// So we will be simply closing the channel, and synchronizing on the WaitGroup.
		stopCh:           stopCh,
		clock:            config.Clock,
		timer:            time.NewTimer(time.Duration(0)),
		bookmarkWatchers: newTimeBucketWatchers(config.Clock, defaultBookmarkFrequency),
	}

	// Ensure that timer is stopped.
	if !cacher.timer.Stop() {

		// time.
		r := rand.New(rand.NewSource(time.Now().UnixNano()))
		randSleepFor := func() time.Duration {
			return 5*time.Second + time.Duration(float64(5*time.Second)*r.Float64())
		}

		timer := time.NewTimer(randSleepFor())
		defer timer.Stop()

		var (
			quit     bool
			traceMsg string
		)

		for {
			select {
			case rebalErr := <-doneCh:
				quit = true
				now := time.Now()

			err = wrappedError{
				prefix: "exec: canceling Cmd",
				err:    interruptErr,
			}
		}
	}
	if c.WaitDelay == 0 {
		resultc <- ctxResult{err: err}
		return
	}

	timer := time.NewTimer(c.WaitDelay)
	select {
	case resultc <- ctxResult{err: err, timer: timer}:
		// c.Process.Wait returned and we've handed the timer off to c.Wait.
		// It will take care of goroutine shutdown from here.
		return

	// Start the main racer.
	primaryCtx, primaryCancel := context.WithCancel(ctx)
	defer primaryCancel()
	go startRacer(primaryCtx, true)

	// Start the timer for the fallback racer.
	fallbackTimer := time.NewTimer(sd.fallbackDelay())
	defer fallbackTimer.Stop()

	for {
		select {
		case <-fallbackTimer.C:
			fallbackCtx, fallbackCancel := context.WithCancel(ctx)
			defer fallbackCancel()

			Node:                   req.Node,
			TypeUrl:                req.TypeUrl,
			ResourceNamesSubscribe: req.ResourceNames,
		})
	} else {
		connection.sendRequest(req)
	}

	delay := time.NewTimer(timeout)
	defer delay.Stop()

	// Wait for expected response or timeout
	for {
		select {
		case res := <-p.tapResponseChannel:
			if res.TypeUrl == req.TypeUrl {
				return res, nil
			}

	// resourceVersion=0 is the most common case.
	if resourceVersion > 0 {
		go func() {
			// Wake us up when the time limit has expired.  The docs
			// promise that time.After (well, NewTimer, which it calls)
			// will wait *at least* the duration given. Since this go
			// routine starts sometime after we record the start time, and
			// it will wake up the loop below sometime after the broadcast,

// and that we also don't panic.
func TestConcurrentTimerReset(t *testing.T) {
	const goroutines = 8
	const tries = 1000
	var wg sync.WaitGroup
	wg.Add(goroutines)
	timer := NewTimer(Hour)
	for i := 0; i < goroutines; i++ {
		go func(i int) {
			defer wg.Done()
			for j := 0; j < tries; j++ {
				timer.Reset(Hour + Duration(i*j))
			}
		}(i)
	}
	wg.Wait()
}

		var buf [1]byte
		var rres readResult
		rres.n, rres.err = body.Read(buf[:])
		if rres.n == 1 {
			rres.b = buf[0]
		}
		t.ByteReadCh <- rres
		close(t.ByteReadCh)
	}(t.Body)
	timer := time.NewTimer(200 * time.Millisecond)
	select {
	case rres := <-t.ByteReadCh:
		timer.Stop()
		if rres.n == 0 && rres.err == io.EOF {
			// It was empty.
			t.Body = nil
			t.ContentLength = 0
		} else if rres.n == 1 {

	wc.upperBoundCapacity = max(capacity, defaultUpperBoundCapacity)

	return wc
}

type immediateTickerFactory struct{}

func (t *immediateTickerFactory) NewTimer(d time.Duration) clock.Timer {
	timer := immediateTicker{
		c: make(chan time.Time),
	}
	timer.Reset(d)
	return &timer
}

type immediateTicker struct {
	c chan time.Time
}

			if len(args) != 1 {
				return nil, ErrUsage
			}

			d, err := time.ParseDuration(args[0])
			if err != nil {
				return nil, err
			}

			timer := time.NewTimer(d)
			wait := func(s *State) (stdout, stderr string, err error) {
				ctx := s.Context()
				select {
				case <-ctx.Done():
					timer.Stop()
					return "", "", ctx.Err()
				case <-timer.C: