Provided by: procps_3.3.10-4ubuntu2_amd64
NAME
ps - report a snapshot of the current processes.
SYNOPSIS
ps [options]
DESCRIPTION
ps displays information about a selection of the active processes. If you want a
repetitive update of the selection and the displayed information, use top(1) instead.
This version of
ps accepts several kinds of options:
1 UNIX options, which may be grouped and must be preceded by a dash.
2 BSD options, which may be grouped and must not be used with a dash.
3 GNU long options, which are preceded by two dashes.
Options of different types may be freely mixed, but conflicts can appear. There are some
synonymous options, which are functionally identical, due to the many standards and
ps
implementations that this
ps is compatible with.
Note that "
ps -aux" is distinct from "
ps aux". The POSIX and UNIX standards require that
"
ps -aux" print all processes owned by a user named "x", as well as printing all processes
that would be selected by the
-a option. If the user named "x" does not exist, this
ps
may interpret the command as "
ps aux" instead and print a warning. This behavior is
intended to aid in transitioning old scripts and habits. It is fragile, subject to
change, and thus should not be relied upon.
By default,
ps selects all processes with the same effective user ID (euid=EUID) as the
current user and associated with the same terminal as the invoker. It displays the
process ID (pid=PID), the terminal associated with the process (tname=TTY), the cumulated
CPU time in [DD-]hh:mm:ss format (time=TIME), and the executable name (ucmd=CMD). Output
is unsorted by default.
The use of BSD-style options will add process state (stat=STAT) to the default display and
show the command args (args=COMMAND) instead of the executable name. You can override
this with the
PS_FORMAT environment variable. The use of BSD-style options will also
change the process selection to include processes on other terminals (TTYs) that are owned
by you; alternately, this may be described as setting the selection to be the set of all
processes filtered to exclude processes owned by other users or not on a terminal. These
effects are not considered when options are described as being "identical" below, so
-M
will be considered identical to
Z and so on.
Except as described below, process selection options are additive. The default selection
is discarded, and then the selected processes are added to the set of processes to be
displayed. A process will thus be shown if it meets any of the given selection criteria.
EXAMPLES
To see every process on the system using standard syntax:
ps -e
ps -ef
ps -eF
ps -ely
To see every process on the system using BSD syntax:
ps ax
ps axu
To print a process tree:
ps -ejH
ps axjf
To get info about threads:
ps -eLf
ps axms
To get security info:
ps -eo euser,ruser,suser,fuser,f,comm,label
ps axZ
ps -eM
To see every process running as root (real & effective ID) in user format:
ps -U root -u root u
To see every process with a user-defined format:
ps -eo pid,tid,class,rtprio,ni,pri,psr,pcpu,stat,wchan:14,comm
ps axo stat,euid,ruid,tty,tpgid,sess,pgrp,ppid,pid,pcpu,comm
ps -Ao pid,tt,user,fname,tmout,f,wchan
Print only the process IDs of syslogd:
ps -C syslogd -o pid=
Print only the name of PID 42:
ps -q 42 -o comm=
SIMPLE PROCESS SELECTION
a Lift the BSD-style "only yourself" restriction, which is imposed upon the set of
all processes when some BSD-style (without "-") options are used or when the
ps
personality setting is BSD-like. The set of processes selected in this manner is
in addition to the set of processes selected by other means. An alternate
description is that this option causes
ps to list all processes with a terminal
(tty), or to list all processes when used together with the
x option.
-A Select all processes. Identical to
-e.
-a Select all processes except both session leaders (see getsid(2)) and processes not
associated with a terminal.
-d Select all processes except session leaders.
--deselect
Select all processes except those that fulfill the specified conditions (negates
the selection). Identical to
-N.
-e Select all processes. Identical to
-A.
g Really all, even session leaders. This flag is obsolete and may be discontinued in
a future release. It is normally implied by the
a flag, and is only useful when
operating in the sunos4 personality.
-N Select all processes except those that fulfill the specified conditions (negates
the selection). Identical to
--deselect.
T Select all processes associated with this terminal. Identical to the
t option
without any argument.
r Restrict the selection to only running processes.
x Lift the BSD-style "must have a tty" restriction, which is imposed upon the set of
all processes when some BSD-style (without "-") options are used or when the
ps
personality setting is BSD-like. The set of processes selected in this manner is
in addition to the set of processes selected by other means. An alternate
description is that this option causes
ps to list all processes owned by you (same
EUID as
ps), or to list all processes when used together with the
a option.
PROCESS SELECTION BY LIST
These options accept a single argument in the form of a blank-separated or comma-separated
list. They can be used multiple times. For example:
ps -p "1 2" -p 3,4
-123 Identical to
--pid 123.
123 Identical to
--pid 123.
-C cmdlist
Select by command name. This selects the processes whose executable name is given
in cmdlist.
-G grplist
Select by real group ID (RGID) or name. This selects the processes whose real
group name or ID is in the grplist list. The real group ID identifies the group of
the user who created the process, see getgid(2).
-g grplist
Select by session OR by effective group name. Selection by session is specified by
many standards, but selection by effective group is the logical behavior that
several other operating systems use. This
ps will select by session when the list
is completely numeric (as sessions are). Group ID numbers will work only when some
group names are also specified. See the
-s and
--group options.
--Group grplist
Select by real group ID (RGID) or name. Identical to
-G.
--group grplist
Select by effective group ID (EGID) or name. This selects the processes whose
effective group name or ID is in grplist. The effective group ID describes the
group whose file access permissions are used by the process (see getegid(2)). The
-g option is often an alternative to
--group.
p pidlist
Select by process ID. Identical to
-p and
--pid.
-p pidlist
Select by PID. This selects the processes whose process ID numbers appear in
pidlist. Identical to
p and
--pid.
--pid pidlist
Select by process ID. Identical to
-p and
p.
--ppid pidlist
Select by parent process ID. This selects the processes with a parent process ID
in pidlist. That is, it selects processes that are children of those listed in
pidlist.
q pidlist
Select by process ID (quick mode). Identical to
-q and
--quick-pid.
-q pidlist
Select by PID (quick mode). This selects the processes whose process ID numbers
appear in pidlist. With this option
ps reads the necessary info only for the pids
listed in the pidlist and doesn't apply additional filtering rules. The order of
pids is unsorted and preserved. No additional selection options, sorting and forest
type listings are allowed in this mode. Identical to
q and
--quick-pid.
--quick-pid pidlist
Select by process ID (quick mode). Identical to
-q and
q.
-s sesslist
Select by session ID. This selects the processes with a session ID specified in
sesslist.
--sid sesslist
Select by session ID. Identical to
-s.
t ttylist
Select by tty. Nearly identical to
-t and
--tty, but can also be used with an
empty ttylist to indicate the terminal associated with
ps. Using the
T option is
considered cleaner than using
t with an empty ttylist.
-t ttylist
Select by tty. This selects the processes associated with the terminals given in
ttylist. Terminals (ttys, or screens for text output) can be specified in several
forms: /dev/ttyS1, ttyS1, S1. A plain "-" may be used to select processes not
attached to any terminal.
--tty ttylist
Select by terminal. Identical to
-t and
t.
U userlist
Select by effective user ID (EUID) or name. This selects the processes whose
effective user name or ID is in userlist. The effective user ID describes the user
whose file access permissions are used by the process (see geteuid(2)). Identical
to
-u and
--user.
-U userlist
Select by real user ID (RUID) or name. It selects the processes whose real user
name or ID is in the userlist list. The real user ID identifies the user who
created the process, see getuid(2).
-u userlist
Select by effective user ID (EUID) or name. This selects the processes whose
effective user name or ID is in userlist.
The effective user ID describes the user whose file access permissions are used by
the process (see geteuid(2)). Identical to
U and
--user.
--User userlist
Select by real user ID (RUID) or name. Identical to
-U.
--user userlist
Select by effective user ID (EUID) or name. Identical to
-u and
U.
OUTPUT FORMAT CONTROL
These options are used to choose the information displayed by
ps. The output may differ
by personality.
-c Show different scheduler information for the
-l option.
--context
Display security context format (for SELinux).
-f Do full-format listing. This option can be combined with many other UNIX-style
options to add additional columns. It also causes the command arguments to be
printed. When used with
-L, the NLWP (number of threads) and LWP (thread ID)
columns will be added. See the
c option, the format keyword
args, and the format
keyword
comm.
-F Extra full format. See the
-f option, which
-F implies.
--format format
user-defined format. Identical to
-o and
o.
j BSD job control format.
-j Jobs format.
l Display BSD long format.
-l Long format. The
-y option is often useful with this.
-M Add a column of security data. Identical to
Z (for SELinux).
O format
is preloaded
o (overloaded). The BSD
O option can act like
-O (user-defined output
format with some common fields predefined) or can be used to specify sort order.
Heuristics are used to determine the behavior of this option. To ensure that the
desired behavior is obtained (sorting or formatting), specify the option in some
other way (e.g. with
-O or
--sort). When used as a formatting option, it is
identical to
-O, with the BSD personality.
-O format
Like
-o, but preloaded with some default columns. Identical to
-o pid,format
,
state,tname,time,command or
-o pid,format
,tname,time,cmd, see
-o below.
o format
Specify user-defined format. Identical to
-o and
--format.
-o format
User-defined format. format is a single argument in the form of a blank-separated
or comma-separated list, which offers a way to specify individual output columns.
The recognized keywords are described in the
STANDARD FORMAT SPECIFIERS section
below. Headers may be renamed (
ps -o pid,ruser=RealUser -o comm=Command) as
desired. If all column headers are empty (
ps -o pid= -o comm=) then the header
line will not be output. Column width will increase as needed for wide headers;
this may be used to widen up columns such as WCHAN (
ps -o pid,wchan=WIDE-WCHAN-
COLUMN -o comm). Explicit width control (
ps opid,wchan:42,cmd) is offered too.
The behavior of
ps -o pid=X,comm=Y varies with personality; output may be one
column named "X,comm=Y" or two columns named "X" and "Y". Use multiple
-o options
when in doubt. Use the
PS_FORMAT environment variable to specify a default as
desired; DefSysV and DefBSD are macros that may be used to choose the default UNIX
or BSD columns.
s Display signal format.
u Display user-oriented format.
v Display virtual memory format.
X Register format.
-y Do not show flags; show rss in place of addr. This option can only be used with
-l.
Z Add a column of security data. Identical to
-M (for SELinux).
OUTPUT MODIFIERS
c Show the true command name. This is derived from the name of the executable file,
rather than from the argv value. Command arguments and any modifications to them
are thus not shown. This option effectively turns the
args format keyword into the
comm format keyword; it is useful with the
-f format option and with the various
BSD-style format options, which all normally display the command arguments. See
the
-f option, the format keyword
args, and the format keyword
comm.
--cols n
Set screen width.
--columns n
Set screen width.
--cumulative
Include some dead child process data (as a sum with the parent).
e Show the environment after the command.
f ASCII art process hierarchy (forest).
--forest
ASCII art process tree.
h No header. (or, one header per screen in the BSD personality). The
h option is
problematic. Standard BSD
ps uses this option to print a header on each page of
output, but older Linux
ps uses this option to totally disable the header. This
version of
ps follows the Linux usage of not printing the header unless the BSD
personality has been selected, in which case it prints a header on each page of
output. Regardless of the current personality, you can use the long options
--headers and
--no-headers to enable printing headers each page or disable headers
entirely, respectively.
-H Show process hierarchy (forest).
--headers
Repeat header lines, one per page of output.
k spec Specify sorting order. Sorting syntax is [
+|
-]key[,[
+|
-]key[,...]]. Choose a
multi-letter key from the
STANDARD FORMAT SPECIFIERS section. The "+" is optional
since default direction is increasing numerical or lexicographic order. Identical
to
--sort.
Examples:
ps jaxkuid,-ppid,+pid
ps axk comm o comm,args
ps kstart_time -ef
--lines n
Set screen height.
-n namelist
Set namelist file. Identical to
N. The namelist file is needed for a proper WCHAN
display, and must match the current Linux kernel exactly for correct output.
Without this option, the default search path for the namelist is:
$PS_SYSMAP
$PS_SYSTEM_MAP
/proc/*/wchan
/boot/System.map-$(uname -r)
/boot/System.map
/lib/modules/$(uname -r)/System.map
/usr/src/linux/System.map
/System.map
n Numeric output for WCHAN and USER (including all types of UID and GID).
N namelist
Specify namelist file. Identical to
-n, see
-n above.
--no-headers
Print no header line at all.
--no-heading is an alias for this option.
O order
Sorting order (overloaded). The BSD
O option can act like
-O (user-defined output
format with some common fields predefined) or can be used to specify sort order.
Heuristics are used to determine the behavior of this option. To ensure that the
desired behavior is obtained (sorting or formatting), specify the option in some
other way (e.g. with
-O or
--sort).
