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justin@Justin:~$ ps --help
********* simple selection *********  ********* selection by list *********
-A all processes                      -C by command name
-N negate selection                   -G by real group ID (supports names)
-a all w/ tty except session leaders  -U by real user ID (supports names)
-d all except session leaders         -g by session OR by effective group name
-e all processes                      -p by process ID
T  all processes on this terminal     -s processes in the sessions given
a  all w/ tty, including other users  -t by tty
g  OBSOLETE -- DO NOT USE             -u by effective user ID (supports names)
r  only running processes             U  processes for specified users
x  processes w/o controlling ttys     t  by tty
*********** output format **********  *********** long options ***********
-o,o user-defined  -f full            --Group --User --pid --cols --ppid
-j,j job control   s  signal          --group --user --sid --rows --info
-O,O preloaded -o  v  virtual memory  --cumulative --format --deselect
-l,l long          u  user-oriented   --sort --tty --forest --version
-F   extra full    X  registers       --heading --no-heading --context
                    ********* misc options *********
-V,V  show version      L  list format codes  f  ASCII art forest
-m,m,-L,-T,H  threads   S  children in sum    -y change -l format
-M,Z  security data     c  true command name  -c scheduling class
-w,w  wide output       n  numeric WCHAN,UID  -H process hierarchy

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 -eopid,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 -p 42 -o comm=

Displayed Info

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, either by a job control signal or because it is being traced. 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

Feilds

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-bit 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 dd" (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).

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, class). 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, cmd).

cp CP per-mill (tenths of a percent) CPU usage. (see %cpu).

cputime TIME cumulative CPU time, "[dd-]hh:mm:ss" format. (alias time).

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.

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 user 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-bit or 64-bit mask in hexadecimal format is displayed. (alias sig_ignore,
sigignore).

label LABEL security label, most commonly used for SE Linux 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.

lwp LWP lwp (light weight process, or thread) ID of the lwp being reported.
(alias spid, tid).

maj_flt MAJFLT The number of major page faults that have occured with this process.

min_flt MINFLT The number of minor page faults that have occured with this process.

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.

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-bit or 64-bit 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 process ID number of the process.

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.

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!

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 gid of supplementary groups, see getgroups(2).

supgrp SUPGRP names of supplementary groups, 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.

thcount THCNT see nlwp. (alias nlwp). number of kernel threads owned by the process.

tid TID see lwp. (alias lwp).

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.

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).

user USER see euser. (alias euser, uname).

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.