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进程的睡眠模式类型

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进程的睡眠模式类型

我在排查为什么每次 oracle 进程被终止时我们的服务器都会宕机时遇到了这个问题。我列出了在服务器上运行的 oracle 进程ps aux | grep oracle，以下是输出：

oracle   21739  0.0  0.0 165068 17488 ?        Ssl  Oct14   0:18 /apps/11203/grid/bin/mdnsd.bin
oracle   21759  0.1  0.0 176556 25672 ?        Ssl  Oct14   1:14 /apps/11203/grid/bin/gpnpd.bin
oracle   21772  0.9  0.0 249528 31320 ?        Sl   Oct14   8:04 /apps/11203/grid/bin/gipcd.bin
oracle   21830  1.1  0.0 265760 115908 ?       SLl  Oct14   9:54 /apps/11203/grid/bin/ocssd.bin
oracle   21969  0.2  0.0 268648 29148 ?        Ssl  Oct14   2:10 /apps/11203/grid/bin/evmd.bin
oracle   22246  0.0  0.0  92420 13024 ?        S    Oct14    0:00 /apps/11203/grid/bin/evmlogger.bin -o /apps/11203/grid/evm/log/evmlogger.info -l /apps/11203/grid/evm/log/evmlogger.log

是的，所有这些进程都在睡眠，从它们的状态代码来看，有不同类型的睡眠 - Ssl, Sl, SLl。我在谷歌上搜索了不同类型的进程睡眠，但只找到了有关磁盘睡眠、可中断和不可中断睡眠的信息。我没有看到任何关于各种睡眠的子状态的信息Ssl, Sl, SLl。这里有人知道 SsL、Sl 和 SLl 有什么不同吗？

根据用户“chaos”的评论，我将这些状态确定为：

Ssl - sleeping, is a session loader and multi-threaded. 
SL - sleeping, has pages locked into memory
Sl - sleeping, and the process is multi-threaded

那么这些是什么意思呢？处于“SL - 睡眠状态，已将页面锁定到内存中”的进程是否正在使用内存？如果有很多“SL”进程，它们是否会占用其他进程的内存？

（所有这些进程的父进程都是init，如果这有什么区别的话）。

答案1

这是来自ps联机帮助页：

进程状态代码：以下是 s、stat 和状态输出说明符（标题“STAT”或“S”）将显示的不同值，用于描述进程的状态：

   D    uninterruptible sleep (usually IO)
   R    running or runnable (on run queue)
   S    interruptible sleep (waiting for an event to complete)
   T    stopped, either by a job control signal or because it is being traced.
   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.

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