Files
sglang/python/sglang/srt/tracing/trace.py
2025-10-01 13:03:07 -07:00

579 lines
16 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.
# ==============================================================================
"""package for sglang requests tracing"""
from __future__ import annotations
import logging
import os
import random
import threading
import time
import uuid
from dataclasses import dataclass
from typing import TYPE_CHECKING, Any, Dict, List, Optional
if TYPE_CHECKING:
from sglang.srt.managers.scheduler import Req
logger = logging.getLogger(__name__)
opentelemetry_imported = False
tracing_enabled = False
try:
from opentelemetry import context, propagate, trace
from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.resources import SERVICE_NAME, Resource
from opentelemetry.sdk.trace import TracerProvider, id_generator
from opentelemetry.sdk.trace.export import BatchSpanProcessor
opentelemetry_imported = True
except ImportError:
class id_generator:
class IdGenerator:
pass
logger.info("opentelemetry package is not installed, tracing disabled")
@dataclass
class SglangTraceThreadInfo:
host_id: str
pid: int
thread_label: str
tp_rank: int
dp_rank: int
tracer: trace.Tracer
@dataclass
class SglangTraceSliceContext:
slice_name: str
span: Optional[trace.span.Span] = None
# When True, defers slice_name assignment until trace_slice_end()
anonymous: bool = False
@dataclass
class SglangTraceThreadContext:
thread_info: SglangTraceThreadInfo
cur_slice_stack: List[SglangTraceSliceContext]
thread_span: Optional[trace.span.Span] = None
# Record the most recently completed span as the previous span for the next span to be created.
last_span_context: Optional[trace.span.SpanContext] = None
@dataclass
class SglangTraceReqContext:
rid: str
start_time_ns: int
threads_context: Dict[int, SglangTraceThreadContext]
bootstrap_room: Optional[int] = None
# Indicates whether this instance is a replica from the main process.
# When True, root_span is None and only root_span_context is preserved.
is_copy: bool = False
root_span: Optional[trace.span.Span] = None
root_span_context: Optional[context.Context] = None
@dataclass
class SglangTracePropagateContext:
root_span_context: context.Context
prev_span_context: Optional[trace.span.SpanContext]
def to_dict(self):
carrier: dict[str, str] = {}
context.attach(self.root_span_context)
propagate.inject(carrier)
if self.prev_span_context:
return {
"root_span": carrier,
"prev_span": {
"span_id": self.prev_span_context.span_id,
"trace_id": self.prev_span_context.trace_id,
},
}
else:
return {"root_span": carrier, "prev_span": "None"}
@classmethod
def instance_from_dict(cls, d):
if "root_span" not in d or "prev_span" not in d:
return None
carrier = d["root_span"]
root_span_context = propagate.extract(carrier)
if d["prev_span"] == "None":
prev_span_context = None
else:
prev_span_context = trace.span.SpanContext(
trace_id=d["prev_span"]["trace_id"],
span_id=d["prev_span"]["span_id"],
is_remote=True,
)
return cls(root_span_context, prev_span_context)
class SglangTraceCustomIdGenerator(id_generator.IdGenerator):
"""
The default IdGenerator may produce duplicate trace IDs across multiple TP scheduler processes,
hence a custom IdGenerator is implemented.
"""
def __init__(self):
super().__init__()
self.local_random = random.Random()
self.local_random.seed(time.time())
def generate_trace_id(self) -> int:
return self.local_random.getrandbits(64)
def generate_span_id(self) -> int:
return self.local_random.getrandbits(64)
# global variables
threads_info: Dict[int, SglangTraceThreadInfo] = {}
reqs_context: Dict[str, SglangTraceReqContext] = {}
__get_cur_time_ns = lambda: int(time.time() * 1e9)
def __get_host_id() -> str:
"""
In distributed tracing systems, obtain a unique node identifier
and inject it into all subsequently generated spans
to prevent PID conflicts between threads on different nodes.
"""
if os.path.exists("/etc/machine-id"):
try:
with open("/etc/machine-id", "r") as f:
return f.read().strip()
except:
pass
mac = uuid.getnode()
if mac != 0:
return uuid.UUID(int=mac).hex
return "unknown"
# Should be called by each tracked process.
def process_tracing_init(otlp_endpoint, server_name):
global tracing_enabled
global __get_cur_time_ns
if not opentelemetry_imported:
tracing_enabled = False
return
try:
resource = Resource.create(
attributes={
SERVICE_NAME: server_name,
}
)
tracer_provider = TracerProvider(
resource=resource, id_generator=SglangTraceCustomIdGenerator()
)
processor = BatchSpanProcessor(
OTLPSpanExporter(endpoint=otlp_endpoint, insecure=True)
)
tracer_provider.add_span_processor(processor)
trace.set_tracer_provider(tracer_provider)
except Exception as e:
logger.error(f": initialize opentelemetry error:{e}")
logger.warning("pelease set correct otlp endpoint")
tracing_enabled = False
return
if hasattr(time, "time_ns"):
