ps Command

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Purpose

Shows status of processes. This document describes the standard AIX® ps command as well as the System V version of the ps command.

Syntax

X/Open Standards

ps [ -A ] [ -M ] [ -N ] [ -Z ] [ -a ] [ -d ] [ -e ] [ -f ] [ -k ] [ -l ] [ -F format] [ -o Format ] [ -c Clist ] [ -G Glist ] [ -g Glist ] [ -m ] [ -n NameList ] [ -p Plist ] [ -P ] [ -t Tlist ] [ -U Ulist ] [ -u Ulist ] [ -T pid ] [ -L pidlist ] [ -X ] [ -@ [ WparName ] ]

Berkeley Standards

ps [ a ] [ c ] [ e ] [ ew ] [ eww ] [ ewww ] [ g ] [ n ] [ w ] [ x ] [ l | s | u | v ] [ t tty ] [ X ] [ ProcessNumber ]

Description

The ps command writes the status of active processes and if the -m flag is given, displays the associated kernel threads to standard output. While the -m flag displays threads associated with processes using extra lines, you must use the -o flag with the THREAD field specifier to display extra thread-related columns.

Without flags, the ps command displays information about the current terminal. The -f, -o, l, -l, s, u, and v flags only determine how much information is provided about a process; they do not determine which processes are listed. The l, s, u, and v flags are mutually exclusive.

With the -o flag, the ps command examines memory or the paging area and determines what the command name and parameters were when the process was created. If the ps command cannot find this information, the command name stored in the kernel is displayed in square brackets.

The COLUMNS environment variable overrides the system-selected, horizontal screen size.

The command-line flags that accept a list of parameters (the -o, -G, -g, -p, -t, -U, and -u flags) are limited to 128 items. For example, the -u Ulist flag can specify no more than 128 users.

For cases in which the output of the ps command does not include workload partition (WPAR) names but does include Project IDs (PROJECT), User IDs (UID or USER), or Group IDs (GID) associated with a process running within a workload partition under the current operating environment, the IDs are preceded by a plus sign (+) to indicate the association with a workload partition. Each workload partition contains its own definition of users, groups, and project IDs that may be different from the IDs defined for the global environment. The -@ option may be specified to include workload partition names in the output.

Note: The ps command does not show the decrease in the memory usage count when the application releases the memory. When the memory is released from the application, the memory is assigned to the per process memory freelist. The ps command accounts the memory that is released as the allocated memory for the application.

Depending on the flags used with the ps command, column headings are displayed above the information displayed to standard output. The headings are defined in the following list and the flags that cause these headings to be displayed are shown in parentheses :