For sorting, obsolete BSD
O option syntax is
O[
+|
-]k1[,[
+|
-]k2[,...]]. It orders
the processes listing according to the multilevel sort specified by the sequence of
one-letter short keys k1,k2, ... described in the
OBSOLETE SORT KEYS section
below. The "+" is currently optional, merely re-iterating the default direction on
a key, but may help to distinguish an
O sort from an
O format. The "-" reverses
direction only on the key it precedes.
--rows n
Set screen height.
S Sum up some information, such as CPU usage, from dead child processes into their
parent. This is useful for examining a system where a parent process repeatedly
forks off short-lived children to do work.
--sort spec
Specify sorting order. Sorting syntax is [
+|
-]key[,[
+|
-]key[,...]]. Choose a
multi-letter key from the
STANDARD FORMAT SPECIFIERS section. The "+" is optional
since default direction is increasing numerical or lexicographic order. Identical
to
k. For example:
ps jax --sort=uid,-ppid,+pid
w Wide output. Use this option twice for unlimited width.
-w Wide output. Use this option twice for unlimited width.
--width n
Set screen width.
THREAD DISPLAY
H Show threads as if they were processes.
-L Show threads, possibly with LWP and NLWP columns.
m Show threads after processes.
-m Show threads after processes.
-T Show threads, possibly with SPID column.
OTHER INFORMATION
--help section
Print a help message. The section argument can be one of simple, list, output,
threads, misc or all. The argument can be shortened to one of the underlined
letters as in: s|l|o|t|m|a.
--info Print debugging info.
L List all format specifiers.
V Print the procps-ng version.
-V Print the procps-ng version.
--version
Print the procps-ng version.
NOTES
This
ps works by reading the virtual files in /proc. This
ps does not need to be setuid
kmem or have any privileges to run. Do not give this
ps any special permissions.
This
ps needs access to namelist data for proper WCHAN display. For kernels prior to 2.6,
the System.map file must be installed.
CPU usage is currently expressed as the percentage of time spent running during the entire
lifetime of a process. This is not ideal, and it does not conform to the standards that
ps otherwise conforms to. CPU usage is unlikely to add up to exactly 100%.
The SIZE and RSS fields don't count some parts of a process including the page tables,
kernel stack, struct thread_info, and struct task_struct. This is usually at least 20 KiB
of memory that is always resident. SIZE is the virtual size of the process (code+data+
stack).
Processes marked <defunct> are dead processes (so-called "zombies") that remain because
their parent has not destroyed them properly. These processes will be destroyed by
init(8) if the parent process exits.
If the length of the username is greater than the length of the display column, the
numeric user ID is displayed instead.
Commands options such as
ps -aux are not recommended as it is a confusion of two different
standards. According to the POSIX and UNIX standards, the above command asks to display
all processes with a TTY (generally the commands users are running) plus all processes
owned by a user named "x". If that user doesn't exist, then
ps will assume you really
meant "
ps aux".
PROCESS FLAGS
The sum of these values is displayed in the "F" column, which is provided by the
flags
output specifier:
1 forked but didn't exec
4 used super-user privileges
PROCESS STATE CODES
Here are the different values that the
s,
stat and
state output specifiers (header "STAT"
or "S") will display to describe the state of a process:
D uninterruptible sleep (usually IO)
R running or runnable (on run queue)
S interruptible sleep (waiting for an event to complete)
T stopped by job control signal
t stopped by debugger during the tracing
W paging (not valid since the 2.6.xx kernel)
X dead (should never be seen)
Z defunct ("zombie") process, terminated but not reaped by its parent
For BSD formats and when the
stat keyword is used, additional characters may be displayed:
< high-priority (not nice to other users)
N low-priority (nice to other users)
L has pages locked into memory (for real-time and custom IO)
s is a session leader
l is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)
+ is in the foreground process group
OBSOLETE SORT KEYS
These keys are used by the BSD
O option (when it is used for sorting). The GNU
--sort
option doesn't use these keys, but the specifiers described below in the
STANDARD FORMAT
SPECIFIERS section. Note that the values used in sorting are the internal values
ps uses
and not the "cooked" values used in some of the output format fields (e.g. sorting on tty
will sort into device number, not according to the terminal name displayed). Pipe
ps
output into the
sort(1) command if you want to sort the cooked values.
