PS(1) BSD Reference Manual PS(1)NAMEps - process status
SYNOPSISps [-aCehjlmrSTuvwx] [-E user] [-M core] [-N system] [-O fmt] [-o fmt]
[-p pid] [-t tty] [-U user] [-W swap]
ps [-L]
DESCRIPTION
Ps displays a header line followed by lines containing information about
your processes that have controlling terminals. This information is
sorted 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 options are as follows:
-a Display information about other users' processes as well as your
own.
-C Change the way the cpu percentage (%cpu) is calculated by using a
``raw'' cpu calculation that ignores ``resident'' time.
-E Display information about processes with the specified effective
uid. The specified uid may be numeric or symbolic. The -E op-
tion implies the -x option.
-e Display the environment as well.
-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 ``/bsd''.
-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. The
-p option implies the -x option.
-r Sort by current cpu usage, instead of by process ID.
-S Change the way the process time is calculated by summing all ex-
ited 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 information about processes with the specified real uid.
The specified uid may be numeric or symbolic. The -U option im-
plies the -x option.
-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 Extract swap information from the specified file instead of the
default ``/dev/swap''.
-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 re-
gard 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. Normally, the cpu
percentage is scaled by resident time. This scaling produces a
higher percentage for recently-resident programs (such as those
that have been started recently), as they have accumulated their
cpu time over a shorter period. The -C option disables this
scaling. 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 (in hexadecimal) associated with the process as in the
include file <sys/proc.h>:
P_ADVLOCK 0x00001 holds advisory lock
P_ASYNCDAEMON 0x40000 VM paging assistant daemon
P_CONTROLT 0x00002 has control tty
P_EXEC 0x04000 process called exec(2)
P_INMEM 0x00004 u. area locked in core
P_NOCLDSTOP 0x00008 no SIGCHLD when children stop
P_NOSWAP 0x08000 a flag to prevent swap out
P_OWEUPC 0x20000 owe process an addupc() call at
next ast
P_PHYSIO 0x10000 doing physical I/O
P_PPWAIT 0x00010 parent waiting in a vfork(2)
P_PROFIL 0x00020 process being profiled
P_SELECT 0x00040 selecting; wakeup/waiting danger
P_SINTR 0x00080 sleep is interruptible
P_SUGID 0x00100 had privileges since last exec
P_SYSTEM 0x00200 swapper or pager process
P_TIMEOUT 0x00400 timing out during sleep
P_TRACED 0x00800 process is being traced
P_WAITED 0x01000 tracer has seen child stop
P_WEXIT 0x02000 working on exiting
lim The soft limit on memory used, specified via a call to
setrlimit(2). (This is not yet implemented.)
lstart The time the command started, using the format ``%a %b %e
%H:%M:%S %Y'' (i.e. the format used by ctime(3) and asctime(3),
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:%M%p''
format described in strftime(3). If the command started less
than 7 days ago, the start time is displayed using the ``%a%I%p''
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 pro-
cess:
D Marks a process in disk (or other short term, un-inter-
ruptible) wait.
I Marks a process that is idle (sleeping for longer than
about 20 seconds).
R Marks a runnable process.
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.
E The process is trying to exit.
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.
W The process's kernel stack is pageable.
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, ``co'', or for any other de-
vice, the first three letters. 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>''. Ps makes an educated guess as
to the file name and arguments given when the process was created by ex-
amining memory or the swap area. The method is inherently somewhat unre-
liable and in any event a process is entitled to destroy this informa-
tion, so the names cannot be depended on too much. The ucomm (account-
ing) 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); see /sys/sys/acct.h.
command command and arguments
cpu short-term cpu usage factor (for scheduling)
flags the process flags, in hexadecimal (alias f)
inblk total blocks read (alias inblock)
jobc job control count
ktrace tracing flags
ktracep tracing vnode
lim memoryuse limit (currently unimplemented)
logname login name of user who started the process (alias login)
lstart time started
majflt total page faults (currently unimplemented)
minflt total page reclaims (currently unimplemented)
msgrcv total messages received (reads from pipes/sockets)
msgsnd total messages sent (writes on pipes/sockets)
mapent total VM map entries
nice nice value (alias ni)
nivcsw total involuntary context switches
nsigs total signals taken (alias nsignals)
nswap total swaps in/out (currently unimplemented)
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 address of proc structure
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; 999 = infinity)
rgid real group ID
rlink reverse link on run queue, or 0
rss resident set size
rsz resident set size + (text size / text use count) (alias rs-
size)
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; 999 = 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 (major/minor)
time accumulated cpu time, user + system (alias cputime)
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
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)
FILES
/dev special files and device names
/dev/drum default swap device
/dev/kmem default kernel memory
/var/run/dev.db /dev name database
/var/db/kvm_bsd.db system namelist database
/bsd default system namelist
SEE ALSOsystat(1), w(1), kvm(3), strftime(3), pstat(8)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.
If the symbol _KERNBASE is not found in the kernel, ps will attempt to
guess at a likely value; if this value happens to be incorrect, behavior
can be surprising. If this prevents symbolic interpretation of the wchan
field, it will be truncated to the six least-significant hexadecimal dig-
its and printed numerically.
4th Berkeley Distribution April 18, 1994 5