ADDR
(-l and l flags) Contains the segment number of the process stack, if normal; if a kernel process, the address of the preprocess data area.
BND
(-o THREAD flag) The logical processor number of the processor to which the kernel thread is bound if any. For a process, this field is displayed if all its threads are bound to the same processor.
C
(-f, l, and -l flags) CPU utilization of process or thread, incremented each time the system clock ticks and the process or thread is found to be running. The value is decayed by the scheduler by dividing it by 2 once per second. For the sched_other policy, CPU utilization is used in determining process scheduling priority. Large values indicate a CPU intensive process and result in lower process priority, whereas small values indicate an I/O intensive process and result in a more favorable priority.
CMD
(-f, -l, and l flags) Contains the command name. Under the -f flag, the ps command tries to determine the current command name and arguments, both of which may be changed asynchronously by the process. These are then displayed. If this fails, the command name is written as it would appear without the -f option in square brackets.
COMMAND
(s, u, and v) Contains the command name. The full command name and its parameters are displayed with the -f flag.
F Field Table
Flags Hexadecimal Value Definition
SLOAD 0x00000001 Indicates that the process is operating in core memory.
SNOSWAP 0x00000002 Indicates that the process cannot be swapped out.
STRC 0x00000008 Indicates that the process is being traced.
SWTED 0x00000010 Indicates that the process stopped while being traced.
SFWTED 0x00000020 Indicates that the process stopped after a call to the fork subroutine, while being traced.
SEWTED 0x00000040 Indicates that the process stopped after a call to the exec subroutine, while being traced.
SLWTED 0x00000080 Indicates that the process stopped after a call to the load or unload subroutine, while being traced.
SFIXPRI 0x00000100 Indicates that the process has a fixed priority, ignoring the pcpu field descriptor.
SKPROC 0x00000200 Indicates a Kernel process.
SOMASK 0x00000400 Indicates restoration of the old mask after a signal is received.
SWAKEONSIG 0x00000800 Indicates that the signal will abort the sleep subroutine. The contents must not be equal to those of the PCATCH flag. The contents of both PCATCH and SWAKEONSIG must be greater than those of PMASK.
SUSER 0x00001000 Indicates that the process is in user mode.
SLKDONE 0x00002000 Indicates that the process has done locks.
STRACING 0x00004000 Indicates that the process is a debugging process.
SMPTRACE 0x00008000 Indicates multi-process debugging.
SEXIT 0x00010000 Indicates that the process is exiting.
SSEL 0x00020000 Indicates that the processor is selecting: wakeup/waiting danger.
SORPHANPGRP 0x00040000 Indicates an orphaned process group.
SNOCNTLPROC 0x00080000 Indicates that the session leader relinquished the controlling terminal.
SPPNOCLDSTOP 0x00100000 Indicates that the SIGHLD signal is not sent to the parent process when a child stops.
SEXECED 0x00200000 Indicates that process has been run.
SJOBSESS 0x00400000 Indicates that job control was used in the current session.
SJOBOFF 0x00800000 Indicates that the process is free from job control.
PSIGDELIVERY 0x01000000 Indicates that the process is used by the program-check handler.
SRMSHM 0x02000000 Indicates that the process removed shared memory during a call to the exit subroutine.
SSLOTFREE 0x04000000 Indicates that the process slot is free.
SNOMSG 0x08000000 Indicates that there are no more uprintf subroutine messages.
WPAR
(-@ flag) Contains the workload partition name. Under the -@ flag, the ps command displays the name of the workload partition in which the process is running. Specify the -@ flag with the wparname parameter to display the process information.
DPGSZ
(Z flag) The data page size of the process.
F
(-l and l flags) Some of the more important F field flags (hexadecimal and additive) associated with processes and threads are listed in the following table:
F Field Table
Flags Hexadecimal Value Definition
SLOAD 0x00000001 Indicates that the process is operating in core memory.
SNOSWAP 0x00000002 Indicates that the process cannot be swapped out.
STRC 0x00000008 Indicates that the process is being traced.
SKPROC 0x00000200 Indicates a kernel process.
SEXIT 0x00010000 Indicates that the process is exiting.
SLPDATA 0x00020000 Indicates that the process uses large pages.
SEXECED 0x00200000 Indicates that the process has been run.
SEXECING 0x01000000 Indicates that the process is execing (performing an exec).
SPSEARLYALLOC 0x04000000 Indicates that paging space for this process is allocated early.
TKTHREAD 0x00001000 Indicates that the thread is a kernel-only thread.
Note: You can see the definitions of all process and thread flags by consulting the p_flags and t_flags fields in the /usr/include/sys/proc.h and /usr/include/sys/thread.h files respectively.
LIM
(v flag) The soft limit on memory used, specified through a call to the setrlimit subroutine. If the limit has not been specified, then xx is displayed. If the limit is set to the system limit (unlimited), a value of UNLIM is displayed.
NI
(-l and l flags) The nice value; used in calculating priority for the sched other policy.
PID
(all flags) The process ID of the process.
PGIN
(v flag) The number of disk I/Os resulting from references by the process to pages not loaded in core.
PPID
(-f, l, and -l flags) The process ID of the parent process.
PRI
(-l and l flags) The priority of the process or kernel thread; higher numbers mean lower priority.
PROJECT
(-P flag) Project name assigned to the process. Under the current operating environment, the PROJECT and USER fields are not translated to names for processes running within a workload partition. The -U and -u flags only apply to the current operating environment, unless the -@ flag is included with a specific workload partition name. If the -@ flag is used to specify a workload partition other than the current operating environment, and the -U and -u flags are specified, the list of user IDs must be numeric.
RSS
(v flag) The real-memory (resident set) size of the process (in 1 KB units).
S
(-l and l flags) The state of the process or kernel thread :