KEY LONG DESCRIPTION
c cmd simple name of executable
C pcpu cpu utilization
f flags flags as in long format F field
g pgrp process group ID
G tpgid controlling tty process group ID
j cutime cumulative user time
J cstime cumulative system time
k utime user time
m min_flt number of minor page faults
M maj_flt number of major page faults
n cmin_flt cumulative minor page faults
N cmaj_flt cumulative major page faults
o session session ID
p pid process ID
P ppid parent process ID
r rss resident set size
R resident resident pages
s size memory size in kilobytes
S share amount of shared pages
t tty the device number of the controlling tty
T start_time time process was started
U uid user ID number
u user user name
v vsize total VM size in KiB
y priority kernel scheduling priority
AIX FORMAT DESCRIPTORS
This
ps supports AIX format descriptors, which work somewhat like the formatting codes of
printf(1) and printf(3). For example, the normal default output can be produced with
this:
ps -eo "%p %y %x %c". The
NORMAL codes are described in the next section.
CODE NORMAL HEADER
%C pcpu %CPU
%G group GROUP
%P ppid PPID
%U user USER
%a args COMMAND
%c comm COMMAND
%g rgroup RGROUP
%n nice NI
%p pid PID
%r pgid PGID
%t etime ELAPSED
%u ruser RUSER
%x time TIME
%y tty TTY
%z vsz VSZ
STANDARD FORMAT SPECIFIERS
Here are the different keywords that may be used to control the output format (e.g. with
option
-o) or to sort the selected processes with the GNU-style
--sort option.
For example:
ps -eo pid,user,args --sort user
This version of
ps tries to recognize most of the keywords used in other implementations
of
ps.
The following user-defined format specifiers may contain spaces:
args,
cmd,
comm,
command,
fname,
ucmd,
ucomm,
lstart,
bsdstart,
start.
Some keywords may not be available for sorting.
CODE HEADER DESCRIPTION
%cpu %CPU cpu utilization of the process in "##.#" format. Currently, it is
the CPU time used divided by the time the process has been running
(cputime/realtime ratio), expressed as a percentage. It will not
add up to 100% unless you are lucky. (alias
pcpu).
%mem %MEM ratio of the process's resident set size to the physical memory on
the machine, expressed as a percentage. (alias
pmem).
args COMMAND command with all its arguments as a string. Modifications to the
arguments may be shown. The output in this column may contain
spaces. A process marked <defunct> is partly dead, waiting to be
fully destroyed by its parent. Sometimes the process args will be
unavailable; when this happens,
ps will instead print the executable
name in brackets. (alias
cmd,
command). See also the
comm format
keyword, the
-f option, and the
c option.
When specified last, this column will extend to the edge of the
display. If
ps can not determine display width, as when output is
redirected (piped) into a file or another command, the output width
is undefined (it may be 80, unlimited, determined by the
TERM
variable, and so on). The
COLUMNS environment variable or
--cols
option may be used to exactly determine the width in this case. The
w or
-w option may be also be used to adjust width.
blocked BLOCKED mask of the blocked signals, see signal(7). According to the width
of the field, a 32 or 64-bit mask in hexadecimal format is
displayed. (alias
sig_block,
sigmask).
bsdstart START time the command started. If the process was started less than 24
hours ago, the output format is " HH:MM", else it is " Mmm:SS"
(where Mmm is the three letters of the month). See also
lstart,
start,
start_time, and
stime.
bsdtime TIME accumulated cpu time, user + system. The display format is usually
"MMM:SS", but can be shifted to the right if the process used more
than 999 minutes of cpu time.
c C processor utilization. Currently, this is the integer value of the
percent usage over the lifetime of the process. (see
%cpu).
caught CAUGHT mask of the caught signals, see signal(7). According to the width
of the field, a 32 or 64 bits mask in hexadecimal format is
displayed. (alias
sig_catch,
sigcatch).
cgroup CGROUP display control groups to which the process belongs.
class CLS scheduling class of the process. (alias
policy,
cls). Field's
possible values are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
B SCHED_BATCH
ISO SCHED_ISO
IDL SCHED_IDLE
? unknown value
cls CLS scheduling class of the process. (alias
policy,
cls). Field's
possible values are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
B SCHED_BATCH
ISO SCHED_ISO
IDL SCHED_IDLE
? unknown value
cmd CMD see
args. (alias
args,
command).
comm COMMAND command name (only the executable name). Modifications to the
command name will not be shown. A process marked <defunct> is
partly dead, waiting to be fully destroyed by its parent. The
output in this column may contain spaces. (alias
ucmd,
ucomm). See
also the
args format keyword, the
-f option, and the
c option.
