PS(1) BSD General Commands Manual PS(1)NAMEps — process status
SYNOPSISps [-aCcdefHhjlmrSTuvwXxZ] [-O fmt | -o fmt] [-G gid[,gid...]] [-M core]
[-N system] [-p pid[,pid...]] [-t tty[,tty...]] [-U user[,user...]]
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
-c Change the “command” column output to just contain the executable
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 normally has
-d Arrange processes into descendancy order and prefix each command
with indentation text showing sibling and parent/child relation‐
ships. If either of the -m and -r options are also used, they
control how sibling processes are sorted relative to eachother.
-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
-G Display information about processes which are running with the
specified real group IDs.
-H Show all of the kernel visible threads associated with each
process. Depending on the threading package that is in use, this
may show only the process, only the kernel scheduled entities, or
all of the process threads.
-h Repeat the information header as often as necessary to guarantee
one header per page of information.
-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
-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. The last keyword in the list may be
appended with an equals (‘=’) sign and a string that spans the
rest of the argument, and can contain space and comma characters.
This causes the printed header to use the specified string
instead of the standard header. Multiple keywords may also be
given in the form of more than one -o option. So the header
texts for multiple keywords can be changed. If all keywords have
empty header texts, no header line is written.
-p Display information about processes which match the specified
-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
-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
which is your window size. If the -w option is specified more
than once, ps will use as many columns as necessary without
regard for your window size.
-X When displaying processes matched by other options, skip any pro‐
cesses which do not have a controlling terminal.
-x When displaying processes matched by other options, include pro‐
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
-Z Add mac(4) label to the list of keywords for which ps will dis‐
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
%mem The percentage of real memory used by this process.
flags The flags associated with the process as in the include file
P_ADVLOCK 0x00001 Process may hold a POSIX
P_CONTROLT 0x00002 Has a controlling terminal
P_KTHREAD 0x00004 Kernel thread
P_PPWAIT 0x00010 Parent is waiting for child
P_PROFIL 0x00020 Has started profiling
P_STOPPROF 0x00040 Has thread in requesting to
P_HASTHREADS 0x00080 Has had threads (no cleanup
P_SUGID 0x00100 Had set id privileges since
P_SYSTEM 0x00200 System proc: no sigs, stats
P_SINGLE_EXIT 0x00400 Threads suspending should
exit, not wait
P_TRACED 0x00800 Debugged process being
P_WAITED 0x01000 Someone is waiting for us
P_WEXIT 0x02000 Working on exiting
P_EXEC 0x04000 Process called exec
P_WKILLED 0x08000 Killed, shall go to
kernel/user boundary ASAP
P_CONTINUED 0x10000 Proc has continued from a
P_STOPPED_SIG 0x20000 Stopped due to
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
P_SIGEVENT 0x200000 Process pending signals
P_SINGLE_BOUNDARY 0x400000 Threads should suspend at
P_HWPMC 0x800000 Process is using HWPMCs
P_JAILED 0x1000000 Process is in jail
P_INEXEC 0x4000000 Process is in execve()
P_STATCHILD 0x8000000 Child process stopped or
P_INMEM 0x10000000 Loaded into memory
P_SWAPPINGOUT 0x20000000 Process is being swapped out
P_SWAPPINGIN 0x40000000 Process is being swapped in
label The MAC label of the process.
lim The soft limit on memory used, specified via a call to
lstart The exact time the command started, using the ‘%c’ format
described in strftime(3).
lockname The name of the lock that the process is currently blocked on.
If the name is invalid or unknown, then “???” is displayed.
logname The login name associated with the session the process is in
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
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
D Marks a process in disk (or other short term, uninter‐
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
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
+ The process is in the foreground process group of its
< 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
N The process has reduced CPU scheduling priority (see
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 ter‐
minal (i.e., it has been revoked).
wchan The event (an address in the system) on which a process waits.
When printed numerically, the initial part of the address is
trimmed off and the result is printed in hex, for example,
0x80324000 prints as 324000.
When printing using the command keyword, a process that has exited and
has a parent that has not yet waited for the process (in other words, a
zombie) is listed as “<defunct>”, and a process which is blocked while
trying to exit is listed as “<exiting>”. If the arguments cannot 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 first tries to obtain the arguments
cached by the kernel (if they were shorter than the value of the
kern.ps_arg_cache_limit sysctl). The process can change the arguments
shown with setproctitle(3). Otherwise, ps makes an educated guess as to
the file name and arguments given when the process was created by examin‐
ing memory or the swap area. The method is inherently somewhat unreli‐
able and in any event a process is entitled to destroy this information.
The ucomm (accounting) keyword can, however, be depended on. If the
arguments are unavailable or do not agree with the ucomm keyword, the
value for the ucomm keyword is appended to the arguments in parentheses.
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
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)
jid jail ID
jobc job control count
ktrace tracing flags
label MAC label
lim memoryuse limit
lockname lock currently blocked on (as a symbolic name)
logname login name of user who started the session
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)
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
sig pending signals (alias pending)
sigcatch caught signals (alias caught)
sigignore ignored signals (alias ignored)
sigmask blocked signals (alias blocked)
sl sleep time (in seconds; 127 = infinity)
start time started
state symbolic process state (alias stat)
svgid saved gid from a setgid executable
svuid saved UID from a setuid executable
tdaddr thread address
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)
Note that the pending column displays bitmask of signals pending in the
process queue when -H option is not specified, otherwise the per-thread
queue of pending signals is shown.
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)SEE ALSOkill(1), pgrep(1), pkill(1), procstat(1), w(1), kvm(3), strftime(3),
mac(4), procfs(5), pstat(8), sysctl(8), mutex(9)STANDARDS
For historical reasons, the 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
BSD July 24, 2010 BSD