For processes:

O
Nonexistent
A
Active
W
Swapped
I
Idle (waiting for startup)
Z
Canceled
T
Stopped

For kernel threads:

O
Nonexistent
R
Running
S
Sleeping
W
Swapped
Z
Canceled
T
Stopped
SC
(-o THREAD flag) The suspend count of the process or kernel thread. For a process, the suspend count is defined as the sum of the kernel threads suspend counts.
SCH
(-o THREAD, sched flag) The scheduling policy for a kernel thread. The policies sched_other, sched_fifo, and sched_rr are respectively displayed using: 0, 1, 2. The scheduling policies is displayed only when a sched flag is specified.
SIZE
(v flag) The virtual size of the data section of the process (in 1 KB units).
SHMPGSZ
(Z flag) The shared memory page size of the process.
SPGSZ
(Z flag) The stack page size of the process.
SSIZ
(s flag) The size of the kernel stack. This value is always 0 (zero) for a multi-threaded process.
STAT
(s, u, and v flags) Contains the state of the process:
0
Nonexistent
A
Active
I
Intermediate
Z
Canceled
T
Stopped
K
Available kernel process
STIME
(-f and u flags) The starting time of the process. The LANG environment variables control the appearance of this field.
SUBPROJ
(-P flag) Subproject Identifier assigned to the process.
SZ
(-l and l flags) The size in 1 KB units of the core image of the process.
THCNT
(-o thcount flag) The number of kernel threads owned by the process.
TID
(-o THREAD flag) The thread ID of the kernel thread.
TIME
(all flags) The total runtime for the process. The time is displayed in the format of mm:ss or mmmm:ss if the runtime reaches 100 minutes, which is different from the displayed format if you use the -o time flag.
TPGSZ
(Z flag) The text page size of the process.
TRS
(v flag) The size of resident-set (real memory) of text.
TSIZ
(v flag) The size of text (shared-program) image.
TTY
(all flags) The controlling terminal for the process:
-
The process is not associated with a terminal.
?
Unknown.
Number
The TTY number. For example, the entry 2 indicates TTY2.
UID
(-f, -l, and l flags) The user ID of the process owner. The login name is printed under the -f flag.
USER
(u flag) The login name of the process owner. Under the current operating environment, the PROJECT and USER fields are not translated to names for processes running within a workload partition.
WCHAN
(-l flag) The event for which the process or kernel thread is waiting or sleeping. For a kernel thread, this field is blank if the kernel thread is running. For a process, the wait channel is defined as the wait channel of the sleeping kernel thread if only one kernel thread is sleeping; otherwise a star is displayed.
WCHAN
(l flag) The event on which the process is waiting (an address in the system). A symbol that classifies the address is selected, unless a numerical output is requested.
%CPU
(u and v flags) The percentage of time the process has used the CPU since the process started. This value is computed by dividing the time the process uses the CPU by the elapsed time of the process. In a multi-processor environment, the value is further divided by the number of available CPUs because several threads in the same process can run on different CPUs at the same time. (Because the time base over which this data is computed varies, the sum of all %CPU fields can exceed 100%.)
%MEM
(u and v flags) The percentage of real memory used by this process. The %MEM value tends to exaggerate the cost of a process that is sharing program text with other processes. It does not account for times when multiple copies of a program are run and a copy of the program text is shared by all instances. The size of the text section is accounted for in every instance of the program. This means that if several copies of a program are run, the total %MEM value of all processes could exceed 100%.
A process that has exited and has a parent that has not yet waited for the process is marked <defunct>. A process that is blocked trying to exit is marked <exiting>. The ps command attempts to determine the file name and arguments given when the process was created by memory or by the swap area.
Notes:
  1. The process can change while the ps command is running. Some data displayed for defunct processes is irrelevant.
  2. The ps program examines the memory to retrieve the file name and arguments used when the process was created. However, a process can destroy information, making this method of retrieving file name and arguments unreliable.
  3. The ps program searches the local resources for users and group information.