When specified last, this column will extend to the edge of the
display. If
ps can not determine display width, as when output is
redirected (piped) into a file or another command, the output width
is undefined (it may be 80, unlimited, determined by the
TERM
variable, and so on). The
COLUMNS environment variable or
--cols
option may be used to exactly determine the width in this case. The
w or
-w option may be also be used to adjust width.
command COMMAND See
args. (alias
args,
command).
cp CP per-mill (tenths of a percent) CPU usage. (see
%cpu).
cputime TIME cumulative CPU time, "[DD-]hh:mm:ss" format. (alias
time).
drs DRS data resident set size, the amount of physical memory devoted to
other than executable code.
egid EGID effective group ID number of the process as a decimal integer.
(alias
gid).
egroup EGROUP effective group ID of the process. This will be the textual group
ID, if it can be obtained and the field width permits, or a decimal
representation otherwise. (alias
group).
eip EIP instruction pointer.
esp ESP stack pointer.
etime ELAPSED elapsed time since the process was started, in the form
[[DD-]hh:]mm:ss.
etimes ELAPSED elapsed time since the process was started, in seconds.
euid EUID effective user ID (alias
uid).
euser EUSER effective user name. This will be the textual user ID, if it can be
obtained and the field width permits, or a decimal representation
otherwise. The
n option can be used to force the decimal
representation. (alias
uname, user
).
f F flags associated with the process, see the
PROCESS FLAGS section.
(alias
flag,
flags).
fgid FGID filesystem access group ID. (alias
fsgid).
fgroup FGROUP filesystem access group ID. This will be the textual group ID, if
it can be obtained and the field width permits, or a decimal
representation otherwise. (alias
fsgroup).
flag F see
f. (alias
f,
flags).
flags F see
f. (alias
f,
flag).
fname COMMAND first 8 bytes of the base name of the process's executable file.
The output in this column may contain spaces.
fuid FUID filesystem access user ID. (alias
fsuid).
fuser FUSER filesystem access user ID. This will be the textual user ID, if it
can be obtained and the field width permits, or a decimal
representation otherwise.
gid GID see
egid. (alias
egid).
group GROUP see
egroup. (alias
egroup).
ignored IGNORED mask of the ignored signals, see signal(7). According to the width
of the field, a 32 or 64 bits mask in hexadecimal format is
displayed. (alias
sig_ignore,
sigignore).
ipcns IPCNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
label LABEL security label, most commonly used for SELinux context data. This
is for the Mandatory Access Control ("MAC") found on high-security
systems.
lstart STARTED time the command started. See also
bsdstart,
start,
start_time,
and
stime.
lsession SESSION displays the login session identifier of a process, if systemd
support has been included.
lwp LWP light weight process (thread) ID of the dispatchable entity (alias
spid,
tid). See
tid for additional information.
machine MACHINE displays the machine name for processes assigned to VM or container,
if systemd support has been included.
maj_flt MAJFLT The number of major page faults that have occurred with this
process.
min_flt MINFLT The number of minor page faults that have occurred with this
process.
mntns MNTNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
netns NETNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
ni NI nice value. This ranges from 19 (nicest) to -20 (not nice to
others), see nice(1). (alias
nice).
nice NI see
ni.
(alias ni).
nlwp NLWP number of lwps (threads) in the process. (alias
thcount).
nwchan WCHAN address of the kernel function where the process is sleeping (use
wchan if you want the kernel function name). Running tasks will
display a dash ('-') in this column.
ouid OWNER displays the Unix user identifier of the owner of the session of a
process, if systemd support has been included.
pcpu %CPU see
%cpu. (alias
%cpu).
pending PENDING mask of the pending signals. See signal(7). Signals pending on the
process are distinct from signals pending on individual threads.