__get_cur_time_ns = lambda: int(time.time_ns())
tracing_enabled = True
# Should be called by each tracked thread.
def trace_set_thread_info(
thread_label: str, tp_rank: Optional[int] = None, dp_rank: Optional[int] = None
):
if not tracing_enabled:
return
pid = threading.get_native_id()
if pid in threads_info:
return
threads_info[pid] = SglangTraceThreadInfo(
host_id=__get_host_id(),
pid=pid,
thread_label=thread_label,
tp_rank=tp_rank,
dp_rank=dp_rank,
tracer=trace.get_tracer("sglang server"),
)
def __create_thread_context(pid, req_span_context, ts: Optional[int] = None):
if pid not in threads_info:
trace_set_thread_info("unknown")
thread_info = threads_info[pid]
thread_context = SglangTraceThreadContext(
thread_info=thread_info,
cur_slice_stack=[],
)
thread_name = f"{thread_info.thread_label}"
if thread_info.tp_rank is not None:
thread_name += f" [TP {thread_info.tp_rank}] "
thread_name += f"(host:{thread_info.host_id[:8]} | pid:{pid})"
ts = ts or __get_cur_time_ns()
thread_context.thread_span = thread_context.thread_info.tracer.start_span(
name=thread_name,
start_time=ts,
context=req_span_context,
)
if thread_info.tp_rank is not None:
thread_context.thread_span.set_attributes({"tp_rank": thread_info.tp_rank})
thread_context.thread_span.set_attributes(
{
"host_id": thread_info.host_id,
"pid": thread_info.pid,
"thread_label": thread_info.thread_label,
}
)
return thread_context
def trace_get_proc_propagate_context(rid) -> Optional[Dict[str, Any]]:
if not tracing_enabled:
return None
rid = str(rid)
if rid not in reqs_context or not reqs_context[rid].root_span_context:
return None
pid = threading.get_native_id()
prev_span_context = None
thread_context = reqs_context[rid].threads_context[pid]
if thread_context.cur_slice_stack:
cur_slice_info = thread_context.cur_slice_stack[0]
prev_span_context = cur_slice_info.span.get_span_context()
elif thread_context.last_span_context:
prev_span_context = thread_context.last_span_context
trace_context = SglangTracePropagateContext(
reqs_context[rid].root_span_context, prev_span_context
)
return trace_context.to_dict()
def trace_set_proc_propagate_context(rid, trace_context: Optional[Dict[str, Any]]):
if not tracing_enabled:
return
if not trace_context:
return
trace_context = SglangTracePropagateContext.instance_from_dict(trace_context)
if not trace_context:
return
rid = str(rid)
# Create a copy of the request context
if rid not in reqs_context:
reqs_context[rid] = SglangTraceReqContext(
rid=rid,
start_time_ns=__get_cur_time_ns(),
threads_context={},
root_span_context=trace_context.root_span_context,
is_copy=True,
)
pid = threading.get_native_id()
if pid in reqs_context[rid].threads_context:
return
# Create new thread context.
reqs_context[rid].threads_context[pid] = __create_thread_context(
pid,
trace_context.root_span_context,
reqs_context[rid].start_time_ns,
)
reqs_context[rid].threads_context[
pid
].last_span_context = trace_context.prev_span_context
def trace_req_start(
rid: str,
bootstrap_room: Optional[int] = None,
ts: Optional[int] = None,
):
if not tracing_enabled:
return
rid = str(rid)
ts = ts or __get_cur_time_ns()
pid = threading.get_native_id()
if pid not in threads_info:
return
# create req context and root span
reqs_context[rid] = SglangTraceReqContext(
rid=rid,
start_time_ns=ts,
threads_context={},
bootstrap_room=bootstrap_room,
is_copy=False,
)
# Drop the worker_id added by MultiTokenizer
orig_rid = rid.split("_")[-1]
tracer = threads_info[pid].tracer
root_span = tracer.start_span(
name=f"Req {orig_rid[:8]}",
start_time=ts,
)
root_span.set_attributes(
{
"rid": rid,
"bootstrap_room": bootstrap_room if bootstrap_room else "None",
}
)
reqs_context[rid].root_span = root_span
reqs_context[rid].root_span_context = trace.set_span_in_context(root_span)
# create thread context and thread span
reqs_context[rid].threads_context[pid] = __create_thread_context(
pid,
reqs_context[rid].root_span_context,
ts,
)
def trace_req_finish(
rid: str, ts: Optional[int] = None, attrs: Optional[Dict[str, Any]] = None
):
if not tracing_enabled:
return
rid = str(rid)
if rid not in reqs_context:
return
req_context = reqs_context[rid]
ts = ts or __get_cur_time_ns()
