ps - process status
ps [-][aCcehjklmrSTuvwx] [-M core] [-N system] [-O fmt] [-o
fmt] [-p pid]
[-t tty] [-U username] [-W swap]
The ps utility displays information about active processes.
no options, ps prints information about processes associated
The information displayed is selected based on a set of keywords (and for
even more control, see the -L, -O, and -o options). The default output
format includes, for each process, the process's ID, controlling terminal,
CPU time (including both user and system time), state,
The options are as follows:
-a Display information about other users' processes as
well as your
-C Change the way the CPU percentage is calculated by
``raw'' CPU calculation that ignores ``resident''
time (this normally
has no effect).
-c Do not display full command with arguments, but only
name. This may be somewhat confusing; for
sh(1) scripts will show as ``sh''.
-e Display the environment as well.
-h Repeat the information header as often as necessary
one header per page of information.
-j Print information associated with the following keywords: user,
pid, ppid, pgid, sess, jobc, state, tt, time, and
-k Also display information about kernel threads.
-L List the set of available keywords.
-l Display information associated with the following
pid, ppid, cpu, pri, nice, vsz, rss, wchan, state,
tt, time and
Extract values associated with the name list from
core instead of the running kernel.
-m Sort by memory usage, instead of by start time ID.
Extract the name list from the specified system instead of the
-O fmt Add the information associated with the space or
list of keywords specified, after the process ID, in
information display. Keywords may be appended with
sign (`=') and a string. This causes the printed
header to use
the specified string instead of the standard header.
-o fmt Display information associated with the space or
list of keywords specified. Keywords may be appended with an
equals sign (`=') and a string. This causes the
to use the specified string instead of the standard
-p pid Display information associated with the specified
-r Sort by current CPU usage, instead of by start time
-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
with the standard input.
-t tty Display information about processes attached to the
Display the processes belonging to the specified
-u Display information associated with the following
pid, %cpu, %mem, vsz, rss, tt, state, start, time,
The -u option implies the -r option.
-v Display information associated with the following
state, time, sl, re, pagein, vsz, rss, lim, tsiz,
%cpu, %mem and
command. The -v option implies the -m option.
Extract swap information from the specified file instead of the
-w Use 132 columns to display information, instead of
which is your window size. If the -w option is
than once, ps will use as many columns as necessary
for your window size.
-x Display information about processes without controlling terminals.
All 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
%mem The percentage of real memory used by this process.
flags The flags (in hexadecimal) associated with the process as in the
include file <sys/proc.h>:
P_ADVLOCK 0x0000001 process may hold a
P_CONTROLT 0x0000002 process has a controlling terminal
P_INMEM 0x0000004 process is loaded into
P_NOCLDSTOP 0x0000008 no SIGCHLD when children stop
P_PPWAIT 0x0000010 parent is waiting for
P_PROFIL 0x0000020 process has started
P_SELECT 0x0000040 selecting; wakeup/waiting danger
P_SINTR 0x0000080 sleep is interruptible
P_SUGID 0x0000100 process had set id
P_SYSTEM 0x0000200 system process: no
sigs, stats or
P_TIMEOUT 0x0000400 timing out during
P_TRACED 0x0000800 process is being
P_WAITED 0x0001000 debugging process has
P_WEXIT 0x0002000 working on exiting
P_EXEC 0x0004000 process called exec(3)
P_OWEUPC 0x0008000 owe process an
addupc() call at
P_FSTRACE 0x0010000 tracing via file system
P_SSTEP 0x0020000 process needs singlestep fixup
P_SUGIDEXEC 0x0040000 last exec(3) was
P_NOCLDWAIT 0x0080000 let pid 1 wait for my
P_NOZOMBIE 0x0100000 pid 1 waits for me instead of dad
P_INEXEC 0x0200000 process is doing an
exec right now
P_SYSTRACE 0x0400000 process system call
lim The soft limit on memory used, specified via a call
lstart The exact time the command started, using the ``%c''
nice The process scheduling increment (see setpriority(2)).
rss The real memory (resident set) size of the process
(in 1024 byte
start The time the command started. If the command started less than
24 hours ago, the start time is displayed using the
format described in strftime(3). If the command
than 7 days ago, the start time is displayed using
format. Otherwise, the start time is displayed using the
state The state is given by a sequence of letters, for example,
``RWNA''. The first letter indicates the run state
of the process:
D Marks a process in disk (or other short
I Marks a process that is idle (sleeping for
about 20 seconds).
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
+ 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
and is currently exceeding that limit;
such a process
is (necessarily) not swapped.
E The process is trying to exit.
K The process is a kernel thread.
L The process has pages locked in core (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.
x The process is being monitored by systrace(1).
tt An abbreviation for the pathname of the controlling
any. The abbreviation consists of the two letters
``/dev/tty'', or, for the console, ``co''. 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
trimmed off and the result is printed in hex; for
0x80324000 prints as 324000.
When printing using the command keyword, a process that has
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
trying to exit is listed as ``<exiting>''. ps 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
and in any event a process is entitled to destroy
so the names cannot be depended on too much. The
keyword can, however, be depended on.
The following is a complete list of the available keywords
meanings. Several of them have aliases (keywords which are
%cpu percentage CPU usage (alias pcpu)
%mem percentage memory usage (alias pmem)
acflag accounting flag (alias acflg)
command command and arguments (alias args)
cpu short-term CPU usage factor (for scheduling)
cpuid CPU ID (zero on single processor systems)
dsiz data size (in Kbytes)
emul name of system call emulation environment
flags the process flags, in hexadecimal (alias f)
gid effective group
group text name of effective group ID
holdcnt number of holds on the process (if non-zero, process can't be
inblk total blocks read (alias inblock)
jobc job control count
ktrace tracing flags
ktracep tracing vnode
lim memory usage limit
logname login name of user who started the process (alias
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)
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)
p_ru resource usage (valid only for zombie)
paddr swap address
pagein pageins (same as majflt)
pgid process group number
pid process ID
ppid parent process ID
pri scheduling priority
re core residency time (in seconds; 127 = infinity)
rgid real group ID
rgroup text name of real group ID
rlink reverse link on run queue, or 0
rss resident set size
rsz resident set size + (text size / text use count)
ruid real user ID
ruser user name (from ruid)
sess session pointer
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)
ssiz stack size (in Kbytes)
start time started (alias etime)
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
tpgid control terminal process group ID
tsess control terminal session pointer
tsiz text size (in Kbytes)
tt control terminal name (two letter abbreviation)
tty full name of control terminal
ucomm name to be used for accounting (alias comm)
uid effective user ID
upr scheduling priority on return from system call
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
/dev special files and device names
/dev/drum default swap device
/var/run/dev.db /dev name database
/var/db/kvm_bsd.db system namelist database
$ ps -auxw
Display information on all system processes.
fstat(1), kill(1), pgrep(1), pkill(1), procmap(1), sh(1),
kvm(3), strftime(3), dev_mkdb(8), pstat(8)
A ps command appeared in Version 3 AT&T UNIX in section 8 of
Since ps cannot run faster than the system and is run as any
process, the information it displays can never be exact.
OpenBSD 3.6 April 18, 1994
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