ps -- process status
ps [-aCcefHhjlmrSTuvwXxZ] [-O fmt | -o fmt] [-G gid[,gid...]] [-M core] [-N system] [-p pid[,pid...]] [-t tty[,tty...]] [-U user[,user...]] ps [-L]
The ps utility displays a header line, followed by lines containing information about all of your processes that have controlling terminals. A different set of processes can be selected for display by using any combination of the -a, -G, -p, -T, -t, and -U options. If more than one of these options are given, then ps will select all processes which are matched by at least one of the given options. For the processes which have been selected for display, ps will usually display one line per process. The -H option may result in multiple out- put lines (one line per thread) for some processes. By default all of these output lines are sorted first by controlling terminal, then by process ID. The -m, -r, -u, and -v options will change the sort order. If more than one sorting option was given, then the selected processes will be sorted by the last sorting option which was specified. For the processes which have been selected for display, the information to display is selected based on a set of keywords (see the -L, -O, and -o options). The default output format includes, for each process, the process' ID, controlling terminal, CPU time (including both user and sys- tem time), state, and associated command. The process file system (see procfs(5)) should be mounted when ps is exe- cuted, otherwise not all information will be available. The options are as follows: -a Display information about other users' processes as well as your own. This will skip any processes which do not have a control- ling terminal, unless the -x option is also specified. This can be disabled by setting the security.bsd.see_other_uids sysctl to zero. -c Change the ``command'' column output to just contain the exe- cutable name, rather than the full command line. -C Change the way the CPU percentage is calculated by using a ``raw'' CPU calculation that ignores ``resident'' time (this nor- mally has no effect). -e Display the environment as well. -f Show commandline and environment information about swapped out processes. This option is honored only if the UID of the user is 0. -G Display information about processes which are running with the specified real group IDs. -j Print information associated with the following keywords: user, pid, ppid, pgid, sid, jobc, state, tt, time, and command. -L List the set of keywords available for the -O and -o options. -l Display information associated with the following keywords: uid, pid, ppid, cpu, pri, nice, vsz, rss, mwchan, state, tt, time, and command. -M Extract values associated with the name list from the specified core instead of the currently running system. -m Sort by memory usage, instead of the combination of controlling terminal and process ID. -N Extract the name list from the specified system instead of the default, which is the kernel image the system has booted from. -O Add the information associated with the space or comma separated list of keywords specified, after the process ID, in the default information display. Keywords may be appended with an equals (`=') sign and a string. This causes the printed header to use the specified string instead of the standard header. -o Display information associated with the space or comma separated list of keywords specified. Multiple keywords may also be given in the form of more than one -o option. Keywords may be appended with an equals (`=') sign and a string. This causes the printed header to use the specified string instead of the standard header. -p Display information about processes which match the specified process IDs. -r Sort by current CPU usage, instead of the combination of control- ling terminal and process ID. -S Change the way the process time is calculated by summing all exited children to their parent process. -T Display information about processes attached to the device asso- ciated with the standard input. -t Display information about processes attached to the specified terminal devices. -U Display the processes belonging to the specified usernames. -u Display information associated with the following keywords: user, pid, %cpu, %mem, vsz, rss, tt, state, start, time, and command. The -u option implies the -r option. -v Display information associated with the following keywords: pid, state, time, sl, re, pagein, vsz, rss, lim, tsiz, %cpu, %mem, and command. The -v option implies the -m option. -w Use 132 columns to display information, instead of the default cesses which do not have a controlling terminal. This is the opposite of the -X option. If both -X and -x are specified in the same command, then ps will use the one which was specified last. -Z Add mac(4) label to the list of keywords for which ps will dis- play information. A complete list of the available keywords are listed below. Some of these keywords are further specified as follows: %cpu The CPU utilization of the process; this is a decaying average over up to a minute of previous (real) time. Since the time base over which this is computed varies (since processes may be very young) it is possible for the sum of all %cpu fields to exceed 100%. %mem The percentage of real memory used by this process. flags The flags associated with the process as in the include file <sys/proc.h>: P_ADVLOCK 0x00001 Process may hold a POSIX advisory lock P_CONTROLT 0x00002 Has a controlling terminal P_KTHREAD 0x00004 Kernel thread P_NOLOAD 0x00008 Ignore during load avg calculations P_PPWAIT 0x00010 Parent is waiting for child to exec/exit P_PROFIL 0x00020 Has started profiling P_STOPPROF 0x00040 Has thread in requesting to stop prof P_SUGID 0x00100 Had set id privileges since last exec P_SYSTEM 0x00200 System proc: no sigs, stats or swapping P_SINGLE_EXIT 0x00400 Threads suspending should exit, not wait P_TRACED 0x00800 Debugged process being traced P_WAITED 0x01000 Someone is waiting for us P_WEXIT 0x02000 Working on exiting P_EXEC 0x04000 Process called exec P_SA 0x08000 Using scheduler activations P_CONTINUED 0x10000 Proc has continued from a stopped state P_STOPPED_SIG 0x20000 Stopped due to SIGSTOP/SIGTSTP