PS(1) BSD General Commands Manual PS(1)NAMEps — process status
SYNOPSISps [-aCcefHhjlmrRSTuvwx] [-M core] [-N system] [-O fmt] [-o fmt] [-p pid]
[-t tty] [-U username]
ps [-L]
DESCRIPTION
The ps utility displays a header line followed by lines containing infor‐
mation about your processes that have controlling terminals. This infor‐
mation 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 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 can be disabled by setting the
security.ps_showallprocs 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.
-H Print one line per lightweight process (LWP) instead of one line
per process. When this option is set and the -o option is not
set, the tid column is inserted in the output format after the
pid one.
-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, sess, 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, wchan, state, tt, time, and
command.
-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
default /boot/kernel.
-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. 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 associated with the specified process ID.
-r Sort by current CPU usage, instead of by process ID.
-R Subsort by parent/child chain. This very useful option makes the
parent/child associations clear and understandable.
-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 device.
-U Display the processes belonging to the specified username.
-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 termi‐
nals.
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>.
lim The soft limit on memory used, specified via a call to
setrlimit(2).
lstart The exact time the command started, using the ``%c'' format
described in strftime(3).
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 letters, for example, “RWNA”.
The first letter indicates the run state of the process:
B Marks a blocked kernel thread.
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).
J Marks a process which is in jail(2). The hostname of the
prison can be found in /proc/⟨pid⟩/status.
R Marks a runnable process and is followed by the CPU num‐
ber.
S Marks a process that is sleeping for less than about 20
seconds.
T Marks a stopped process.
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.
> The process has specified a soft limit on memory require‐
ments 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(1) in a
garbage collect).
E The process is trying to exit.
L The process has pages locked in core (for example, for
raw I/O).
M On SMP systems indicates a process or thread which is not
holding the MP lock (the Big Giant Lock).
N The process has reduced CPU scheduling priority (see
setpriority(2)).
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 sequen‐
tially 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 termi‐
nal (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. Note that blocked threads often
only have ascii wchan's.
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 edu‐
cated 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.
KEYWORDS
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)
batch batchness of the process (higher numbers mean less interactiv‐
ity)
command command and arguments
cpu short-term CPU usage factor (for scheduling)
f the process flags, in hexadecimal (alias flags)
inblk total blocks read (alias inblock)
jail jail ID
jobc job control count
ktrace tracing flags
lastcpu CPU ID the process was last scheduled on
lim memoryuse limit
login login name of user who started the process (alias logname)
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
nlwp number of lightweight processes
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 (lower == better)
re core residency time (in seconds; 127 = infinity)
rgid real group ID
rss resident set size
rsz resident set size + (text size / text use count) (alias
rssize)
rtprio realtime priority (101 = not a realtime process)
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)
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
tdpri LWKT thread priority (0-31, 31 highest), and critical section
count
tid thread ID (aka lightweight process ID)
time accumulated CPU time, user + system (alias cputime)
tpgid control terminal process group ID
tsess control terminal session pointer
tsig pending thread signals
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
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)
FILES
/dev/kmem default kernel memory
/var/run/dev.db /dev name database
/var/db/kvm_kernel.db system namelist database
/boot/kernel default system namelist
/proc the mount point of procfs(5)SEE ALSOkill(1), w(1), kvm(3), strftime(3), procfs(5), pstat(8), sysctl(8)HISTORY
The ps command appeared in Version 4 AT&T UNIX.
BUGS
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.
BSD September 2, 2008 BSD
