go resource_error ai_generated true

goroutine leak: N goroutines blocked in chan send (detected via pprof)

ID: go/goroutine-leak-blocked-send

Also available as: JSON · Markdown · 中文
80%Fix Rate
87%Confidence
0Evidence
2024-08-14First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
1.0+ active — — —

Root Cause

Goroutines were spawned to send on an unbuffered or full channel whose receiver stopped reading, so they block forever and accumulate.

generic

中文

启动的 goroutine 向无缓冲或已满的 channel 发送数据，但接收方已停止读取，导致它们永久阻塞并不断累积。

Workarounds

  1. 95% success 
    select {
case ch <- v:
case <-ctx.Done():
    return
}
  2. 90% success 
    jobs := make(chan Job, 128)
for i := 0; i < runtime.NumCPU(); i++ {
    go func() { for j := range jobs { process(j) } }()
}

Dead Ends

Common approaches that don't work:

  1. 95% fail

    Blocked goroutines are not CPU-bound; more CPUs do not unblock them and memory keeps growing.

  2. 90% fail

    GC does not collect goroutines blocked on channels; they remain reachable from the scheduler.