zrlw opened a new issue #8949:
URL: https://github.com/apache/dubbo/issues/8949
### Environment
* Dubbo version: 3.0 / master
1. waitForNextTick想法有点多
```
final long currentTime = System.nanoTime() - startTime; <==
startTime是初始化HashedWheelTimer的时间，currentTime是时间差，应用程序持续运行时间只要不超过292年，currentTime这个值都不会小于0。即使System.nanoTime()返回的当前时间超过LONG最大值变成了负数，它和startTime之间的纳秒时间差只要不超过2^63次方-1，currentTime就不会变成负值。
long sleepTimeMs = (deadline - currentTime + 999999) /
1000000;
if (sleepTimeMs <= 0) {
if (currentTime == Long.MIN_VALUE) {
<==
Long.MIN_VALUE是-2^63，程序要持续运行262年之后才有遇到它的机会；返回负值也有问题，调用waitForNextTick的代码只认返回值大于0的情况。
return -Long.MAX_VALUE;
} else {
return currentTime;
}
}
```
2.
HashedWheelTimer的maxPendingTimeouts可以任意设置，但实际情况是超过cpu核数时，超时机制就会混乱起来，原因是sleep的线程太多了，sleep时间到了也抢不到cpu。
HashedWheelTimerTest的createTaskTest测试方法在4核windows机器上跑单元测试，多半失败：
```
Thread.sleep(100); 《==
实测发现执行expireTimeouts的线程很少能在1秒内抢到cpu，所以这里的100ms是想当然了
Assertions.assertTrue(timeout.isExpired());
timer.stop();
```
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