Linux下巧用ps得到運行線程個數和線程啟動時間

Linux進程運行了很久，怎麼能夠得到某一進程所有的線程個數並且得到它們的啟動時間，除了讀取/proc信息之外，我們可以使用ps簡單的達到目的。

ps max -o lstart,lwp,pid,nlwp,cmd

lstart STARTED time the command started.
nlwp NLWP number of lwps (threads) in the process. (alias thcount).
lwp LWP lwp (light weight process, or thread) ID of the lwp being reported.
(alias spid, tid).

BONO11-0-0-1:/root-# ps max -o %mem,lstart,lwp,pid,nlwp,cmd

%MEM STARTED LWP PID NLWP CMD
0.0 Fri Nov 11 13:25:29 2011 - 1 1 init [3]
- Fri Nov 11 13:25:29 2011 1 - - -
0.0 Fri Nov 11 13:25:29 2011 - 2 1 [migration/0]
- Fri Nov 11 13:25:29 2011 2 - - -
0.0 Fri Nov 11 13:25:29 2011 - 3 1 [ksoftirqd/0]
- Fri Nov 11 13:25:29 2011 3 - - -

...

0.0 Fri Nov 11 13:50:46 2011 - 31012 8 /opt/proxy/bin/http_stack Http Stack benchHttp__asr_1_h - Fri Nov 11 13:50:46 2011 31012 - - -
- Fri Nov 11 13:50:46 2011 31016 - - -
- Fri Nov 11 13:50:46 2011 31018 - - -
- Fri Nov 11 13:50:46 2011 31019 - - -
- Fri Nov 11 13:50:47 2011 31855 - - -
- Fri Nov 11 13:50:47 2011 31856 - - -
- Fri Nov 11 13:50:47 2011 31857 - - -
- Fri Nov 11 13:50:47 2011 31926 - - -
0.0 Fri Nov 11 17:14:19 2011 - 31272 1 sshd: root@notty
- Fri Nov 11 17:14:19 2011 31272 - - -

我們可以驗證正好有8個task.

BONO11-0-0-1:/root-# ls /proc/31012/task/
31012 31016 31018 31019 31855 31856 31857 31926