self.model_executor.add_lora(lora_request)
|
|
|
|
def remove_lora(self, lora_id: int) -> bool:
|
|
return self.model_executor.remove_lora(lora_id)
|
|
|
|
def list_loras(self) -> set[int]:
|
|
return self.model_executor.list_loras()
|
|
|
|
def pin_lora(self, lora_id: int) -> bool:
|
|
return self.model_executor.pin_lora(lora_id)
|
|
|
|
def save_sharded_state(
|
|
self,
|
|
path: str,
|
|
pattern: str | None = None,
|
|
max_size: int | None = None,
|
|
) -> None:
|
|
self.model_executor.save_sharded_state(
|
|
path=path, pattern=pattern, max_size=max_size
|
|
)
|
|
|
|
def collective_rpc(
|
|
self,
|
|
method: str | Callable[..., _R],
|
|
timeout: float | None = None,
|
|
args: tuple = (),
|
|
kwargs: dict[str, Any] | None = None,
|
|
) -> list[_R]:
|
|
return self.model_executor.collective_rpc(method, timeout, args, kwargs)
|
|
|
|
def preprocess_add_request(self, request: EngineCoreRequest) -> tuple[Request, int]:
|
|
"""Preprocess the request.
|
|
|
|
This function could be directly used in input processing thread to allow
|
|
request initialization running in parallel with Model forward
|
|
"""
|
|
# Note on thread safety: no race condition.
|
|
# `mm_receiver_cache` is reset at the end of LLMEngine init,
|
|
# and will only be accessed in the input processing thread afterwards.
|
|
if self.mm_receiver_cache is not None and request.mm_features:
|
|
request.mm_features = self.mm_receiver_cache.get_and_update_features(
|
|
request.mm_features
|
|
)
|
|
|
|
req = Request.from_engine_core_request(request, self.request_block_hasher)
|
|
if req.use_structured_output:
|
|
# Note on thread safety: no race condition.
|
|
# `grammar_init` is only invoked in input processing thread. For
|
|
# `structured_output_manager`, each request is independent and
|
|
# grammar compilation is async. Scheduler always checks grammar
|
|
# compilation status before scheduling request.
|
|
self.structured_output_manager.grammar_init(req)
|
|
return req, request.current_wave
|
|
|
|
|
|
class EngineCoreProc(EngineCore):
|
|
"""ZMQ-wrapper for running EngineCore in background process."""
|
|
|
|
ENGINE_CORE_DEAD = b"ENGINE_CORE_DEAD"
|
|
|
|
def __init__(
|
|
self,
|
|
vllm_config: VllmConfig,
|
|
local_client: bool,
|
|
handshake_address: str,
|
|
executor_class: type[Executor],
|
|
log_stats: bool,
|
|
client_handshake_address: str | None = None,
|
|
engine_index: int = 0,
|
|
):
|
|
self.input_queue = queue.Queue[tuple[EngineCoreRequestType, Any]]()
|
|
self.output_queue = queue.Queue[tuple[int, EngineCoreOutputs] | bytes]()
|
|
executor_fail_callback = lambda: self.input_queue.put_nowait(
|
|
(EngineCoreRequestType.EXECUTOR_FAILED, b"")
|
|
)
|
|
|
|
self.engine_index = engine_index
|
|
identity = self.engine_index.to_bytes(length=2, byteorder="little")
|
|
self.engines_running = False
|
|
|
|
with self._perform_handshakes(
|
|
handshake_address,
|
|
identity,
|
|
local_client,
|
|
vllm_config,
|
|
client_handshake_address,
|
|
) as addresses:
|
|
self.client_count = len(addresses.outputs)
|
|
|
|
# Set up data parallel environment.
|
|
self.has_coordinator = addresses.coordinator_output is not None
|
|
self.frontend_stats_publish_address = (
|
|
addresses.frontend_stats_publish_address
|
|
)
|
|
logger.debug(
|
|
"Has DP Coordinator: %s, stats publish address: %s",
|
|
self.has_coordinator,
|
|
self.frontend_stats_publish_address,
|
|
)
|
|
# Only publish request queue stats to coordinator for "internal"
|
|
# and "hybrid" LB modes .
|
|
self.publish_dp_lb_stats = (
|
|
self.has_coordinator
|
|
and not vllm_config.parallel_config.data_parallel_external_lb
|
|
)
|
|
|
|
self._init_data_parallel(vllm_config)
|
|
|
|
super().__init__(
|
|
vllm_config, executor_class, log_stats, executor_fail_callback
|
|
)
