What Is a Goroutine Leak and How to Prevent It

Concurrency
2026-04-17T12:05:42+00:00
A goroutine leak is a non-terminating background task that consumes resources, prevented by ensuring every goroutine has a clear exit condition via context cancellation or channel closure.

A goroutine leak occurs when a goroutine is started but never terminates, holding onto memory and CPU resources indefinitely. This usually happens when a goroutine blocks forever on a channel send or receive with no corresponding operation, or when a loop lacks an exit condition. To prevent leaks, ensure every go statement has a clear termination path, often by using context.Context to signal cancellation or by closing channels to unblock waiting receivers.

ctx, cancel := context.WithCancel(context.Background())

// Start goroutine with context
wg.Add(1)
go func() {
    defer wg.Done()
    for {
        select {
        case <-ctx.Done():
            return // Exit immediately on cancellation
        case data := <-inputChan:
            process(data)
        }
    }
}()

// Later: cancel to stop the goroutine
cancel()
wg.Wait()