# End all unclosed thread spans.
for thread_context in req_context.threads_context.values():
thread_context.thread_span.end(end_time=ts)
if attrs:
req_context.root_span.set_attributes(attrs)
req_context.root_span.end(end_time=ts)
del reqs_context[rid]
def trace_slice_start(
name: str,
rid: str,
ts: Optional[int] = None,
anonymous: bool = False,
):
if not tracing_enabled:
return
rid = str(rid)
if rid not in reqs_context:
return
pid = threading.get_native_id()
if pid not in reqs_context[rid].threads_context:
return
thread_context = reqs_context[rid].threads_context[pid]
ts = ts or __get_cur_time_ns()
slice_info = SglangTraceSliceContext(
slice_name=name,
anonymous=anonymous,
)
# find prev slice
prev_span_context = None
if not thread_context.cur_slice_stack:
if thread_context.last_span_context:
prev_span_context = thread_context.last_span_context
parent_span = thread_context.thread_span
if thread_context.cur_slice_stack:
parent_span = thread_context.cur_slice_stack[-1].span
parent_span_context = trace.set_span_in_context(parent_span)
span = thread_context.thread_info.tracer.start_span(
name=slice_info.slice_name,
start_time=ts,
context=parent_span_context,
)
if prev_span_context:
span.add_link(prev_span_context)
slice_info.span = span
thread_context.cur_slice_stack.append(slice_info)
def trace_slice_end(
name: str,
rid: str,
ts: Optional[int] = None,
attrs: Optional[Dict[str, Any]] = None,
auto_next_anon: bool = False,
thread_finish_flag: bool = False,
):
if not tracing_enabled:
return
rid = str(rid)
if rid not in reqs_context:
return
pid = threading.get_native_id()
if pid not in reqs_context[rid].threads_context:
return
thread_context = reqs_context[rid].threads_context[pid]
if not thread_context.cur_slice_stack:
logger.warning(f"No matching with the SLICE_START event{name} is required.")
return
ts = ts or __get_cur_time_ns()
slice_info = thread_context.cur_slice_stack[-1]
span = slice_info.span
if slice_info.anonymous:
span.update_name(name)
else:
span = slice_info.span
if slice_info.slice_name != name:
span.set_status(trace.Status(trace.StatusCode.ERROR))
logger.warning(f"Slice name mismatch: {name} != {slice_info.slice_name}")
if attrs:
span.set_attributes(attrs)
span.end(end_time=ts)
thread_context.cur_slice_stack.pop()
if len(thread_context.cur_slice_stack) == 0:
thread_context.last_span_context = span.get_span_context()
# If this is the last slice in the thread,
# release the thread context and check whether to release the request context.
if thread_finish_flag:
thread_context.thread_span.end(end_time=ts)
del reqs_context[rid].threads_context[pid]
if reqs_context[rid].is_copy and not reqs_context[rid].threads_context:
del reqs_context[rid]
return
if auto_next_anon:
trace_slice_start("", rid, ts, True)
# alias
trace_slice = trace_slice_end
# Add event to the current slice on the same thread with the same rid.
def trace_event(name: str, rid: str, ts: Optional[int] = None):
if not tracing_enabled:
return
rid = str(rid)
if rid not in reqs_context:
return
pid = threading.get_native_id()
if pid not in reqs_context[rid].threads_context:
return
thread_context = reqs_context[rid].threads_context[pid]
if not thread_context.cur_slice_stack:
logger.warning(f"No slice is currently being traced.")
return
ts = ts or __get_cur_time_ns()
slice_info = thread_context.cur_slice_stack[-1]
slice_info.span.add_event(name=name, timestamp=ts)
# Add attrs to the current slice on the same thread with the same rid.
def trace_slice_add_attr(rid: str, attrs: Dict[str, Any]):
if not tracing_enabled:
return
rid = str(rid)
if rid not in reqs_context:
return
pid = threading.get_native_id()
if pid not in reqs_context[rid].threads_context:
return
thread_context = reqs_context[rid].threads_context[pid]
if not thread_context.cur_slice_stack:
logger.warning(f"No slice is currently being traced.")
return
slice_info = thread_context.cur_slice_stack[-1]
slice_info.span.set_attributes(attrs)
def trace_slice_batch(
name: str,
reqs: List[Req],
):
for req in reqs:
trace_slice(
name,
req.rid,
auto_next_anon=not req.finished(),
thread_finish_flag=req.finished(),
)