ps -- process status
ps [-aCcefHhjlmrSTuvwxZ] [-M core] [-N system] [-O fmt] [-o fmt] [-p pid]
[-t tty] [-U username[,username...]]
The ps utility displays a header line followed by lines containing information
about your processes that have controlling terminals. This information
is sorted by controlling terminal, then by process ID.
The information displayed 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 system time), state, and associated command.
The process file system (see procfs(5)) should be mounted when ps is executed,
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 can be disabled by setting the
security.bsd.see_other_uids sysctl to zero.
-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 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
-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, jobc, state, tt, time and command.
-L List the set of available keywords.
-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 default /dev/kmem.
-m Sort by memory usage, instead of by process ID.
-N Extract the name list from the specified system instead of the
-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
-p Display information associated with the specified process ID.
-r Sort by current cpu usage, instead of by 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 associated
with the standard input.
-t Display information about processes attached to the specified
-U Display the processes belonging to the specified username(s).
-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 Display information about processes without controlling terminals.
-Z Add label to the list of keywords for which ps will display
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 advisory
P_CONTROLT 0x00002 Has a controlling terminal
P_INMEM 0x00004 Loaded into memory
P_NOCLDSTOP 0x00008 No SIGCHLD when children stop
P_PPWAIT 0x00010 Parent is waiting for child to
P_PROFIL 0x00020 Has started profiling
P_SELECT 0x00040 Selecting; wakeup/waiting danger
P_SINTR 0x00080 Sleep is interruptible
P_SUGID 0x00100 Had set id privileges since last
P_SYSTEM 0x00200 System proc: no sigs, stats or
P_TIMEOUT 0x00400 Timing out during sleep
P_TRACED 0x00800 Debugged process being traced
P_WAITED 0x01000 Debugging process has waited for
P_WEXIT 0x02000 Working on exiting
P_EXEC 0x04000 Process called exec
P_OWEUPC 0x20000 Owe process an addupc() call at
P_SWAPPING 0x40000 Process is being swapped
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.
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, uninterruptible)
I Marks a process that is idle (sleeping for longer than
about 20 seconds).
J Marks a process which is in jail(2). The hostname of
the prison can be found in `/proc/<pid>/status'.
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.
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.
> The process has specified a soft limit on memory
requirements and is currently exceeding that limit;
such a process is (necessarily) not swapped.
A the process has asked for random page replacement
(MADV_RANDOM, from madvise(2), for example, lisp in a
E The process is trying to exit.
L The process has pages locked in core (for example, for
N The process has reduced CPU scheduling priority (see
S The process has asked for FIFO page replacement
(MADV_SEQUENTIAL, from madvise(2), for example, a large
image processing program using virtual memory to
sequentially address voluminous data).
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 following
/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.
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>''. 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, however, 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
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
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
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.
/dev/kmem default kernel memory
/dev/lomac interface used to query the lomac(4) KLD
/var/run/dev.db /dev name database
/var/db/kvm_kernel.db system namelist database
/boot/kernel/kernel default system namelist
/proc the mount point of procfs(5)
kill(1), w(1), kvm(3), strftime(3), lomac(4), procfs(5), pstat(8),
The ps command appeared in Version 4 AT&T UNIX.
Since ps cannot run faster than the system and is run as any other scheduled
process, the information it displays can never be exact.
FreeBSD 5.2.1 April 18, 1994 FreeBSD 5.2.1 [ Back ]