[workqueue] Question about interruptibleQueue

General Discussions
1

client-go workqueue provides a non-interruptible queue that works in the following pattern

func Run(ctx context.Context, queue workqueue.RateLimitingInterface) {
    for i := 0; i < 4; i++ {
        go wait.Until(func() { worker(queue) }, time.Second, ctx.Done())
    }

    go fakeResourceInformer(ctx, queue)

    <-ctx.Done()
    
    queue.ShutDown()
}

func worker(queue workqueue.RateLimitingInterface) {
    for {
        item, shutdown := queue.Get()
        if shutdown {
            return
        }
        if item != nil {
            defer queue.Done(item)
            if err := processItem(item); err != nil {
                queue.AddRateLimited(item)
            }
        }
    }
}

However, if I want to shut down a worker goroutine without shutting down the queue Dynamic controller scaling · Issue #2576 · kubernetes-sigs/controller-runtime · GitHub, it may not be easy since the worker could be stuck at the blocking queue.Get. My question is, what is the best practice to stop a running worker to reduce resource usage? Why doesn’t the official provide a nonblocking queue.Get(ctx) or something interruptible?