python runtime_error ai_generated true

asyncio.exceptions.TimeoutError: semaphore could not be acquired within timeout

ID: python/asyncio-semaphore-timeout

Also available as: JSON · Markdown · 中文
80%Fix Rate
82%Confidence
0Evidence
2024-07-08First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.8 active — — —
3.9 active — — —
3.10 active — — —

Root Cause

Using asyncio.wait_for() on a semaphore acquire() that times out due to high contention.

generic

中文

在高竞争情况下，对信号量acquire()使用asyncio.wait_for()导致超时。

Workarounds

  1. 85% success 
    async with asyncio.timeout(5): await sem.acquire()
  2. 80% success 
    for i in range(3): try: await asyncio.wait_for(sem.acquire(), 1); break except TimeoutError: pass

Dead Ends

Common approaches that don't work:

  1. 60% fail

    May still fail under heavy load; doesn't address root cause.

  2. 70% fail

    Leads to resource exhaustion and potential system instability.