Flags

The following flags are preceded by a - (minus sign):

Item Description
-A Writes to standard output information about all processes.
-a Writes to standard output information about all processes, except the session leaders and processes not associated with a terminal.
-c Clist Displays only information about processes assigned to the workload management classes listed in the Clist variable. The Clist variable is either a comma-separated list of class names or a list of class names enclosed in double quotation marks (" "), which is separated from one another by a comma or by one or more spaces, or both.
-d Writes information to standard output about all processes, except the session leaders.
-e Writes information to standard output about all processes, except kernel processes.
-F Format Same as the -o Format
-f Generates a full listing.
-G Glist Writes information to standard output only about processes that are in the effective groups listed for the Glist variable. The Glist variable is either a comma-separated list of effective group identifiers, or a list of effective group identifiers enclosed in double quotation marks (" ") and separated from one another by a comma or by one or more spaces.
-g Glist Writes information to standard output only about processes that are in the process groups listed for the Glist variable. The Glist variable is either a comma-separated list of process group identifiers or a list of process group identifiers enclosed in double quotation marks (" ") and separated from one another by a comma or by one or more spaces.
-k Lists kernel processes.
-l Generates a long listing. Also see the l flag.
-L pidlist Generates a list of descendants of each and every pid that has been passed to it in the pidlist variable. The pidlist variable is a list of comma-separated process IDs. The list of descendants from all the given pid is printed in the order in which they appear in the process table.
-M Lists all 64 bit processes.
-m Lists kernel threads as well as processes. Output lines for processes are followed by an additional output line for each kernel thread. This flag does not display thread-specific fields (bnd, scount, sched, thcount, and tid), unless the appropriate -o Format flag is specified.
-N Gathers no thread statistics. With this flag, ps reports those statistics that can be obtained by not traversing through the threads chain for the process.
-n NameList Specifies an alternative system name-list file in place of the default. The operating system does not use the -n flag because information is supplied directly to the kernel.
-o Format Displays information in the format specified by the Format variable. Multiple field specifiers can be specified for the Format variable. The Format variable is either a comma-separated list of field specifiers or a list of field specifiers enclosed within a set of " " (double-quotation marks) and separated from one another by a comma or by one or more spaces, or both.

Each field specifier has a default header. The default header can be overridden by appending an = (equal sign) followed by the user-defined text for the header. The fields are written in the order specified on the command-line in column format. The field widths are specified by the system to be at least as wide as the default or user-defined header text. If the header text is null (such as if -o user= is specified), the field width is at least as wide as the default header text. If all header fields are null, no header line is written.

The following field specifiers are recognized by the system:

args
Indicates the full command name being executed. All command-line arguments are included, though truncation may occur. The default header for this field is COMMAND.
bnd
Indicates to which (if any) processor a process or kernel thread is bound. The default header for this field is BND.
class
Indicates the workload management class assigned to the process or thread. The default header for this field is CLASS.
comm
Indicates the short name of the command being executed. Command-line arguments are not included. The default header for this field is COMMAND.
cpu
Determines process scheduling priority. CPU utilization of a process or thread, incremented each time the system clock ticks and the process or thread is found to be running. The value is decayed by the scheduler by dividing it by 2 once per second. For the sched_other policy, Large values indicate a CPU intensive process and result in lower process priority whereas small values indicate an I/O intensive process and result in a more favorable priority.
dpgsz
Indicates the data page size of a process.
etime
Indicates the elapsed time since the process started. The elapsed time is displayed in the following format:

[[ dd-]hh:]mm:ss

where dd specifies the number of days, hh specifies the number of hours, mm specifies the number of minutes, and ss specifies the number of seconds. The default header for this field is ELAPSED.

