"ps -o rss,drs,trs,vsz,sz" - Process Status Options

Linux Tutorials - Herong's Tutorial Examples

∟"ps -o rss,drs,trs,vsz,sz" - Process Status Options

This section provides a tutorial on how to 'ps -o rss,drs,trs,vsz,sz' command to report memory usage of each running process.

If you want to know memory usage at the process level, you can use the "ps -o" command option with "rss,drs,trs,vsz,sz" output fields. Here are some examples:

1. The following command displays all running processes with memory usage fields:

herong$ ps -e -o pid,euser,%cpu,%mem,rss,drs,trs,sz,vsz,comm

 PID EUSER %CPU %MEM  RSS    DRS TRS    SZ    VSZ COMMAND
   1 root   0.0  0.0 7376 241488   0 60372 241488 systemd
   2 root   0.0  0.0    0      0   0     0      0 kthreadd
   3 root   0.0  0.0    0      0   0     0      0 rcu_gp
   4 root   0.0  0.0    0      0   0     0      0 rcu_par_gp
...
1515 root   0.0  0.0  480  50400   0 12600  50400 smartd
1520 root   0.0  0.0  480 219444   0 54861 219444 sssd
1521 rtkit  0.0  0.0   28 202848   0 50712 202848 rtkit-daemon
1522 dbus   0.0  0.0 3228  93028   0 23257  93028 dbus-daemon
...

The memory usage fields in the output are:

%MEM - Percentage of physical memory used by the process.
RSS (Resident Set Size) - RAM used by the process (exclusively and shared memory) in KiB.
DRS (Data Resident Set) - Physical memory used by the process as data area in KiB.
TRS (Text Resident Set) - Physical memory used by the process as program code area in KiB.
SZ - Total physical memory used by the process in KiB, including text (program code), data and stack areas.
VSZ (Virtual memory size) - Virtual memory used by the process in KiB.

2. The "--sort=vsz" option sorts the output by the virtual memory usage.

herong$ ps -e -o pid,euser,%mem,rss,drs,trs,sz,vsz,comm --sort=vsz

  PID EUSER  %MEM  RSS   DRS  TRS   SZ   VSZ COMMAND
    2 root    0.0    0     0    0    0     0 kthreadd
    3 root    0.0    0     0    0    0     0 rcu_gp
    4 root    0.0    0     0    0    0     0 rcu_par_gp
    8 root    0.0    0     0    0    0     0 mm_percpu_wq
...
58989 herong  0.0 2232  9731   36 2442  9768 more
 1532 root    0.0    4 17788    0 4447 17788 mcelog
58491 herong  0.0 5332 24853 1054 6477 25908 bash
 1559 root    0.0 1592 26836    0 6709 26836 ksmtuned
...

3. The "--sort=-vsz" option sorts the output by the virtual memory usage in descending order.

herong$ ps -e -o pid,euser,%mem,rss,drs,trs,sz,vsz,comm --sort=-vsz

  PID EUSER   %MEM    RSS     DRS TRS      SZ     VSZ COMMAND
 3399 gdm      0.3  55744 8618344   0 2154586 8618344 gnome-shell
 1998 mysql    4.1 645924 3439668   0  859917 3439668 mysqld
 2498 gdm      0.0   7476 3089652   0  772413 3089652 Xorg
91677 apache   0.1  16856 2801800   0  700450 2801800 httpd
92412 apache   0.0  14176 2605120   0  651280 2605120 httpd
 1517 polkitd  0.0   2552 2064372   0  516093 2064372 polkitd
...