ps |
[-AaCcdehjlmrSsTuvwx ]
[-k key]
[-M core]
[-N system]
[-O fmt]
[-o fmt]
[-p pid]
[-t tty]
[-U user]
[-W swap] |
ps
displays a header line followed by lines containing
information about running processes. By default, the display includes only
processes that have controlling terminals and are owned by your uid. The
default sort order of controlling terminal and (among processes with the same
controlling terminal) process ID may be changed using the
-k
, -m
, or
-r
options.
The information displayed for each process 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 all processes. This is equivalent to
-a
-x
.
-a
- Display information about other users' processes as well as your own. Note
that this does not display information about processes without controlling
terminals.
-C
- Change the way the CPU percentage is calculated by using a
“raw” CPU calculation that ignores “resident”
time (this normally has no effect).
-c
- Do not display full command with arguments, but only the executable name.
This may be somewhat confusing; for example, all
sh(1) scripts will show as
“sh”.
-d
- Arrange processes into descendancy order and prefix each command with
indentation text showing sibling and parent/child relationships. If either
of the
-m
and -r
options
are also used, they control how sibling processes are sorted relative to
each other.
-e
- Display the environment as well. The environment for other users'
processes can only be displayed by the super-user.
-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.
-k
key
- Sort the output using the space or comma separated list of keywords.
Multiple sort keys may be specified, using any of the
-k
, -m
, or
-r
options. The default sort order is equivalent
to -k
tdev,pid.
-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
core
- Extract values from the specified core file instead of the running
system.
-m
- Sort by memory usage. This is equivalent to
-k
vsz.
-N
system
- Extract the name list from the specified system instead of the default,
“/netbsd”. Ignored unless
-M
is specified.
-O
fmt
- Display information associated with the space or comma separated list of
keywords specified. The
-O
option does not
suppress the default display; it inserts additional keywords just after
the pid keyword in the default display, or after the
pid keyword (if any) in a non-default display
specified before the first use of the -O
flag.
Keywords inserted by multiple -O
options will be
adjacent.
An equals sign (“=”) followed by a customised
header string may be appended to a keyword, as described in more detail
under the -o
option.
-o
fmt
- Display information associated with the space or comma separated list of
keywords specified. Use of the
-o
option
suppresses the set of keywords that would be displayed by default, or
appends to the set of keywords specified by other options.
An equals sign (“=”) followed by a customised
header string may be appended to a keyword. This causes the printed
header to use the specified string instead of the default header
associated with the keyword.
Everything after the first equals sign is part of the
customised header text, and this may include embedded spaces (“
”), commas (“,”), or equals signs
(“=”). To specify multiple keywords with customised
headers, use multiple -o
or
-O
options.
If all the keywords to be displayed have customised headers,
and all the customised headers are entirely empty, then the header line
is not printed at all.
-p
pid
- Display information associated with the specified process ID.
-r
- Sort by current CPU usage. This is equivalent to
-k
%cpu.
-S
- Change the way the process time is calculated by summing all exited
children to their parent process.
-s
- Display one line for each LWP, rather than one line for each process, and
display information associated with the following keywords:
uid, pid,
ppid, cpu,
lid, nlwp,
pri, nice,
vsz, rss,
wchan, lstate,
tt, time, and
command.
-T
- Display information about processes attached to the device associated with
the standard input.
-t
tty
- Display information about processes attached to the specified terminal
device. Use a question mark (“?”) for processes not attached
to a terminal device and a minus sign (“-”) for processes
that have been revoked from their terminal device.
-U
user
- Display processes belonging to the specified user, given either as a user
name or a uid.
-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
swap
- Extract swap information from the specified file instead of the default,
“/dev/drum”. Ignored unless
-M
is specified.
-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 to your window size.
-x
- Also display information about processes without controlling
terminals.
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 (in hexadecimal) 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).
- maxrss
- the maxiumum resident set size of the process (in 1024 byte units).
- 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%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,
“RNs”. The first letter indicates the run state of the
process:
- D
- Marks a process in device or other short term, uninterruptible
wait.
- I
- Marks a process that is idle (sleeping interruptibly for longer than
about
MAXSLP
(default 20) seconds).
- O
- Marks a process running on a processor.
- R
- Marks a runnable process, or one that is in the process of
creation.
- S
- Marks a process that is sleeping interruptibly for less than about
MAXSLP
(default 20) seconds.