|
|
|
|
# Background Threads and Queues for IO. These enable us to
|
|
# overlap ZMQ socket IO with GPU since they release the GIL,
|
|
# and to overlap some serialization/deserialization with the
|
|
# model forward pass.
|
|
# Threads handle Socket <-> Queues and core_busy_loop uses Queue.
|
|
ready_event = threading.Event()
|
|
input_thread = threading.Thread(
|
|
target=self.process_input_sockets,
|
|
args=(
|
|
addresses.inputs,
|
|
addresses.coordinator_input,
|
|
identity,
|
|
ready_event,
|
|
),
|
|
daemon=True,
|
|
)
|
|
input_thread.start()
|
|
|
|
self.output_thread = threading.Thread(
|
|
target=self.process_output_sockets,
|
|
args=(
|
|
addresses.outputs,
|
|
addresses.coordinator_output,
|
|
self.engine_index,
|
|
),
|
|
daemon=True,
|
|
)
|
|
self.output_thread.start()
|
|
|
|
# Don't complete handshake until DP coordinator ready message is
|
|
# received.
|
|
while not ready_event.wait(timeout=10):
|
|
if not input_thread.is_alive():
|
|
raise RuntimeError("Input socket thread died during startup")
|
|
assert addresses.coordinator_input is not None
|
|
logger.info("Waiting for READY message from DP Coordinator...")
|
|
|
|
# Enable environment variable cache (e.g. assume no more
|
|
# environment variable overrides after this point)
|
|
enable_envs_cache()
|
|
|
|
@contextmanager
|
|
def _perform_handshakes(
|
|
self,
|
|
handshake_address: str,
|
|
identity: bytes,
|
|
local_client: bool,
|
|
vllm_config: VllmConfig,
|
|
client_handshake_address: str | None,
|
|
) -> Generator[EngineZmqAddresses, None, None]:
|
|
"""
|
|
Perform startup handshakes.
|
|
|
|
For DP=1 or offline mode, this is with the colocated front-end process.
|
|
|
|
For DP>1 with internal load-balancing this is with the shared front-end
|
|
process which may reside on a different node.
|
|
|
|
For DP>1 with external or hybrid load-balancing, two handshakes are
|
|
performed:
|
|
- With the rank 0 front-end process which retrieves the
|
|
DP Coordinator ZMQ addresses and DP process group address.
|
|
- With the colocated front-end process which retrieves the
|
|
client input/output socket addresses.
|
|
with the exception of the rank 0 and colocated engines themselves which
|
|
don't require the second handshake.
|
|
|
|
Here, "front-end" process can mean the process containing the engine
|
|
core client (which is the API server process in the case the API
|
|
server is not scaled out), OR the launcher process running the
|
|
run_multi_api_server() function in serve.py.
|
|
"""
|
|
input_ctx = zmq.Context()
|
|
is_local = local_client and client_handshake_address is None
|
|
headless = not local_client
|
|
handshake = self._perform_handshake(
|
|
input_ctx,
|
|
handshake_address,
|
|
identity,
|
|
is_local,
|
|
headless,
|
|
vllm_config,
|
|
vllm_config.parallel_config,
|
|
)
|
|
if client_handshake_address is None:
|
|
with handshake as addresses:
|
|
yield addresses
|
|
else:
|
|
assert local_client
|
|
local_handshake = self._perform_handshake(
|
|
input_ctx, client_handshake_address, identity, True, False, vllm_config
|
|
)
|
|
with handshake as addresses, local_handshake as client_addresses:
|
|
addresses.inputs = client_addresses.inputs
|
|
addresses.outputs = client_addresses.outputs
|
|
yield addresses
|
|
|
|
# Update config which may have changed from the handshake
|
|
vllm_config.__post_init__()
|
|
|
|
@contextmanager
|
|
def _perform_handshake(
|
|
self,
|
|
ctx: zmq.Context,
|
|
handshake_address: str,
|
|
identity: bytes,
|
|
local_client: bool,
|
|
headless: bool,
|
|
vllm_config: VllmConfig,
|
|
parallel_config_to_update: ParallelConfig | None = None,
|
|
) -> Generator[EngineZmqAddresses, None, None]:
|
|
with make_zmq_socket(
|
|
ctx,
|
|
handshake_address,
|
|
zmq.DEALER,
|
|
identity=identity,
|
|
linger=5000,
|
|
bind=False,
|
|
) as handshake_socket:
|
|
# Register engine with front-end.
|
|
addresses = self.startup_handshake(
|
|
handshake_socket, local_client, headless, parallel_config_to_update
|
|
)
