Showing posts with label how to check the process states and its information in linux. Show all posts
Showing posts with label how to check the process states and its information in linux. Show all posts

Wednesday, September 12, 2012

Check the Process id and Process states

 [root@crs2 ~]# ps -aux | less


USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1  0.0  0.0   2040   632 ?        Ss   09:30   0:00 init [5]     
                    
root         2  0.0  0.0      0     0 ?        S    09:30   0:00 [migration/0]
root         3  0.0  0.0      0     0 ?        SN   09:30   0:00 [ksoftirqd/0]
root         4  0.0  0.0      0     0 ?        S    09:30   0:00 [watchdog/0]
root         5  0.0  0.0      0     0 ?        S<   09:30   0:00 [events/0]
root         6  0.0  0.0      0     0 ?        S<   09:30   0:00 [khelper]
root         7  0.0  0.0      0     0 ?        S<   09:30   0:00 [kthread]
root        10  0.0  0.0      0     0 ?        S<   09:30   0:00 [kblockd/0]
root        11  0.0  0.0      0     0 ?        S<   09:30   0:00 [kacpid]
root       180  0.0  0.0      0     0 ?        S<   09:30   0:00 [cqueue/0]
root       183  0.0  0.0      0     0 ?        S<   09:30   0:00 [khubd]
root       185  0.0  0.0      0     0 ?        S<   09:30   0:00 [kseriod]
root       249  0.0  0.0      0     0 ?        S    09:30   0:00 [pdflush]
root       250  0.0  0.0      0     0 ?        S    09:30   0:00 [pdflush]
:



You can check the process id and states of process using the below command and syntax.

[root@crs2 ~]# ps -C init -o pid=,cmd,stat
      CMD                         STAT
    1 init [5]                    Ss

[root@crs2 ~]# ps -C firefox -o pid=,cmd,stat
      CMD                         STAT
 6666 /bin/sh /usr/lib/firefox-1. S

 Processes states that ps indicate are:

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.

< 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