// transition tasks
func (t *transitionState) UpdateWorkers(n int) {
	t.mu.Lock()
	defer t.mu.Unlock()
	if t.objAPI == nil { // Init hasn't been called yet.
		return
	}
	t.updateWorkers(n)
}

func (t *transitionState) updateWorkers(n int) {
	for t.numWorkers < n {
		go t.worker(t.objAPI)
		t.numWorkers++
	}

	for t.numWorkers > n {