How to Implement the Semaphore Pattern in Go

Concurrency

2026-04-17T12:05:42+00:00

Implement the semaphore pattern in Go using the golang.org/x/sync/semaphore package to limit concurrent operations.

Use golang.org/x/sync/semaphore to create a weighted semaphore that limits concurrent operations. Import the package, create a new semaphore with NewWeighted, and call Acquire before your critical section and Release after.

import "golang.org/x/sync/semaphore"

sem := semaphore.NewWeighted(3)
if err := sem.Acquire(context.Background(), 1); err != nil {
    // handle error
}
defer sem.Release(1)
// critical section