|
|
yield addresses
|
|
|
|
# Send ready message.
|
|
num_gpu_blocks = vllm_config.cache_config.num_gpu_blocks
|
|
# We pass back the coordinator stats update address here for the
|
|
# external LB case for our colocated front-end to use (coordinator
|
|
# only runs with rank 0).
|
|
dp_stats_address = self.frontend_stats_publish_address
|
|
|
|
# Include config hash for DP configuration validation
|
|
ready_msg = {
|
|
"status": "READY",
|
|
"local": local_client,
|
|
"headless": headless,
|
|
"num_gpu_blocks": num_gpu_blocks,
|
|
"dp_stats_address": dp_stats_address,
|
|
}
|
|
if vllm_config.parallel_config.data_parallel_size > 1:
|
|
ready_msg["parallel_config_hash"] = (
|
|
vllm_config.parallel_config.compute_hash()
|
|
)
|
|
|
|
handshake_socket.send(msgspec.msgpack.encode(ready_msg))
|
|
|
|
@staticmethod
|
|
def startup_handshake(
|
|
handshake_socket: zmq.Socket,
|
|
local_client: bool,
|
|
headless: bool,
|
|
parallel_config: ParallelConfig | None = None,
|
|
) -> EngineZmqAddresses:
|
|
# Send registration message.
|
|
handshake_socket.send(
|
|
msgspec.msgpack.encode(
|
|
{
|
|
"status": "HELLO",
|
|
"local": local_client,
|
|
"headless": headless,
|
|
}
|
|
)
|
|
)
|
|
|
|
# Receive initialization message.
|
|
logger.debug("Waiting for init message from front-end.")
|
|
if not handshake_socket.poll(timeout=HANDSHAKE_TIMEOUT_MINS * 60_000):
|
|
raise RuntimeError(
|
|
"Did not receive response from front-end "
|
|
f"process within {HANDSHAKE_TIMEOUT_MINS} "
|
|
f"minutes"
|
|
)
|
|
init_bytes = handshake_socket.recv()
|
|
init_message: EngineHandshakeMetadata = msgspec.msgpack.decode(
|
|
init_bytes, type=EngineHandshakeMetadata
|
|
)
|
|
logger.debug("Received init message: %s", init_message)
|
|
|
|
if parallel_config is not None:
|
|
for key, value in init_message.parallel_config.items():
|
|
setattr(parallel_config, key, value)
|
|
|
|
return init_message.addresses
|
|
|
|
@staticmethod
|
|
def run_engine_core(*args, dp_rank: int = 0, local_dp_rank: int = 0, **kwargs):
|
|
"""Launch EngineCore busy loop in background process."""
|
|
|
|
# Signal handler used for graceful termination.
|
|
# SystemExit exception is only raised once to allow this and worker
|
|
# processes to terminate without error
|
|
shutdown_requested = False
|
|
|
|
# Ensure we can serialize transformer config after spawning
|
|
maybe_register_config_serialize_by_value()
|
|
|
|
def signal_handler(signum, frame):
|
|
nonlocal shutdown_requested
|
|
if not shutdown_requested:
|
|
shutdown_requested = True
|
|
raise SystemExit()
|
|
|
|
# Either SIGTERM or SIGINT will terminate the engine_core
|
|
signal.signal(signal.SIGTERM, signal_handler)
|
|
signal.signal(signal.SIGINT, signal_handler)
|
|
|
|
engine_core: EngineCoreProc | None = None
|
|
try:
|
|
parallel_config: ParallelConfig = kwargs["vllm_config"].parallel_config
|
|
if parallel_config.data_parallel_size > 1 or dp_rank > 0:
|
|
set_process_title("EngineCore", f"DP{dp_rank}")
|
|
decorate_logs()
|
|
# Set data parallel rank for this engine process.
|
|
parallel_config.data_parallel_rank = dp_rank
|
|
parallel_config.data_parallel_rank_local = local_dp_rank
|
|
engine_core = DPEngineCoreProc(*args, **kwargs)
|
|
else:
|
|
set_process_title("EngineCore")
|
|
decorate_logs()
|
|
engine_core = EngineCoreProc(*args, **kwargs)
|
|
|
|
engine_core.run_busy_loop()
|
|
|
|
except SystemExit:
|
|
logger.debug("EngineCore exiting.")
|
|
raise
|
|
except Exception as e:
|
|
if engine_core is None:
|
|
logger.exception("EngineCore failed to start.")
|
|
else:
|
|
logger.exception("EngineCore encountered a fatal error.")
|
|
engine_core._send_engine_dead()
|
|
raise e
|
|
finally:
|
|
if engine_core is not None:
|
|
engine_core.shutdown()
|
|
|
|
def _init_data_parallel(self, vllm_config: VllmConfig):
|
|
pass
|
|
|
|
def run_busy_loop(self):
|
|
"""Core busy loop of the EngineCore."""
|
|
|
|
# Loop until process is sent a SIGINT or SIGTERM
|
|
while True:
|
|
# 1) Poll the input queue until there is work to do.
|
|
self._process_input_queue()
|
|
# 2) Step the engine core and return the outputs.
|
|
self._process_engine_step()
|
|
|
|
def _process_input_queue(self):
|
|
"""Exits when an engine step needs to be performed."""
