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sglang/python/sglang/srt/managers/session_controller.py

310 lines
12 KiB
Python

# Copyright 2023-2024 SGLang Team
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
from __future__ import annotations
import logging
import time
import uuid
from typing import TYPE_CHECKING, Dict, Optional
from sglang.srt.managers.io_struct import (
CloseSessionReqInput,
OpenSessionReqInput,
OpenSessionReqOutput,
TokenizedGenerateReqInput,
)
from sglang.srt.managers.schedule_batch import FINISH_ABORT, Req
from sglang.srt.mem_cache.session_aware_cache import SessionAwareCache
if TYPE_CHECKING:
from sglang.srt.mem_cache.base_prefix_cache import BasePrefixCache
logger = logging.getLogger(__name__)
class SessionReqNode:
def __init__(
self,
req: Req,
parent: Optional["SessionReqNode"] = None,
children=None,
):
self.req = req
self.parent = parent
if parent is not None:
parent.children.append(self)
self.children = [] if not children else children
def clear_children(self, req_dict):
for req_node in self.children:
req_node.clear(req_dict)
self.children = []
def clear(self, req_dict):
for req_node in self.children:
req_node.clear(req_dict)
if self.req.finished_reason is None:
self.req.to_finish = FINISH_ABORT()
del req_dict[self.req.rid]
def abort(self):
if self.req.finished_reason is None:
self.req.to_finish = FINISH_ABORT()
def __str__(self):
return self._str_helper(self.req.rid)
def _str_helper(self, prefix=""):
if len(self.children) == 0:
return prefix + "\n"
else:
origin_prefix = prefix
prefix += " -- " + self.children[0].req.rid
ret = self.children[0]._str_helper(prefix)
for child in self.children[1:]:
prefix = " " * len(origin_prefix) + " \\- " + child.req.rid
ret += child._str_helper(prefix)
return ret
class Session:
def __init__(
self,
capacity_of_str_len: int,
session_id: Optional[str] = None,
streaming: bool = False,
timeout: Optional[float] = None,
):
self.session_id = session_id if session_id is not None else uuid.uuid4().hex
self.capacity_of_str_len = capacity_of_str_len
self.streaming = streaming
self.timeout = timeout
self.last_active_time: float = time.monotonic()
self.req_nodes: Dict[str, SessionReqNode] = {}
def is_timed_out(self) -> bool:
if self.timeout is None:
return False
return time.monotonic() - self.last_active_time > self.timeout
def create_req(
self,
req: TokenizedGenerateReqInput,
tokenizer,
vocab_size: int,
eos_token_ids=None,
):
assert req.session_params is not None
self.last_active_time = time.monotonic()
session_params = req.session_params
last_req_node = None
last_req = None
abort = False
abort_message = ""
if self.streaming:
# Streaming sessions: only simple appends allowed; reject otherwise.
if session_params.replace:
abort = True
abort_message = "Streaming sessions do not support replace."
elif session_params.drop_previous_output:
abort = True
abort_message = (
"Streaming sessions do not support drop_previous_output."
)
elif session_params.offset and session_params.offset != 0:
abort = True
abort_message = "Streaming sessions do not support offset."
elif self.req_nodes:
assert len(self.req_nodes) == 1
_, last_req_node = self.req_nodes.popitem()
last_req = last_req_node.req
elif session_params.replace:
if session_params.rid is None:
for _, req_node in self.req_nodes.items():
req_node.clear(self.req_nodes)
else:
if session_params.rid not in self.req_nodes:
abort = True
abort_message = "Invalid request session id"
else:
last_req_node = self.req_nodes[session_params.rid]
last_req_node.abort()
last_req = last_req_node.req
last_req_node.clear_children(self.req_nodes)
else:
if session_params.rid is not None:
if session_params.rid not in self.req_nodes:
abort = True
abort_message = "Invalid request session id"
else:
last_req_node = self.req_nodes[session_params.rid]
last_req = last_req_node.req
if not last_req.finished():
abort = True
abort_message = "Session request is appending to a request that hasn't finished."