- T
- Marks a stopped process.
- U
- Marks a suspended process.
- Z
- Marks a dead process that has exited, but not been waited for (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 LWP is detached (can't be waited for).
- <
- The process has raised CPU scheduling priority.
- a
- The process is using scheduler activations (deprecated).
- E
- The process is in the process of exiting.
- K
- The process is a kernel thread or system process.
- l
- The process has multiple LWPs.
- N
- The process is niced (has reduced CPU scheduling priority) (see
setpriority(2)).
- s
- The process is a session leader.
- V
- The process is suspended during a
vfork(2).
- 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 two letters following
“/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 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
will try to locate the processes'
argument vector from the user area in order to print the command name and
arguments. This method is not reliable because a process is allowed to
destroy this information. The ucomm (accounting)
keyword will always contain the real command name as contained in the
process structure's p_comm field.
If the command vector 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.
To indicate that the argument vector has been tampered with,
ps
will append the real command name to the output
within parentheses if the basename of the first argument in the argument
vector does not match the contents of the real command name.
In addition, ps
checks for the following
two situations and does not append the real command name parenthesized:
- -shellname
- The login process traditionally adds a ‘-’ in front of the
shell name to indicate a login shell.
ps
will not
append parenthesized the command name if it matches with the name in the
first argument of the argument vector, skipping the leading
‘-’.
- daemonname: current-activity
- Daemon processes frequently report their current activity by setting their
name to be like “daemonname: current-activity”.
ps
will not append parenthesized the command name,
if the string preceding the ‘:’ in the first argument of the
argument vector matches the command name.
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)
- comm
- command (the argv[0] value)
- command
- command and arguments (alias args)
- cpu
- short-term CPU usage factor (for scheduling)
- cpuid
- CPU number the current process or lwp is running on.
- ctime
- accumulated CPU time of all children that have exited
- egid
- effective group id
- egroup
- group name (from egid)
- emul
- emulation name
- etime
- elapsed time since the process was started, in the form
[[dd-]hh:]mm:ss
- euid
- effective user id
- euser
- user name (from euid)
- flags
- the process flags, in hexadecimal (alias f)
- gid
- effective group id
- group
- group name (from gid)
- groupnames
- group names (from group access list)
- groups
- group access list
- idrss
- integral unshared data
- isrss
- integral unshared stack
- ixrss
- integral shared memory size
- inblk
- total blocks read (alias inblock)
- jobc
- job control count
- ktrace
- tracing flags
- ktracep
- tracing vnode
- laddr
- kernel virtual address of the struct lwp belonging
to the LWP.
- lid
- ID of the LWP
- lim
- memory use limit
- lname
- descriptive name of the LWP
- logname
- login name of user who started the process (alias
login)
- lstart
- time started
- lstate
- symbolic LWP state
- ltime
- CPU time of the LWP
- majflt
- total page faults
- maxrss
- maximum resident set size
- 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 LWPs in the process
- nsigs
- total signals taken (alias nsignals)
- nvcsw
- total voluntary context switches
- nwchan
- wait channel (as an address)
- oublk
- total blocks written (alias oublock)
- p_ru
- resource usage pointer (valid only for zombie)
- paddr
- kernel virtual address of the struct proc belonging
to the process.
- 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
- rlink
- reverse link on run queue, or 0
- rlwp
- number of LWPs on a processor or run queue
- rss
- resident set size
- rsz
- resident set size + (text size / text use count) (alias
rssize)
- ruid
- real user ID
- ruser
- user name (from ruid)
- sess
- session pointer
- 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)
- stime
- accumulated system CPU time
- svgid
- saved gid from a setgid executable
- svgroup
- group name (from svgid)
- svuid
- saved uid from a setuid executable
- svuser
- user name (from svuid)
- tdev
- control terminal device number
- 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
- uaddr
- kernel virtual address of the struct user belonging
to the LWP.
- 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)
- utime
- accumulated user CPU time
- 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)
- /dev
- special files and device names
- /dev/drum
- default swap device
- /var/run/dev.cdb
- /dev name database
- /var/db/kvm.db
- system name list database
- /netbsd
- default system name list
A ps
utility appeared in
Version 3 AT&T UNIX in section 8 of the
manual.
Since ps
cannot run faster than the system and is run as
any other scheduled process, the information it displays can never be exact.