group
Indicates the effective group ID of the process. The textual group ID is displayed. If the textual group ID cannot be obtained, a decimal representation is used. The default header for this field is GROUP.
nice
Indicates the decimal value of the process nice value. The default header for this field is NI.
-o Continued
pcpu
Indicates the ratio of CPU time used to CPU time available, expressed as a percentage. The default header for this field is %CPU.
pgid
Indicates the decimal value of the process group ID. The default header for this field is PGID.
pid
Indicates the decimal value of the process ID. The default header for this field is PID.
ppid
Indicates the decimal value of the parent process ID. The default header for this field is PPID.
rgroup
Indicates the real group ID of the process. The textual group ID is displayed. If the textual group ID cannot be obtained, a decimal representation is used. The default header for this field is RGROUP.
ruser
Indicates the real user ID of the process. The textual user ID is displayed. If the textual user ID cannot be obtained, a decimal representation is used. The default header for this field is RUSER.
scount
Indicates the suspend count for a kernel thread. The default header for this field is SC.
sched
Indicates the scheduling policy for a kernel thread. The default header for this field is SCH.
shmpgsz
Indicates the shared memory page size of a process.
spgsz
Indicates the stack page size of a process.
tag
Indicates the Workload Manager application tag. The default header for this field is TAG. The tag is a character string up to 30 characters long and may be truncated when displayed by ps. For processes that do not set their tag, this field displays as a - (hyphen).
tcpu
Total CPU time. Indicates the total accumulated CPU time for a single process. The command displays the information when WLM is running either in active or passive mode else, this field displays as a - (hyphen). The default header for this field is TCPU.
-oContinued
tctime
Total connect time. Indicates the total amount of time that a login session can be active. This is meaningful only in the case of session leader processes. The default header for this field is TCTIME.
tdiskio
Total disk I/O. Indicates the total accumulated blocks of disk I/O for a single process. The default header for this field is TDISKIO.
tpgsz
Indicates the text page size of a process.
vmsize
Indicates the WLM virtual memory limits. When this is used, a new header, VMSIZ is displayed. VMSIZ displays the virtual memory used by the process. This value is displayed in 1 MB units.
thcount
Indicates the number of kernel threads owned by the process. The default header for this field is THCNT.
-o Continued
THREAD
Indicates the following fields:
  • User name (the uname field)
  • Process and parent process IDs for processes (the pid and ppid fields)
  • Kernel thread ID for threads (the tid field)
  • The state of the process or kernel thread (the S field)
  • The CPU utilization of the process or kernel thread (the C field)
  • The priority of the process or kernel thread (the PRI field)
  • The suspend count of the process or kernel thread (the scount field)
  • The wait channel of the process or kernel thread (the WCHAN field)
  • The flags of the process or kernel thread (the F field)
  • The controlling terminal of the process (the tty field)
  • The CPU to which the process or kernel thread is bound (the bnd field)
  • The command being executed by the process (the comm field).

Threads are not displayed with the -o THREAD flag, unless the -m flag is also specified.

Note: The ps -o THREAD flag does not print the scheduler policies. The scheduling policies are displayed only when a sched flag is specified.
tid
Indicates the thread ID of a kernel thread. The default header for this field is TID.
time
Indicates the cumulative CPU time since the process started. The time is displayed in the following format:

[ dd-] hh:mm:ss

where dd specifies the number of days, hh specifies the number of hours, mm specifies the number of minutes, and ss specifies the number of seconds. The default header for this field is TIME.

tty
Indicates the controlling terminal name of the process. The default header for this field is TT.
user
Indicates the effective user ID of the process. The textual user ID is displayed. If the textual user ID cannot be obtained, a decimal representation is used. The default header for this field is USER.
vsz
Indicates, as a decimal integer, the size in kilobytes of the process in virtual memory. The default header for this field is VSZ.