|
|
|
|
waited = False
|
|
while (
|
|
not self.engines_running
|
|
and not self.scheduler.has_requests()
|
|
and not self.batch_queue
|
|
):
|
|
if self.input_queue.empty():
|
|
# Drain aborts queue; all aborts are also processed via input_queue.
|
|
with self.aborts_queue.mutex:
|
|
self.aborts_queue.queue.clear()
|
|
if logger.isEnabledFor(DEBUG):
|
|
logger.debug("EngineCore waiting for work.")
|
|
waited = True
|
|
req = self.input_queue.get()
|
|
self._handle_client_request(*req)
|
|
|
|
if waited:
|
|
logger.debug("EngineCore loop active.")
|
|
|
|
# Handle any more client requests.
|
|
while not self.input_queue.empty():
|
|
req = self.input_queue.get_nowait()
|
|
self._handle_client_request(*req)
|
|
|
|
def _process_engine_step(self) -> bool:
|
|
"""Called only when there are unfinished local requests."""
|
|
|
|
# Step the engine core.
|
|
outputs, model_executed = self.step_fn()
|
|
# Put EngineCoreOutputs into the output queue.
|
|
for output in outputs.items() if outputs else ():
|
|
self.output_queue.put_nowait(output)
|
|
# Post-step hook.
|
|
self.post_step(model_executed)
|
|
|
|
return model_executed
|
|
|
|
def _handle_client_request(
|
|
self, request_type: EngineCoreRequestType, request: Any
|
|
) -> None:
|
|
"""Dispatch request from client."""
|
|
|
|
if request_type == EngineCoreRequestType.ADD:
|
|
req, request_wave = request
|
|
self.add_request(req, request_wave)
|
|
elif request_type == EngineCoreRequestType.ABORT:
|
|
self.abort_requests(request)
|
|
elif request_type == EngineCoreRequestType.UTILITY:
|
|
client_idx, call_id, method_name, args = request
|
|
output = UtilityOutput(call_id)
|
|
try:
|
|
method = getattr(self, method_name)
|
|
result = method(*self._convert_msgspec_args(method, args))
|
|
output.result = UtilityResult(result)
|
|
except BaseException as e:
|
|
logger.exception("Invocation of %s method failed", method_name)
|
|
output.failure_message = (
|
|
f"Call to {method_name} method failed: {str(e)}"
|
|
)
|
|
self.output_queue.put_nowait(
|
|
(client_idx, EngineCoreOutputs(utility_output=output))
|
|
)
|
|
elif request_type == EngineCoreRequestType.EXECUTOR_FAILED:
|
|
raise RuntimeError("Executor failed.")
|
|
else:
|
|
logger.error(
|
|
"Unrecognized input request type encountered: %s", request_type
|
|
)
|
|
|
|
@staticmethod
|
|
def _convert_msgspec_args(method, args):
|
|
"""If a provided arg type doesn't match corresponding target method
|
|
arg type, try converting to msgspec object."""
|
|
if not args:
|
|
return args
|
|
arg_types = signature(method).parameters.values()
|
|
assert len(args) <= len(arg_types)
|
|
return tuple(
|
|
msgspec.convert(v, type=p.annotation)
|
|
if isclass(p.annotation)
|
|
and issubclass(p.annotation, msgspec.Struct)
|
|
and not isinstance(v, p.annotation)
|
|
else v
|
|
for v, p in zip(args, arg_types)
|
|
)
|
|
|
|
def _send_engine_dead(self):
|
|
"""Send EngineDead status to the EngineCoreClient."""
|
|
|
|
# Put ENGINE_CORE_DEAD in the queue.
|
|
self.output_queue.put_nowait(EngineCoreProc.ENGINE_CORE_DEAD)
|
|
|
|
# Wait until msg sent by the daemon before shutdown.
|
|
self.output_thread.join(timeout=5.0)
|
|
if self.output_thread.is_alive():
|
|
logger.fatal(
|
|
"vLLM shutdown signal from EngineCore failed "
|
|
"to send. Please report this issue."
|
|
)
|
|
|
|
def process_input_sockets(
|
|
self,
|
|
input_addresses: list[str],
|
|
coord_input_address: str | None,
|
|
identity: bytes,
|
|
ready_event: threading.Event,
|
|
):
|
|
"""Input socket IO thread."""