Use the
m option or the
-m option to see both. According to the
width of the field, a 32 or 64 bits mask in hexadecimal format is
displayed. (alias
sig).
pgid PGID process group ID or, equivalently, the process ID of the process
group leader. (alias
pgrp).
pgrp PGRP see
pgid. (alias
pgid).
pid PID a number representing the process ID (alias
tgid).
pidns PIDNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
pmem %MEM see
%mem. (alias
%mem).
policy POL scheduling class of the process. (alias
class,
cls). Possible
values are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
B SCHED_BATCH
ISO SCHED_ISO
IDL SCHED_IDLE
? unknown value
ppid PPID parent process ID.
pri PRI priority of the process. Higher number means lower priority.
psr PSR processor that process is currently assigned to.
rgid RGID real group ID.
rgroup RGROUP real group name. This will be the textual group ID, if it can be
obtained and the field width permits, or a decimal representation
otherwise.
rss RSS resident set size, the non-swapped physical memory that a task has
used (in kiloBytes). (alias
rssize,
rsz).
rssize RSS see
rss. (alias
rss,
rsz).
rsz RSZ see
rss. (alias
rss,
rssize).
rtprio RTPRIO realtime priority.
ruid RUID real user ID.
ruser RUSER real user ID. This will be the textual user ID, if it can be
obtained and the field width permits, or a decimal representation
otherwise.
s S minimal state display (one character). See section
PROCESS STATE
CODES for the different values. See also
stat if you want
additional information displayed. (alias
state).
sched SCH scheduling policy of the process. The policies SCHED_OTHER
(SCHED_NORMAL), SCHED_FIFO, SCHED_RR, SCHED_BATCH, SCHED_ISO, and
SCHED_IDLE are respectively displayed as 0, 1, 2, 3, 4, and 5.
seat SEAT displays the identifier associated with all hardware devices
assigned to a specific workplace, if systemd support has been
included.
sess SESS session ID or, equivalently, the process ID of the session leader.
(alias
session,
sid).
sgi_p P processor that the process is currently executing on. Displays "*"
if the process is not currently running or runnable.
sgid SGID saved group ID. (alias
svgid).
sgroup SGROUP saved group name. This will be the textual group ID, if it can be
obtained and the field width permits, or a decimal representation
otherwise.
sid SID see
sess. (alias
sess,
session).
sig PENDING see
pending. (alias
pending,
sig_pend).
sigcatch CAUGHT see
caught. (alias
caught,
sig_catch).
sigignore IGNORED see
ignored. (alias
ignored,
sig_ignore).
sigmask BLOCKED see
blocked. (alias
blocked,
sig_block).
size SIZE approximate amount of swap space that would be required if the
process were to dirty all writable pages and then be swapped out.
This number is very rough!
slice SLICE displays the slice unit which a process belongs to, if systemd
support has been included.
spid SPID see
lwp. (alias
lwp,
tid).
stackp STACKP address of the bottom (start) of stack for the process.
start STARTED time the command started. If the process was started less than 24
hours ago, the output format is "HH:MM:SS", else it is " Mmm dd"
(where Mmm is a three-letter month name). See also
lstart,
bsdstart,
start_time, and
stime.
start_time START starting time or date of the process. Only the year will be
displayed if the process was not started the same year
ps was
invoked, or "MmmDD" if it was not started the same day, or "HH:MM"
otherwise. See also
bsdstart,
start,
lstart, and
stime.
stat STAT multi-character process state. See section
PROCESS STATE CODES for
the different values meaning. See also
s and
state if you just want
the first character displayed.
state S see
s. (alias
s).
suid SUID saved user ID. (alias
svuid).
supgid SUPGID group ids of supplementary groups, if any. See
getgroups(2).
supgrp SUPGRP group names of supplementary groups, if any. See
getgroups(2).
suser SUSER saved user name. This will be the textual user ID, if it can be
obtained and the field width permits, or a decimal representation
otherwise. (alias
svuser).
svgid SVGID see
sgid. (alias
sgid).
svuid SVUID see
suid. (alias
suid).
sz SZ size in physical pages of the core image of the process. This
includes text, data, and stack space. Device mappings are currently
excluded; this is subject to change. See
vsz and
rss.
tgid TGID a number representing the thread group to which a task belongs
(alias
pid). It is the process ID of the thread group leader.
thcount THCNT see
nlwp. (alias
nlwp). number of kernel threads owned by the
process.
tid TID the unique number representing a dispatchable entity (alias
lwp,
spid). This value may also appear as: a process ID (pid); a
process group ID (pgrp); a session ID for the session leader (sid);
a thread group ID for the thread group leader (tgid); and a tty
process group ID for the process group leader (tpgid).
time TIME cumulative CPU time, "[DD-]HH:MM:SS" format. (alias
cputime).
tname TTY controlling tty (terminal). (alias
tt,
tty).
tpgid TPGID ID of the foreground process group on the tty (terminal) that the
process is connected to, or -1 if the process is not connected to a
tty.
trs TRS text resident set size, the amount of physical memory devoted to
executable code.
tt TT controlling tty (terminal). (alias
tname,
tty).
tty TT controlling tty (terminal). (alias
tname,
tt).
ucmd CMD see
comm. (alias
comm,
ucomm).
ucomm COMMAND see
comm. (alias
comm,
ucmd).
uid UID see
euid. (alias
euid).
uname USER see
euser. (alias
euser,
user).
unit UNIT displays unit which a process belongs to, if systemd support has
been included.
user USER see
euser. (alias
euser,
uname).
userns USERNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
utsns UTSNS Unique inode number describing the namespace the process belongs to.