Otherwise, multiple fields in a specified format can be displayed by the Format variable, including field descriptors. If field descriptors are used in the Format variable, it must be enclosed in double quotation marks (" "). The following table shows how field descriptors correspond to field specifiers:
  
Field           Field           Default 
Descriptors     Specifiers      Headers
%a              args            COMMAND
%c              comm            COMMAND
%t              etime           ELAPSED
%D              dpgsz           DPGSZ
%G              group           GROUP
%n              nice            NI
%C              pcpu            %CPU
%r              pgid            PGID
%p              pid             PID
%P              ppid            PPID
%g              rgroup          RGROUP
%u              ruser           RUSER
%S              spgsz           SPGSZ
%x              time            TIME
%T              tpgsz           TPGSZ gd
%y              tty             TTY
%U              user            USER
%z              vsz             VSZ

Each field specifier has a default header. The default header can be overridden by appending an equal sign (=) followed by the user-defined text for the header. The fields are written in the order specified on the command-line in column format. The field widths are specified by the system to be at least as wide as the default or user-defined header text. If the header text is null (for example, -o user= is specified), the field width is at least as wide as the default header text. If all header fields are null, no header line is written.
 
Following is the mapping between the default headers and various field specifiers. Every entry in the Default Header column can be overridden by appending an equal sign (=) to the corresponding entry in the Field specifier followed by the user-defined text for the header. 
Default Header                 Field specifier

ARGS                          "args"
COMM                          "comm"
COMM                          "command"
COMM                          "ucomm"
F_ETIME                       "etime"
GROUP                         "group"
GROUP                         "gname"
GID                           "gid"
NICE                          "nice"
PRI                           "pri"
NICE                          "ni"
PCPU                          "pcpu"
PMEM                          "pmem"
PGID                          "pgid"
PID                           "pid"
PPID                          "ppid"
RGROUP                        "rgroup"
RGROUP                        "rgname"
RGID                          "rgid"
RUSER                         "ruser"
RUSER                         "runame"
RUID                          "ruid"
TIME                          "time"
TIME                          "cputime"
TTY                           "tty"
TTY                           "tt"
TTY                           "tname"
TTY                           "longtname"
USER                          "user"
USER                          "uname"
UID                           "uid"
LOGNAME                       "logname"
STIME                         "start"
VSZ                           "vsz"
VSZ                           "vsize"
RSS                           "rssize"
FLAG                          "flag"
STATUS                        "status"
CP                            "cp"
PAGEIN                        "pagein"
WCHAN                         "wchan"
NWCHAN                        "nwchan"
ST                            "st"
TID                           "tid"
SCOUNT                        "scount"
BIND                          "bnd"
SCHED                         "sched"
THCOUNT                        "thcount"
TAG                           "tag"
CLASS                         "class"
TCPU                          "tcpu"
TDISKIO                       "tdiskio"
TCTIME                        "tctime"
MACLAB                        "mac"
-p Plist Displays only information about processes with the process numbers specified for the Plist variable. The Plist variable is either a comma-separated list of process ID numbers or a list of process ID numbers enclosed in double quotation marks (" ") and separated from one another by a comma or by one or more spaces, or both.
-P Displays the Project name, Project origin, and subproject identifier for the project. If the stick bit is set for the process, the project name is preceded by an asterisk (*) character. The Project origin field designates the currently loaded project repository (LOCAL or LDAP).
-t Tlist Displays only information about processes associated with the controlling ttys listed in the Tlist variable. The Tlist variable is either a comma-separated list of tty identifiers or a list of tty identifiers enclosed in double quotation marks (" ") and separated from one another by a comma or by one or more spaces, or both.
-T pid Displays the process hierarchy rooted at a given pid in a tree format using ASCII art. This flag can be used in combination with the -f, -F, -o, and -l flags.
-u Ulist This flag is equivalent to the -U Ulist flag. The -u flag only applies to the current operating environment unless the -@ flag is also specified. If the -@ flag is used to specify a workload partition other than the current operating environment and the -u flag is specified, the list of user IDs must be numeric.
-U Ulist Displays only information about processes with the user ID numbers or login names specified for the Ulist variable. The Ulist variable is either a comma-separated list of user IDs or a list of user IDs enclosed in double quotation marks (" ") and separated from one another by a comma and one or more spaces. The -U flag only applies to the current operating environment unless the -@ flag is also specified. If the -@ flag is used to specify a workload partition other than the current operating environment and the -U flag is specified, the list of user IDs must be numeric. In the listing, the ps command displays the numerical user ID unless the -f flag is used; then the command displays the login name. This flag is equivalent to the -u Ulist flag. See also the u flag.
-X Prints all available characters of each user/group name instead of truncating to the first eight characters.
-Z Displays the page size settings of processes.
DPGSZ
Indicates the data page size of a process.
SHMPGSZ
Indicates the shared memory page size the process allocates.
SPGSZ
Indicates the stack page size of a process.
TPGSZ
Indicates the text page size of a process.
-@ [ WparName ] Displays the process information that is associated with the workload partition WparName. If you do not specify the WparName parameter, the process information for all workload partitions is displayed. Workload partition information is displayed for all processes. You must specify other flags to the ps command to determine which process information to be displayed.

