ps

From Initq

In most Unix-like operating systems, ps is a program that displays the currently running processes. A related Unix utility named top provides a real-time view of the running processes.

Examples

An example of the ps command is:

tux ~ # ps
  PID TTY          TIME CMD
 7431 pts/0    00:00:00 su
 7434 pts/0    00:00:00 bash
18585 pts/0    00:00:00 ps

The ps command can also be used in conjunction with the grep command to find information about one process, such as its process id. An example of this is:

tux ~ # ps -A | grep firefox-bin
11778 ?        02:40:08 firefox-bin
11779 ?        00:00:00 firefox-bin

Options

ps has many options. On operating systems that support the UNIX and POSIX standards, ps is commonly run with the options -ef, where "-e" selects every process and "-f" chooses the "full" output format. Another common option on these systems is -l, which specifies the "long" output format.

Most systems derived from BSD fail to accept the POSIX and UNIX standard options because of historical conflicts (for example, the "e" or "-e" option will cause environment variabless to be displayed). On such systems, ps is commonly used with the non-standard options aux, where "a" lists all processes on a terminal, including those of other users, "x" lists all processes without controlling terminals and "u" adds the controlling user for each process. Note that, for maximum compatibility when using this syntax, there is no "-" in front of the "aux". Also you can add 'www' after aux, like "ps auxwww" for complete information about the process including all params.

Flags

• u display user-oriented format
• -u user
• --forest three structure
• w wide
• a all

[alibaba@ohnonono junk]$ ps u U alibaba
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
alibaba   7596  0.0  0.0   8996  1612 ?        S    12:15   0:00 sshd: alibaba@pts/1
alibaba   7597  0.0  0.0   4504  1436 pts/1    Ss   12:15   0:00 -bash
alibaba   9152  0.0  0.0   4228   936 pts/1    R+   16:36   0:00 ps u U alibaba
alibaba  29294  0.0  0.0   4504  1404 pts/3    S+   May24   0:00 -bash
alibaba  29921  0.0  0.0   4500  1400 pts/4    S+   May24   0:00 -bash

If you want to look at just the command column then

• ps -xo comm

if you want to look at command and memory then

• ps -xo comm,pmem | sort +1n | uniq | tac

See a particular users processes

You can use the -fu flag followed by the username.

-bash-3.00$ ps -fu jbadmin
     UID   PID  PPID   C    STIME TTY         TIME CMD
 jbadmin 29780 22043   0 09:32:33 pts/2       0:00 ps -fu jbadmin
 jbadmin 22041 22038   0   Oct 27 ?           0:00 /usr/lib/ssh/sshd
 jbadmin 29777 29764   0 09:17:38 pts/2       2:07 /opt/apptricity/jdk-1_5_0_09-solaris-i586/jdk1.5.0
 jbadmin 29764     1   0 09:17:37 pts/2       0:00 /bin/sh /opt/apptricity/jboss-4.2.3/bin/runapptricity40.sh 
 jbadmin 22043 22041   0   Oct 27 pts/2       0:00 -bash