PS 查看进行状态

原文：https://blog.csdn.net/lyndon_li/article/details/114295654

ps 查看进行状态有如下几种：

...
PROCESS STATE CODES
       Here are the different values that the s, stat and state output specifiers (header "STAT" or "S") will display to describe the state of a process:

               D    uninterruptible sleep (usually IO)
               I    Idle kernel thread
               R    running or runnable (on run queue)
               S    interruptible sleep (waiting for an event to complete)
               T    stopped by job control signal
               t    stopped by debugger during the tracing
               W    paging (not valid since the 2.6.xx kernel)
               X    dead (should never be seen)
               Z    defunct ("zombie") process, terminated but not reaped by
                    its parent

       For BSD formats and when the stat keyword is used, additional characters may be displayed:

               <    high-priority (not nice to other users)
               N    low-priority (nice to other users)
               L    has pages locked into memory (for real-time and custom IO)
               s    is a session leader
               l    is multi-threaded (using CLONE_THREAD, like NPTL pthreads
                    do)
               +    is in the foreground process group

               D (TASK_UNINTERRUPTIBLE)        不可中断的睡眠状态
               R (TASK_RUNNING)                正在运行，或在队列中的进程
               S (TASK_INTERRUPTIBLE)          可中断的睡眠状态
               T (TASK_STOPPED)                停止状态
               t (TASK_TRACED)                 被跟踪状态
               Z (TASK_DEAD - EXIT_ZOMBIE)     退出状态，但没被父进程收尸，成为僵尸状态
               W                               进入内存交换（从内核2.6开始无效）
               X (TASK_DEAD - EXIT_DEAD)       退出状态，进程即将被销毁


               <    高优先级
               N    低优先级
               L    有些页被锁进内存
               s    包含子进程
               +    位于前台的进程组；
               l    多线程，克隆线程  multi-threaded (using CLONE_THREAD, like NPTL pthreads do)

注：

TASK_INTERRUPTIBLE 和TASK_UNINTERRUPTIBLE 的区别

TASK_INTERRUPTIBLE：是可以被信号和wake_up()唤醒的，当信号到来时，进程会被设置为可运行。

TASK_UNINTERRUPTIBLE：只能被wake_up()唤醒。