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Update java-concurrent-questions-01.md #1783

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Expand Up @@ -131,7 +131,7 @@ Java 线程在运行的生命周期中的指定时刻只可能处于下面 6 种

由上图可以看出：线程创建之后它将处于 **NEW（新建）** 状态，调用 `start()` 方法后开始运行，线程这时候处于 **READY（可运行）** 状态。可运行状态的线程获得了 CPU 时间片（timeslice）后就处于 **RUNNING（运行）** 状态。

> 在操作系统中层面线程有 READY 和 RUNNING 状态，而在 JVM 层面只能看到 RUNNABLE 状态（图源：[HowToDoInJava](https://howtodoinJava.com/ "HowToDoInJava")：[Java Thread Life Cycle and Thread States](https://howtodoinJava.com/Java/multi-threading/Java-thread-life-cycle-and-thread-states/ "Java Thread Life Cycle and Thread States")），所以 Java 系统一般将这两个状态统称为 **RUNNABLE（运行中）** 状态 。
> 在操作系统层面，线程有 READY 和 RUNNING 状态；而在 JVM 层面，只能看到 RUNNABLE 状态（图源：[HowToDoInJava](https://howtodoinJava.com/ "HowToDoInJava")：[Java Thread Life Cycle and Thread States](https://howtodoinJava.com/Java/multi-threading/Java-thread-life-cycle-and-thread-states/ "Java Thread Life Cycle and Thread States")），所以 Java 系统一般将这两个状态统称为 **RUNNABLE（运行中）** 状态 。
>
> **为什么 JVM 没有区分这两种状态呢？** （摘自：[java线程运行怎么有第六种状态？ - Dawell的回答](https://www.zhihu.com/question/56494969/answer/154053599) ） 现在的<b>时分</b>（time-sharing）<b>多任务</b>（multi-task）操作系统架构通常都是用所谓的“<b>时间分片</b>（time quantum or time slice）”方式进行<b>抢占式</b>（preemptive）轮转调度（round-robin式）。这个时间分片通常是很小的，一个线程一次最多只能在 CPU 上运行比如 10-20ms 的时间（此时处于 running 状态），也即大概只有 0.01 秒这一量级，时间片用后就要被切换下来放入调度队列的末尾等待再次调度。（也即回到 ready 状态）。线程切换的如此之快，区分这两种状态就没什么意义了。

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