|
|
|
|
# Msgpack serialization decoding.
|
|
add_request_decoder = MsgpackDecoder(EngineCoreRequest)
|
|
generic_decoder = MsgpackDecoder()
|
|
|
|
with ExitStack() as stack, zmq.Context() as ctx:
|
|
input_sockets = [
|
|
stack.enter_context(
|
|
make_zmq_socket(
|
|
ctx, input_address, zmq.DEALER, identity=identity, bind=False
|
|
)
|
|
)
|
|
for input_address in input_addresses
|
|
]
|
|
if coord_input_address is None:
|
|
coord_socket = None
|
|
else:
|
|
coord_socket = stack.enter_context(
|
|
make_zmq_socket(
|
|
ctx,
|
|
coord_input_address,
|
|
zmq.XSUB,
|
|
identity=identity,
|
|
bind=False,
|
|
)
|
|
)
|
|
# Send subscription message to coordinator.
|
|
coord_socket.send(b"\x01")
|
|
|
|
# Register sockets with poller.
|
|
poller = zmq.Poller()
|
|
for input_socket in input_sockets:
|
|
# Send initial message to each input socket - this is required
|
|
# before the front-end ROUTER socket can send input messages
|
|
# back to us.
|
|
input_socket.send(b"")
|
|
poller.register(input_socket, zmq.POLLIN)
|
|
|
|
if coord_socket is not None:
|
|
# Wait for ready message from coordinator.
|
|
assert coord_socket.recv() == b"READY"
|
|
poller.register(coord_socket, zmq.POLLIN)
|
|
|
|
ready_event.set()
|
|
del ready_event
|
|
while True:
|
|
for input_socket, _ in poller.poll():
|
|
# (RequestType, RequestData)
|
|
type_frame, *data_frames = input_socket.recv_multipart(copy=False)
|
|
request_type = EngineCoreRequestType(bytes(type_frame.buffer))
|
|
|
|
# Deserialize the request data.
|
|
if request_type == EngineCoreRequestType.ADD:
|
|
request = add_request_decoder.decode(data_frames)
|
|
request = self.preprocess_add_request(request)
|
|
else:
|
|
request = generic_decoder.decode(data_frames)
|
|
|
|
if request_type == EngineCoreRequestType.ABORT:
|
|
# Aborts are added to *both* queues, allows us to eagerly
|
|
# process aborts while also ensuring ordering in the input
|
|
# queue to avoid leaking requests. This is ok because
|
|
# aborting in the scheduler is idempotent.
|
|
self.aborts_queue.put_nowait(request)
|
|
|
|
# Push to input queue for core busy loop.
|
|
self.input_queue.put_nowait((request_type, request))
|
|
|
|
def process_output_sockets(
|
|
self,
|
|
output_paths: list[str],
|
|
coord_output_path: str | None,
|
|
engine_index: int,
|
|
):
|
|
"""Output socket IO thread."""
|
|
|
|
# Msgpack serialization encoding.
|
|
encoder = MsgpackEncoder()
|
|
# Send buffers to reuse.
|
|
reuse_buffers: list[bytearray] = []
|
|
# Keep references to outputs and buffers until zmq is finished
|
|
# with them (outputs may contain tensors/np arrays whose
|
|
# backing buffers were extracted for zero-copy send).
|
|
pending = deque[tuple[zmq.MessageTracker, Any, bytearray]]()
|
|
|
|
# We must set linger to ensure the ENGINE_CORE_DEAD
|
|
# message is sent prior to closing the socket.
|
|
with ExitStack() as stack, zmq.Context() as ctx:
|
|
sockets = [
|
|
stack.enter_context(
|
|
make_zmq_socket(ctx, output_path, zmq.PUSH, linger=4000)
|
|
)
|
|
for output_path in output_paths
|
|
]
|
|
coord_socket = (
|
|
stack.enter_context(
|
|
make_zmq_socket(
|
|
ctx, coord_output_path, zmq.PUSH, bind=False, linger=4000
|
|
)
|
|
)
|
|
if coord_output_path is not None
|
|
else None
|
|
)
|
|
max_reuse_bufs = len(sockets) + 1
|
|
|
|
while True:
|
|
output = self.output_queue.get()
|
|
if output == EngineCoreProc.ENGINE_CORE_DEAD:
|
|
for socket in sockets:
|
|
socket.send(output)
|
|
break
|
|
assert not isinstance(output, bytes)
|
|
client_index, outputs = output
|
|
outputs.engine_index = engine_index
|
|
|
|
if client_index == -1:
|
|
# Don't reuse buffer for coordinator message
|
|
# which will be very small.
|
|
assert coord_socket is not None
|
|
coord_socket.send_multipart(encoder.encode(outputs))
|
|
continue
|
|
|
|
# Reclaim buffers that zmq is finished with.
|
|
while pending and pending[-1][0].done:
|
|
reuse_buffers.append(pending.pop()[2])
|
|
|
|
buffer = reuse_buffers.pop() if reuse_buffers else bytearray()
|
|
buffers = encoder.encode_into(outputs, buffer)
|
|
tracker = sockets[client_index].send_multipart(
|
|
buffers, copy=False, track=True
|
|
)
|
|
if not tracker.done:
|
|
ref = outputs if len(buffers) > 1 else None
|
|
pending.appendleft((tracker, ref, buffer))
|
|
elif len(reuse_buffers) < max_reuse_bufs:
|
|
# Limit the number of buffers to reuse.
|
|
reuse_buffers.append(buffer)
|
|
|
|
|
|
class DPEngineCoreProc(EngineCoreProc):
|
|
"""ZMQ-wrapper for running EngineCore in background process
|
|
in a data parallel context."""