logging.warning(abort_message)
if last_req is not None:
# trim bos token if it is an append
if (
tokenizer is not None
and req.input_ids
and req.input_ids[0] == tokenizer.bos_token_id
):
req.input_ids = req.input_ids[1:]
input_ids = (
last_req.origin_input_ids
+ last_req.output_ids[: last_req.sampling_params.max_new_tokens]
)
if session_params.drop_previous_output:
input_ids = last_req.origin_input_ids[:]
if session_params.offset and session_params.offset != 0:
input_ids = input_ids[: session_params.offset] + req.input_ids
else:
input_ids += req.input_ids
input_ids_unpadded = (
last_req.origin_input_ids_unpadded
+ last_req.output_ids[: last_req.sampling_params.max_new_tokens]
)
if session_params.drop_previous_output:
input_ids_unpadded = last_req.origin_input_ids_unpadded[:]
if session_params.offset and session_params.offset != 0:
input_ids_unpadded = (
input_ids_unpadded[: session_params.offset] + req.input_ids
)
else:
input_ids_unpadded += req.input_ids
else:
input_ids = req.input_ids
input_ids_unpadded = req.input_ids
new_req = Req(
rid=req.rid,
origin_input_text=None,
origin_input_ids=input_ids,
origin_input_ids_unpadded=input_ids_unpadded,
sampling_params=req.sampling_params,
lora_id=req.lora_id,
session=self,
custom_logit_processor=req.custom_logit_processor,
stream=req.stream,
return_logprob=req.return_logprob,
top_logprobs_num=req.top_logprobs_num,
token_ids_logprob=req.token_ids_logprob,
vocab_size=vocab_size,
eos_token_ids=eos_token_ids,
require_reasoning=req.require_reasoning,
return_hidden_states=req.return_hidden_states,
return_routed_experts=req.return_routed_experts,
priority=req.priority,
routing_key=req.routing_key,
http_worker_ipc=req.http_worker_ipc,
time_stats=req.time_stats,
)
if last_req is not None:
new_req.multimodal_inputs = last_req.multimodal_inputs
new_req.tokenizer = tokenizer
if abort:
new_req.set_finish_with_abort(abort_message)
elif self.streaming:
if last_req is not None:
last_req.session = None
self.req_nodes[req.rid] = SessionReqNode(new_req)
else:
new_req_node = SessionReqNode(new_req, last_req_node)
self.req_nodes[req.rid] = new_req_node
return new_req
class SessionController:
def __init__(self, tree_cache: BasePrefixCache):
self.sessions: Dict[str, Session] = {}
self._last_reap_time: float = 0.0
self.tree_cache = tree_cache
def __contains__(self, session_id: str) -> bool:
return session_id in self.sessions
def get(self, session_id: str) -> Optional[Session]:
return self.sessions.get(session_id)
def open(self, recv_req: OpenSessionReqInput) -> OpenSessionReqOutput:
session_id = recv_req.session_id
if session_id in self.sessions:
logger.warning(f"session id {session_id} already exist, cannot open.")
return OpenSessionReqOutput(session_id, False)
elif session_id is None:
logger.warning("session id is None, cannot open.")
return OpenSessionReqOutput(session_id, False)
else:
self.sessions[session_id] = Session(
recv_req.capacity_of_str_len,
session_id,
streaming=bool(recv_req.streaming),
timeout=recv_req.timeout,
)
return OpenSessionReqOutput(session_id, True)
def close(self, recv_req: CloseSessionReqInput):
session_id = recv_req.session_id
if session_id not in self.sessions:
logger.warning(f"session id {session_id} does not exist, cannot delete.")
else:
self._close(session_id)
def _close(self, session_id: str):
session = self.sessions[session_id]
if session.streaming and session.req_nodes:
assert len(session.req_nodes) == 1
req = next(iter(session.req_nodes.values())).req
if not req.finished():
req.session = None
if isinstance(self.tree_cache, SessionAwareCache):
self.tree_cache.release_session(session_id)
del self.sessions[session_id]
def maybe_reap(self, now: float, interval: float = 1.0):
# reap sessions every second
if now - self._last_reap_time > interval:
self._last_reap_time = now
timed_out = [
sid for sid, session in self.sessions.items() if session.is_timed_out()
]
for sid in timed_out:
logger.info(f"Session {sid} timed out, closing.")
self._close(sid)
@staticmethod
def adjust_mm_offsets(recv_req: TokenizedGenerateReqInput, req: Req, image_inputs):
# For session requests, adjust mm_inputs offsets by the prefix length.
# Session.create_req prepends previous context to origin_input_ids,
# so offsets from the new prompt need to be shifted.
if len(recv_req.input_ids) >= len(req.origin_input_ids):
return
prefix_len = len(req.origin_input_ids) - len(recv_req.input_ids)
for mm_item in image_inputs.mm_items:
if mm_item.offsets:
mm_item.offsets = [
(start + prefix_len, end + prefix_len)
for start, end in mm_item.offsets
]