timewheel启动了很久，新插入一个定时器直接就过期

[tangeping]

currentTime 只有在advanceClock中更新。假如 timewheel开了很久了，bucket 中没有定时器，新插入一个定时器，addOrRun读到currentTime 是不是直接就过期了?

func (tw *TimingWheel) advanceClock(expiration int64) {
	currentTime := atomic.LoadInt64(&tw.currentTime)
	if expiration >= currentTime+tw.tick {
		currentTime = truncate(expiration, tw.tick)
		atomic.StoreInt64(&tw.currentTime, currentTime)

		// Try to advance the clock of the overflow wheel if present
		overflowWheel := atomic.LoadPointer(&tw.overflowWheel)
		if overflowWheel != nil {
			(*TimingWheel)(overflowWheel).advanceClock(currentTime)
		}
	}
}

@RussellLuo

[ch0ngsheng]

时间轮的currentTime向前推进，是由DelayQueue中的堆顶元素过期的事件触发的。没有bucket到期就不会更新currentTime。