|
|
|
|
def __init__(
|
|
self,
|
|
vllm_config: VllmConfig,
|
|
local_client: bool,
|
|
handshake_address: str,
|
|
executor_class: type[Executor],
|
|
log_stats: bool,
|
|
client_handshake_address: str | None = None,
|
|
):
|
|
# Counts forward-passes of the model so that we can synchronize
|
|
# finished with DP peers every N steps.
|
|
self.step_counter = 0
|
|
self.current_wave = 0
|
|
self.last_counts = (0, 0)
|
|
|
|
# Initialize the engine.
|
|
dp_rank = vllm_config.parallel_config.data_parallel_rank
|
|
super().__init__(
|
|
vllm_config,
|
|
local_client,
|
|
handshake_address,
|
|
executor_class,
|
|
log_stats,
|
|
client_handshake_address,
|
|
dp_rank,
|
|
)
|
|
|
|
def _init_data_parallel(self, vllm_config: VllmConfig):
|
|
# Configure GPUs and stateless process group for data parallel.
|
|
dp_rank = vllm_config.parallel_config.data_parallel_rank
|
|
dp_size = vllm_config.parallel_config.data_parallel_size
|
|
local_dp_rank = vllm_config.parallel_config.data_parallel_rank_local
|
|
|
|
assert dp_size > 1
|
|
assert local_dp_rank is not None
|
|
assert 0 <= local_dp_rank <= dp_rank < dp_size
|
|
|
|
if vllm_config.kv_transfer_config is not None:
|
|
# modify the engine_id and append the local_dp_rank to it to ensure
|
|
# that the kv_transfer_config is unique for each DP rank.
|
|
vllm_config.kv_transfer_config.engine_id = (
|
|
f"{vllm_config.kv_transfer_config.engine_id}_dp{local_dp_rank}"
|
|
)
|
|
logger.debug(
|
|
"Setting kv_transfer_config.engine_id to %s",
|
|
vllm_config.kv_transfer_config.engine_id,
|
|
)
|
|
|
|
self.dp_rank = dp_rank
|
|
self.dp_group = vllm_config.parallel_config.stateless_init_dp_group()
|
|
|
|
def shutdown(self):
|
|
super().shutdown()
|
|
if dp_group := getattr(self, "dp_group", None):
|
|
stateless_destroy_torch_distributed_process_group(dp_group)
|
|
|
|
def add_request(self, request: Request, request_wave: int = 0):
|
|
if self.has_coordinator and request_wave != self.current_wave:
|
|
if request_wave > self.current_wave:
|
|
self.current_wave = request_wave
|
|
elif not self.engines_running:
|
|
# Request received for an already-completed wave, notify
|
|
# front-end that we need to start the next one.
|
|
self.output_queue.put_nowait(
|
|
(-1, EngineCoreOutputs(start_wave=self.current_wave))
|
|
)
|
|
|
|
super().add_request(request, request_wave)
|
|
|
|
def _handle_client_request(
|
|
self, request_type: EngineCoreRequestType, request: Any
|
|
) -> None:
|
|
if request_type == EngineCoreRequestType.START_DP_WAVE:
|
|
new_wave, exclude_eng_index = request
|
|
if exclude_eng_index != self.engine_index and (
|
|
new_wave >= self.current_wave
|
|
):
|
|
self.current_wave = new_wave
|
|
if not self.engines_running:
|
|
logger.debug("EngineCore starting idle loop for wave %d.", new_wave)
|
|
self.engines_running = True
|
|
else:
|
|
super()._handle_client_request(request_type, request)
|
|
|
|
def _maybe_publish_request_counts(self):
|
|
if not self.publish_dp_lb_stats:
|
|
return
|
|
|
|
# Publish our request counts (if they've changed).
|
|
counts = self.scheduler.get_request_counts()
|
|
if counts != self.last_counts:
|
|
self.last_counts = counts
|
|
stats = SchedulerStats(
|
|
*counts, step_counter=self.step_counter, current_wave=self.current_wave
|
|
)
|
|
self.output_queue.put_nowait((-1, EngineCoreOutputs(scheduler_stats=stats)))
|
|
|
|
def run_busy_loop(self):
|
|
"""Core busy loop of the EngineCore for data parallel case."""
|
|
|
|
# Loop until process is sent a SIGINT or SIGTERM
|
|
while True:
|
|
# 1) Poll the input queue until there is work to do.
|
|
self._process_input_queue()
|
|
|
|
# 2) Step the engine core.
|
|
executed = self._process_engine_step()
|
|
self._maybe_publish_request_counts()
|
|
|
|
local_unfinished_reqs = self.scheduler.has_unfinished_requests()
|
|
if not executed:
|
|
if not local_unfinished_reqs and not self.engines_running:
|
|
# All engines are idle.
|
|
continue
|
|
|
|
# We are in a running state and so must execute a dummy pass
|
|
# if the model didn't execute any ready requests.
|
|
self.execute_dummy_batch()
|
|
|
|
# 3) All-reduce operation to determine global unfinished reqs.
|
|
self.engines_running = self._has_global_unfinished_reqs(
|
|
local_unfinished_reqs
|
|
)
|
|
|
|
if not self.engines_running:
|
|
if self.dp_rank == 0 or not self.has_coordinator:
|
|
# Notify client that we are pausing the loop.
|
|
logger.debug(
|
|
"Wave %d finished, pausing engine loop.", self.current_wave
|
|
)
|
|
# In the coordinator case, dp rank 0 sends updates to the
|
|
# coordinator. Otherwise (offline spmd case), each rank
|
|
# sends the update to its colocated front-end process.
|
|
client_index = -1 if self.has_coordinator else 0
|
|
self.output_queue.put_nowait(
|
|
(
|
|
client_index,
|
|
EngineCoreOutputs(wave_complete=self.current_wave),
|
|
)
|
|
)
|
|
# Increment wave count and reset step counter.
|
|
self.current_wave += 1
|
|
self.step_counter = 0
|
|
|
|
def _has_global_unfinished_reqs(self, local_unfinished: bool) -> bool:
|
|
# Optimization - only perform finish-sync all-reduce every 32 steps.
|
|
self.step_counter += 1
|
|
if self.step_counter % 32 != 0:
|
|
return True
|
|
|
|
return ParallelConfig.has_unfinished_dp(self.dp_group, local_unfinished)
|
|
|
|
def reinitialize_distributed(
|
|
self, reconfig_request: ReconfigureDistributedRequest
|
|
) -> None:
|
|
stateless_destroy_torch_distributed_process_group(self.dp_group)
|
|
self.shutdown()
|
|
|
|
parallel_config = self.vllm_config.parallel_config
|
|
old_dp_size = parallel_config.data_parallel_size
|
|
parallel_config.data_parallel_size = reconfig_request.new_data_parallel_size
|
|
if reconfig_request.new_data_parallel_rank != -1:
|
|
parallel_config.data_parallel_rank = reconfig_request.new_data_parallel_rank
|
|
# local rank specifies device visibility, it should not be changed
|
|
assert (
|
|
reconfig_request.new_data_parallel_rank_local
|
|
== ReconfigureRankType.KEEP_CURRENT_RANK
|
|
)
|
|
parallel_config.data_parallel_master_ip = (
|
|
reconfig_request.new_data_parallel_master_ip
|
|
)
|
|
parallel_config.data_parallel_master_port = (
|
|
reconfig_request.new_data_parallel_master_port
|
|
)
|
|
if reconfig_request.new_data_parallel_rank != -2:
|
|
self.dp_rank = parallel_config.data_parallel_rank
|
|
self.dp_group = parallel_config.stateless_init_dp_group()
|
|
reconfig_request.new_data_parallel_master_port = (
|
|
parallel_config.data_parallel_master_port
|
|
)
|
|
|
|
self.model_executor.reinitialize_distributed(reconfig_request)
|
|
if reconfig_request.new_data_parallel_size > old_dp_size:
|
|
assert self.available_gpu_memory_for_kv_cache > 0
|
|
# pass available_gpu_memory_for_kv_cache from existing
|
|
# engine-cores to new engine-cores so they can directly
|
|
# use it in _initialize_kv_caches() rather than profiling.
|
|
ParallelConfig.sync_kv_cache_memory_size(
|
|
self.dp_group, self.available_gpu_memory_for_kv_cache
|
|
)
|
|
# NOTE(yongji): newly joined workers require dummy_run even
|
|
# CUDA graph is not used
|
|
self.model_executor.collective_rpc("compile_or_warm_up_model")
|
|
if (
|
|
reconfig_request.new_data_parallel_rank
|
|
== ReconfigureRankType.SHUTDOWN_CURRENT_RANK
|
|
):
|
|
self.shutdown()
|
|
logger.info("DPEngineCoreProc %s shutdown", self.dp_rank)
|
|
else:
|
|
logger.info(
|
|
"Distributed environment reinitialized for DP rank %s", self.dp_rank
|
|
)
|
|
|
|
|
|
class DPEngineCoreActor(DPEngineCoreProc):
|
|
"""
|
|
Ray actor for running EngineCore in a data parallel context
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
vllm_config: VllmConfig,
|
|
local_client: bool,
|
|
addresses: EngineZmqAddresses,
|
|
executor_class: type[Executor],
|
|
log_stats: bool,
|
|
dp_rank: int = 0,
|
|
local_dp_rank: int = 0,
|
|
):
|
|
self.addresses = addresses
|
|
vllm_config.parallel_config.data_parallel_rank = dp_rank
|
|
vllm_config.parallel_config.data_parallel_rank_local = local_dp_rank
|
|
|
|
# Set CUDA_VISIBLE_DEVICES as early as possible in actor life cycle
|
|
# NOTE: in MP we set CUDA_VISIBLE_DEVICES at process creation time,
|
|
# and this cannot be done in the same way for Ray because:
|
|
# 1) Ray manages life cycle of all ray workers (including
|
|
# DPEngineCoreActor)
|
|
# 2) Ray sets CUDA_VISIBLE_DEVICES based on num_gpus configuration
|
|
# To bypass 2, we need to also set
|
|
# RAY_EXPERIMENTAL_NOSET_CUDA_VISIBLE_DEVICES, but vLLM workers created
|
|
# thereafter would have CUDA_VISIBLE_DEVICES set, which is sticky:
|
|
# https://github.com/ray-project/ray/blob/e752fc319ddedd9779a0989b6d3613909bad75c9/python/ray/_private/worker.py#L456 # noqa: E501
|
|
# This is problematic because when the vLLM worker (a Ray actor)
|
|
# executes a task, it indexes into the sticky CUDA_VISIBLE_DEVICES
|
|
# rather than directly using the GPU ID, potentially resulting in
|
|
# index out of bounds error. See:
|
|
# https://github.com/ray-project/ray/pull/40461/files#diff-31e8159767361e4bc259b6d9883d9c0d5e5db780fcea4a52ead4ee3ee4a59a78R1860 # noqa: E501
|
|
# and get_accelerator_ids_for_accelerator_resource() in worker.py
|
|
# of ray.
|
|
self._set_visible_devices(vllm_config, local_dp_rank)
|
|
|
|
super().__init__(vllm_config, local_client, "", executor_class, log_stats)
|
|
|
|
def _set_visible_devices(self, vllm_config: VllmConfig, local_dp_rank: int):
|
|
from vllm.platforms import current_platform
|
|
|
|
if current_platform.is_xpu():
|
|
pass
|
|
else:
|
|
device_control_env_var = current_platform.device_control_env_var
|
|
self._set_cuda_visible_devices(
|
|
vllm_config, local_dp_rank, device_control_env_var
|
|
)
|
|
|
|
def _set_cuda_visible_devices(
|
|
self, vllm_config: VllmConfig, local_dp_rank: int, device_control_env_var: str
|
|
):
|
|
world_size = vllm_config.parallel_config.world_size
|
|
# Set CUDA_VISIBLE_DEVICES or equivalent.
|
|
try:
|
|
value = get_device_indices(
|
|
device_control_env_var, local_dp_rank, world_size
|
|
)
|
|
os.environ[device_control_env_var] = value
|
|
except IndexError as e:
|
|
raise Exception(
|
|
f"Error setting {device_control_env_var}: "
|
|
f"local range: [{local_dp_rank * world_size}, "
|
|
f"{(local_dp_rank + 1) * world_size}) "
|
|
f'base value: "{os.getenv(device_control_env_var)}"'
|
|
) from e
|
|
|
|
@contextmanager
|
|
def _perform_handshakes(
|
|
self,
|
|
handshake_address: str,
|
|
identity: bytes,
|
|
local_client: bool,
|
|
vllm_config: VllmConfig,
|
|
client_handshake_address: str | None,
|
|
):
|
|
"""
|
|
For Ray, we don't need to actually perform handshake.
|
|
All addresses information is known before the actor creation.
|
|
Therefore, we simply yield these addresses.
|
|
"""
|
|
yield self.addresses
|
|
|
|
def wait_for_init(self):
|
|
"""
|
|
Wait until the engine core is initialized.
|
|
|
|
This is just an empty method. When ray.get() on this method
|
|
(or any other method of the actor) returns, it is guaranteed
|
|
that actor creation (i.e., __init__) is complete.
|
|
"""
|
|
pass
|
|
|
|
def run(self):
|
|
"""
|
|
Run the engine core busy loop.
|
|
"""
|
|
try:
|
|
self.run_busy_loop()
|
|
except SystemExit:
|
|
logger.debug("EngineCore exiting.")
|
|
raise
|
|
except Exception:
|
|
logger.exception("EngineCore encountered a fatal error.")
|
|
raise
|
|
finally:
|
|
self.shutdown()
|