Files
sglang/python/sglang/srt/constrained/grammar_manager.py

199 lines
7.8 KiB
Python

from __future__ import annotations
import logging
import time
from concurrent import futures
from typing import TYPE_CHECKING, List
import torch
from sglang.srt.constrained.base_grammar_backend import (
INVALID_GRAMMAR_OBJ,
create_grammar_backend,
)
from sglang.srt.environ import envs
if TYPE_CHECKING:
from sglang.srt.managers.io_struct import AbortReq
from sglang.srt.managers.schedule_batch import Req
from sglang.srt.managers.scheduler import Scheduler
logger = logging.getLogger(__name__)
class GrammarManager:
def __init__(self, scheduler: Scheduler):
self.scheduler = scheduler
self.server_args = scheduler.server_args
self.grammar_queue: List[Req] = []
if not self.server_args.skip_tokenizer_init:
self.grammar_backend = create_grammar_backend(
self.server_args,
scheduler.tokenizer,
scheduler.model_config.vocab_size,
scheduler.model_config.hf_eos_token_id,
)
else:
self.grammar_backend = None
self.grammar_sync_group = scheduler.dp_tp_cpu_group
self.grammar_sync_size = scheduler.dp_tp_group.world_size
self.grammar_sync_entry = scheduler.dp_tp_group.first_rank
self.is_grammar_sync_entry = scheduler.dp_tp_group.is_first_rank
self.SGLANG_GRAMMAR_POLL_INTERVAL = envs.SGLANG_GRAMMAR_POLL_INTERVAL.get()
self.SGLANG_GRAMMAR_MAX_POLL_ITERATIONS = (
envs.SGLANG_GRAMMAR_MAX_POLL_ITERATIONS.get()
)
def __len__(self):
return len(self.grammar_queue)
def clear(self):
if self.grammar_backend:
self.grammar_backend.reset()
def has_waiting_grammars(self) -> bool:
return len(self.grammar_queue) > 0
def abort_requests(self, recv_req: AbortReq):
for req in self.grammar_queue:
if recv_req.abort_all or req.rid.startswith(recv_req.rid):
logger.debug(f"Abort grammar queue request. {req.rid=}")
if isinstance(req.grammar, futures.Future) and req.grammar:
req.grammar.cancel()
req.set_finish_with_abort("Aborted by AbortReq.")
def process_req_with_grammar(self, req: Req) -> bool:
# Init grammar cache for this request
add_to_grammar_queue = False
if (
req.sampling_params.json_schema is not None
or req.sampling_params.regex is not None
or req.sampling_params.ebnf is not None
or req.sampling_params.structural_tag is not None
):
if self.grammar_backend is None:
error_msg = "Grammar-based generation (json_schema, regex, ebnf, structural_tag) is not supported when the server is launched with --grammar-backend none"
req.set_finish_with_abort(error_msg)
else:
if req.sampling_params.json_schema is not None:
key = ("json", req.sampling_params.json_schema)
elif req.sampling_params.regex is not None:
key = ("regex", req.sampling_params.regex)
elif req.sampling_params.ebnf is not None:
key = ("ebnf", req.sampling_params.ebnf)
elif req.sampling_params.structural_tag:
key = ("structural_tag", req.sampling_params.structural_tag)
value, cache_hit = self.grammar_backend.get_cached_or_future_value(
key, req.require_reasoning
)
req.grammar = value
if not cache_hit:
req.grammar_key = key
add_to_grammar_queue = True
else:
if value is INVALID_GRAMMAR_OBJ: # We hit a cached invalid grammar.
error_msg = f"Invalid grammar request with cache hit: {key=}"
req.set_finish_with_abort(error_msg)
if add_to_grammar_queue:
self.grammar_queue.append(req)
return add_to_grammar_queue
def get_ready_grammar_requests(self) -> List[Req]:
"""
Move requests whose grammar objects are ready from grammar_queue to waiting_queue.
Rank i returns two sets ready_reqs_i, failed_reqs_i
ready_reqs_all = all_gather(ready_reqs_i)
failed_reqs_all = all_gather(failed_reqs_i)
ready_reqs = intersect(ready_reqs_all)
failed_reqs = union(failed_reqs_all)
"""
assert self.grammar_backend
ready_req_idxs: set[int] = set()
failed_req_idxs: set[int] = set()
# Poll for ready requests
start_time = time.perf_counter()
while time.perf_counter() - start_time < self.SGLANG_GRAMMAR_POLL_INTERVAL:
for i, req in enumerate(self.grammar_queue):
if i in ready_req_idxs:
continue
if req.finished() or req.grammar is None: # It is aborted by AbortReq
ready_req_idxs.add(i)
continue
assert isinstance(req.grammar, futures.Future), f"{req=}"
if req.grammar.done():
ready_req_idxs.add(i)
# Sleep a bit to avoid busy waiting
time.sleep(self.SGLANG_GRAMMAR_POLL_INTERVAL / 10)
# Check failed requests
for i, req in enumerate(self.grammar_queue):
if i not in ready_req_idxs:
self.grammar_queue[i].grammar_wait_ct += 1
if (
self.grammar_queue[i].grammar_wait_ct
>= self.SGLANG_GRAMMAR_MAX_POLL_ITERATIONS
):
# Timeout after max poll iterations
# The actual waiting time is SGLANG_GRAMMAR_MAX_POLL_ITERATIONS * max(SGLANG_GRAMMAR_POLL_INTERVAL, GPU_forward_batch_latency)
failed_req_idxs.add(i)
# Sync ready and failed requests across all ranks
if self.grammar_sync_size == 1:
synced_ready_req_idxs = ready_req_idxs
synced_failed_req_idxs = failed_req_idxs
else:
all_gather_output = [None] * self.grammar_sync_size
torch.distributed.all_gather_object(
all_gather_output,
(ready_req_idxs, failed_req_idxs),
group=self.grammar_sync_group,
)
synced_ready_req_idxs = set.intersection(*[x[0] for x in all_gather_output])
synced_failed_req_idxs = set.union(*[x[1] for x in all_gather_output])
# Return ready requests
return_reqs: List[Req] = []
for i in synced_ready_req_idxs:
req = self.grammar_queue[i]
return_reqs.append(req)
if req.finished() or req.grammar is None: # It is aborted by AbortReq
continue
assert isinstance(req.grammar, futures.Future) and req.grammar_key
req.grammar = req.grammar.result()
self.grammar_backend.set_cache(req.grammar_key, req.grammar.copy())
if req.grammar is INVALID_GRAMMAR_OBJ:
error_msg = f"Invalid grammar request: {req.grammar_key=}"
req.set_finish_with_abort(error_msg)
# Return failed requests
for i in synced_failed_req_idxs:
req = self.grammar_queue[i]
return_reqs.append(req)
assert isinstance(req.grammar, futures.Future) and req.grammar_key
req.grammar.cancel()
self.grammar_backend.set_cache(req.grammar_key, INVALID_GRAMMAR_OBJ)
error_msg = f"Grammar preprocessing timed out: {req.grammar_key=}"
req.set_finish_with_abort(error_msg)
# Remove finished requests from grammar_queue
self.grammar_queue = [
req
for i, req in enumerate(self.grammar_queue)
if i not in synced_ready_req_idxs and i not in synced_failed_req_idxs
]
return return_reqs