sora 370953729b Fix perf stats (wrong import path), per-repeat checkpoints, README
- perf_stats aggregator lives in eval/, not model/: the import failed
  silently and EVERY perf column was empty (not just ttft). Now warns
  on stderr instead of swallowing.
- repeats > 1 get their own checkpoint key (:rep2, :rep3, ...): repeat 2
  previously restored repeat 1's predictions and finished instantly with
  identical scores. rep1 keeps the legacy key (existing checkpoints still
  resume).
- repeats summary: report the MEAN score and aggregate time/tokens over
  ALL runs (was: last run only).
- README: six-benchmark command as the primary example.

Co-Authored-By: Claude <noreply@anthropic.com>
2026-09-11 13:38:04 +00:00

260 lines
10 KiB
Python

"""Multi-endpoint load balancing: one logical model, N local ports.
from evalharness.model.pool import PooledAdapter
from evalharness.model.adapter import resolve_adapter
base = resolve_adapter('openai/http://127.0.0.1:8123/v1?Qwen3-8B')
pool = PooledAdapter([resolve_adapter(f'openai/http://127.0.0.1:{p}/v1?Qwen3-8B')
for p in range(8123, 8131)])
out = await pool.generate(...) # round-robin over instances
Traffic management: round-robin keeps per-endpoint traffic even; backends
that fail repeatedly enter a cool-down window and are skipped until it
expires, so one sick endpoint cannot absorb its share of the load.
"""
import asyncio
import contextlib
import itertools
import time
from typing import Dict, List, Optional
from ..data.sample import ChatMessage
from .adapter import ModelAdapter
from .output import ModelOutput, Usage
class PooledAdapter(ModelAdapter):
"""Round-robin over N equivalent backend instances with health cooling."""
name = 'pool'
COOLDOWN_S = 60.0 # a backend that failed EVERY attempt rests this long
COOLDOWN_AFTER = 2 # consecutive full-pass failures before cooling
def __init__(self, adapters: List[ModelAdapter]):
if not adapters:
raise ValueError('PooledAdapter needs at least one backend')
super().__init__(model=adapters[0].model, api_base=adapters[0].api_base)
self.adapters = adapters
self._cycle = itertools.cycle(range(len(adapters)))
self.usage = Usage()
# request outcome counters (success rate accounting)
self.stats = {'requests': 0, 'ok': 0, 'failed': 0, 'retried': 0}
# per-backend health: consecutive_failures, cooling_until, per-endpoint counts
self._health = [{ 'fails': 0, 'until': 0.0, 'ok': 0, 'req': 0}
for _ in adapters]
# adaptive per-endpoint concurrency gates (AIMD over /metrics signals)
self._gates = [AdaptiveGate(a) for a in adapters]
def _next(self) -> ModelAdapter:
"""Round-robin, skipping endpoints inside their cool-down window."""
n = len(self.adapters)
now = time.time()
for _ in range(n):
i = next(self._cycle)
h = self._health[i]
if h['until'] <= now or all(x['until'] <= now for x in self._health):
self._health[i]['req'] += 1
return self.adapters[i]
# everything cooling: take the next anyway (better to try than stall)
i = next(self._cycle)
self._health[i]['req'] += 1
return self.adapters[i]
def _mark(self, adapter: ModelAdapter, ok: bool) -> None:
try:
i = self.adapters.index(adapter)
except ValueError:
return
h = self._health[i]
if ok:
h['fails'] = 0
h['until'] = 0.0
h['ok'] += 1
else:
h['fails'] += 1
if h['fails'] >= self.COOLDOWN_AFTER:
h['until'] = time.time() + self.COOLDOWN_S
h['fails'] = 0
def request_stats(self) -> Dict[str, float]:
"""Success-rate + per-endpoint traffic view (load-balance audit)."""
n = self.stats['requests']
out = {
'requests': n,
'success_rate': self.stats['ok'] / n if n else 0.0,
'retry_rate': self.stats['retried'] / n if n else 0.0,
'failure_rate': self.stats['failed'] / n if n else 0.0,
}
for i, (a, h) in enumerate(zip(self.adapters, self._health)):
tag = a.api_base.rsplit('//', 1)[-1].replace('/', '_')
out[f'ep{i}_{tag}_reqs'] = h['req']
out[f'ep{i}_{tag}_ok'] = h['ok']
if i < len(self._gates):
for k, v in self._gates[i].report().items():
out[f'ep{i}_{tag}_{k}'] = v
return out
async def generate(self, messages: List[ChatMessage],
tools: Optional[list] = None, **kw) -> ModelOutput:
last_exc = None
self.stats['requests'] += 1
for _ in range(len(self.adapters)): # try each instance once
adapter = self._next()
try:
i = self.adapters.index(adapter)
await self._gates[i].acquire()
try:
out = await adapter.generate(messages, tools=tools, **kw)
finally:
self._gates[i].release(True)
self.usage = self.usage + out.usage
self.stats['ok'] += 1
self._mark(adapter, True)
if out.usage.retries:
self.stats['retried'] += 1
return out
except Exception as e: # dead/overloaded instance -> next
last_exc = e
self._mark(adapter, False)
with contextlib.suppress(ValueError):
self._gates[self.adapters.index(adapter)].release(False)
# 4xx (e.g. 400 overloaded) still worth trying ANOTHER instance:
# one backend's state can differ from the rest
continue
self.stats['failed'] += 1
raise last_exc
async def close(self) -> None:
for a in self.adapters:
await a.close()
for g in self._gates:
g.stop()
class AdaptiveGate:
"""Per-endpoint adaptive concurrency limiter (AIMD + server signals).
Goal: keep the backend SATURATED (high XPU util / throughput) without
pushing it over the cliff (500s / child crashes). Signals:
- server /metrics: num_queue_reqs > 0 means WE are pushing too hard
for the current mix; idle (no queue, low running) means room to grow
- request failures: multiplicative decrease (survive first)
Control law (classic AIMD):
+1 concurrency per probe interval when the endpoint looks underfed
-1 when the server reports a queue (gentle)
x0.7 on any failed request (fast backoff), floor at LO
Purely additive to PooledAdapter: one gate per backend, no caller change.
"""
LO = 2 # never go below: progress beats perfection
HI = 96 # sane ceiling for one endpoint
PROBE_S = 5.0 # metrics probe interval
def __init__(self, adapter: ModelAdapter):
self.adapter = adapter
self.limit = 8.0 # float for smooth x0.7; compare with int()
self._inflight = 0
self._cond: Optional[asyncio.Condition] = None
self._task: Optional[asyncio.Task] = None
self._stopped = False
self.stats = {'probe': 0, 'ramp': 0, 'hold_queue': 0, 'backoff_fail': 0,
'backoff_queue': 0}
# ---- gate semantics ----
async def acquire(self) -> None:
if self._cond is None: # lazy init in the running loop
self._cond = asyncio.Condition()
self._task = asyncio.get_event_loop().create_task(self._probe_loop())
while self._inflight >= max(1, int(self.limit)):
await self._cond.acquire()
try:
await self._cond.wait()
finally:
self._cond.release()
self._inflight += 1
def release(self, ok: bool) -> None:
self._inflight = max(0, self._inflight - 1)
if not ok: # multiplicative decrease -- survival first
before = self.limit
self.limit = max(self.LO, self.limit * 0.7)
if before != self.limit:
self.stats['backoff_fail'] += 1
self._wake()
def _wake(self) -> None:
if self._cond is not None:
# fire-and-forget notify (loop may not be ours -- best effort)
try:
fut = asyncio.ensure_future(self._notify_all())
fut.add_done_callback(lambda f: None)
except RuntimeError:
pass
async def _notify_all(self) -> None:
async with self._cond:
self._cond.notify_all()
# ---- server-signal probe ----
async def _probe_once(self) -> None:
import urllib.request
url = f'{self.adapter.api_base.rstrip("/")}/metrics'
try:
with urllib.request.urlopen(url, timeout=4) as resp:
text = resp.read().decode('utf-8', 'ignore')
except Exception:
return # no metrics (or busy): hold current limit
running = queue = None
for line in text.splitlines():
if line.startswith('sglang:num_running_reqs'):
running = float(line.rsplit(' ', 1)[-1])
elif line.startswith('sglang:num_queue_reqs'):
queue = float(line.rsplit(' ', 1)[-1])
self.stats['probe'] += 1
if queue is None and running is None:
return
if queue is not None and queue >= 2:
# server is queuing OUR excess: gentle additive decrease
self.limit = max(self.LO, self.limit - 1)
self.stats['backoff_queue'] += 1
elif (queue or 0) == 0 and (running is None or running < max(2, int(self.limit))):
# underfed: no queue and running below our own cap -> ramp up
self.limit = min(self.HI, self.limit + 1)
self.stats['ramp'] += 1
else:
self.stats['hold_queue'] += 1
self._wake()
async def _probe_loop(self) -> None:
import contextlib
while not self._stopped:
with contextlib.suppress(Exception):
await self._probe_once()
await asyncio.sleep(self.PROBE_S)
def stop(self) -> None:
self._stopped = True
if self._task is not None:
self._task.cancel()
def report(self) -> Dict[str, float]:
return {'limit': max(1, int(self.limit)), 'inflight': self._inflight,
**{f'gate_{k}': v for k, v in self.stats.items()}}
def pooled(specs: List[str], api_key: str = '') -> PooledAdapter:
"""['openai/http://127.0.0.1:8123/v1?M', ...] -> PooledAdapter.
api_key: explicit key applied to EVERY member (two-key setups should
build two pools, or use env resolution per host)."""
from .adapter import resolve_adapter
members = [resolve_adapter(s) for s in specs]
if api_key:
for m in members:
m.api_key = api_key
return PooledAdapter(members)