See namespaces(7).
uunit UUNIT displays user unit which a process belongs to, if systemd support
has been included.
vsize VSZ see
vsz. (alias
vsz).
vsz VSZ virtual memory size of the process in KiB (1024-byte units). Device
mappings are currently excluded; this is subject to change. (alias
vsize).
wchan WCHAN name of the kernel function in which the process is sleeping, a "-"
if the process is running, or a "*" if the process is multi-threaded
and
ps is not displaying threads.
ENVIRONMENT VARIABLES
The following environment variables could affect
ps:
COLUMNS
Override default display width.
LINES
Override default display height.
PS_PERSONALITY
Set to one of posix, old, linux, bsd, sun, digital... (see section
PERSONALITY below).
CMD_ENV
Set to one of posix, old, linux, bsd, sun, digital... (see section
PERSONALITY below).
I_WANT_A_BROKEN_PS
Force obsolete command line interpretation.
LC_TIME
Date format.
PS_COLORS
Not currently supported.
PS_FORMAT
Default output format override. You may set this to a format string of the type used
for the
-o option. The
DefSysV and
DefBSD values are particularly useful.
PS_SYSMAP
Default namelist (System.map) location.
PS_SYSTEM_MAP
Default namelist (System.map) location.
POSIXLY_CORRECT
Don't find excuses to ignore bad "features".
POSIX2
When set to "on", acts as
POSIXLY_CORRECT.
UNIX95
Don't find excuses to ignore bad "features".
_XPG
Cancel
CMD_ENV=irix non-standard behavior.
In general, it is a bad idea to set these variables. The one exception is
CMD_ENV or
PS_PERSONALITY, which could be set to Linux for normal systems. Without that setting,
ps
follows the useless and bad parts of the Unix98 standard.
PERSONALITY
390 like the OS/390 OpenEdition
ps
aix like AIX
ps
bsd like FreeBSD
ps (totally non-standard)
compaq like Digital Unix
ps
debian like the old Debian
ps
digital like Tru64 (was Digital Unix, was OSF/1)
ps
gnu like the old Debian
ps
hp like HP-UX
ps
hpux like HP-UX
ps
irix like Irix
ps
linux *****
recommended *****
old like the original Linux
ps (totally non-standard)
os390 like OS/390 Open Edition
ps
posix standard
s390 like OS/390 Open Edition
ps
sco like SCO
ps
sgi like Irix
ps
solaris2 like Solaris 2+ (SunOS 5)
ps
sunos4 like SunOS 4 (Solaris 1)
ps (totally non-standard)
svr4 standard
sysv standard
tru64 like Tru64 (was Digital Unix, was OSF/1)
ps
unix standard
unix95 standard
unix98 standard
SEE ALSO
pgrep(1),
pstree(1),
top(1),
proc(5).
STANDARDS
This
ps conforms to:
1 Version 2 of the Single Unix Specification
2 The Open Group Technical Standard Base Specifications, Issue 6
3 IEEE Std 1003.1, 2004 Edition
4 X/Open System Interfaces Extension [UP XSI]
5 ISO/IEC 9945:2003
AUTHOR
ps was originally written by Branko Lankester ⟨⟩. Michael K. Johnson
⟨⟩ re-wrote it significantly to use the proc filesystem, changing a few
things in the process. Michael Shields ⟨⟩ added the pid-list
feature. Charles Blake ⟨⟩ added multi-level sorting, the dirent-style
library, the device name-to-number mmaped database, the approximate binary search directly
on System.map, and many code and documentation cleanups. David Mossberger-Tang wrote the
generic BFD support for psupdate. Albert Cahalan ⟨⟩ rewrote ps for
full Unix98 and BSD support, along with some ugly hacks for obsolete and foreign syntax.
Please send bug reports to ⟨⟩. No subscription is required or
suggested.