P_STOPPED_TRACE 0x40000 Stopped because of tracing P_STOPPED_SINGLE 0x80000 Only one thread can continue P_PROTECTED 0x100000 Do not kill on memory overcommit P_SIGEVENT 0x200000 Process pending signals changed P_JAILED 0x1000000 Process is in jail P_INEXEC 0x4000000 Process is in execve() label The MAC label of the process. mwchan The event name if the process is blocked normally, or the lock name if the process is blocked on a lock. See the wchan and lockname keywords for details. nice The process scheduling increment (see setpriority(2)). rss the real memory (resident set) size of the process (in 1024 byte units). start The time the command started. If the command started less than 24 hours ago, the start time is displayed using the ``%l:ps.1p'' format described in strftime(3). If the command started less than 7 days ago, the start time is displayed using the ``%a6.15p'' format. Otherwise, the start time is displayed using the ``%e%b%y'' format. state The state is given by a sequence of characters, for example, ``RWNA''. The first character indicates the run state of the process: D Marks a process in disk (or other short term, uninter- ruptible) wait. I Marks a process that is idle (sleeping for longer than about 20 seconds). L Marks a process that is waiting to acquire a lock. R Marks a runnable process. S Marks a process that is sleeping for less than about 20 seconds. T Marks a stopped process. W Marks an idle interrupt thread. Z Marks a dead process (a ``zombie''). Additional characters after these, if any, indicate additional state information: + The process is in the foreground process group of its control terminal. < The process has raised CPU scheduling priority. E The process is trying to exit. J Marks a process which is in jail(2). The hostname of the prison can be found in /proc/<pid>/status. L The process has pages locked in core (for example, for raw I/O). N The process has reduced CPU scheduling priority (see setpriority(2)). s The process is a session leader. V The process is suspended during a vfork(2). W The process is swapped out. X The process is being traced or debugged. tt An abbreviation for the pathname of the controlling terminal, if any. The abbreviation consists of the three letters follow- ing /dev/tty, or, for the console, ``con''. This is followed by a `-' if the process can no longer reach that controlling terminal (i.e., it has been revoked). wchan The event (an address in the system) on which a process waits. be located (usually because it has not been set, as is the case of system processes and/or kernel threads) the command name is printed within square brackets. The ps utility makes an educated guess as to the file name and arguments given when the process was created by examining memory or the swap area. The method is inherently somewhat unreliable and in any event a process is entitled to destroy this information, so the names cannot be depended on too much. The ucomm (accounting) keyword can, how- ever, be depended on.
The following is a complete list of the available keywords and their meanings. Several of them have aliases (keywords which are synonyms). %cpu percentage CPU usage (alias pcpu) %mem percentage memory usage (alias pmem) acflag accounting flag (alias acflg) args command and arguments comm command command command and arguments cpu short-term CPU usage factor (for scheduling) etime elapsed running time flags the process flags, in hexadecimal (alias f) inblk total blocks read (alias inblock) jobc job control count ktrace tracing flags label MAC label lim memoryuse limit logname login name of user who started the process lstart time started majflt total page faults minflt total page reclaims msgrcv total messages received (reads from pipes/sockets) msgsnd total messages sent (writes on pipes/sockets) lockname lock currently blocked on (as a symbolic name) mwchan wait channel or lock currently blocked on nice nice value (alias ni) nivcsw total involuntary context switches nsigs total signals taken (alias nsignals) nswap total swaps in/out nvcsw total voluntary context switches nwchan wait channel (as an address) oublk total blocks written (alias oublock) paddr swap address pagein pageins (same as majflt) pgid process group number pid process ID poip pageouts in progress ppid parent process ID pri scheduling priority re core residency time (in seconds; 127 = infinity) rgid real group ID rgroup group name (from rgid) rlink reverse link on run queue, or 0 rss resident set size rtprio realtime priority (101 = not a realtime process) ruid real user ID ruser user name (from ruid) sid session ID svuid saved UID from a setuid executable tdev control terminal device number time accumulated CPU time, user + system (alias cputime) tpgid control terminal process group ID tsid control terminal session ID tsiz text size (in Kbytes) tt control terminal name (two letter abbreviation) tty full name of control terminal uprocp process pointer ucomm name to be used for accounting uid effective user ID upr scheduling priority on return from system call (alias usrpri) user user name (from UID) vsz virtual size in Kbytes (alias vsize) wchan wait channel (as a symbolic name) xstat exit or stop status (valid only for stopped or zombie process)
The following environment variables affect the execution of ps: COLUMNS If set, specifies the user's preferred output width in column positions. By default, ps attempts to automatically determine the terminal width.
/boot/kernel/kernel default system namelist /proc the mount point of procfs(5)
kill(1), pgrep(1), pkill(1), w(1), kvm(3), strftime(3), mac(4), procfs(5), pstat(8), sysctl(8), mutex(9)
For historical reasons, ps utility under FreeBSD supports a different set of options from what is described by IEEE Std 1003.2 (``POSIX.2''), and what is supported on non-BSD operating systems.
The ps command appeared in Version 4 AT&T UNIX.
Since ps cannot run faster than the system and is run as any other sched- uled process, the information it displays can never be exact. The ps utility does not correctly display argument lists containing multibyte characters. FreeBSD 5.4 March 27, 2004 FreeBSD 5.4
Man(1) output converted with man2html , sed , awk