Options

The following options are not preceded by a minus sign (-):

Item Description
a Displays information about all processes with terminals (ordinarily only the own processes of the user are displayed).
c Displays the command name, as stored internally in the system for purposes of accounting, rather than the command parameters, which are kept in the process address space.
e Displays the environment as well as the parameters to the command, up to a limit of 80 characters.
ew Wraps the display from the e flag one extra line.
eww Wraps the display from the e flag and displays the ENV list until the flag reaches the LINE_MAX value.
ewww Wraps the display from the e flag and displays the ENV list until the flag reaches the INT_MAX value.
g Displays all processes.
l Displays a long listing having the F, S, UID, PID, PPID, C, PRI, NI, ADDR, SZ, PSS, WCHAN, TTY, TIME, and CMD fields.
n Displays numerical output. In a long listing, the WCHAN field is printed numerically rather than symbolically. In a user listing, the USER field is replaced by a UID field.
s Displays the size (SSIZ) of the kernel stack of each process (for use by system maintainers) in the basic output format. This value is always 0 (zero) for a multi-threaded process.
t tty Displays processes whose controlling tty is the value of the tty variable, which should be specified as printed by the ps command; that is, 0 for terminal /dev/tty/0, lft0 for /dev/lft0, and pts/2 for /dev/pts/2.
u Displays user-oriented output. This includes the USER, PID, %CPU, %MEM, SZ, RSS, TTY, STAT, STIME, TIME, and COMMAND fields.
v Displays the PGIN, SIZE, RSS, LIM, TSIZ, TRS, %CPU, %MEM fields.
w Specifies a wide-column format for output (132 columns rather than 80). If repeated, (for example, ww), uses arbitrarily wide output. This information is used to decide how much of long commands to print.
x Displays processes without a controlling terminal in addition to processes with a controlling terminal.
X Prints the full user name or group name. The name is not truncated.

Exit Status

This command returns the following exit values:

Item Description
0 Successful completion.
>0 An error occurred.

Security

Attention RBAC users and Trusted AIX users: This command can perform privileged operations. Only privileged users can run privileged operations. For more information about authorizations and privileges, see Privileged Command Database in Security. For a list of privileges and the authorizations associated with this command, see the lssecattr command or the getcmdattr subcommand.

Examples

  1. To display all processes, type: 
    ps -e -f
    To display all processes with expanded user name, type: 
    ps -X -e -f
  2. To list processes owned by specific users, type: 
    ps -f -l -ujim,jane,su
  3. To list processes that are associated with the /dev/console and /dev/tty1 ttys, type: 
    ps -t console,tty/1
  4. To list processes not associated with a terminal, type: 
    ps -t -
  5. To display a specified format with field specifiers, type: 
    ps -o ruser,pid,ppid=parent,args
    The output is: 
    RUSER   PID     parent  COMMAND
helene  34      12      ps -o ruser,pid,ppid=parent,args
  6. To display a specified format with field descriptors, type: 
    ps -o "< %u > %p %y : %a"
    The output is: 
    < RUSER  >      PID     TT :    COMMAND
< helene >      34      pts/3 : ps -o < %u > %p %y : %a
  7. To display information about processes and kernel threads controlled by the current terminal, type: 
    ps -lm
    The output is like: 
         F S UID  PID PPID  C PRI NI ADDR  SZ WCHAN   TTY  TIME  CMD
240003 A  26 8984 7190  1  60 20 2974 312       pts/1  0:00  -ksh
   400 S   -    -    -  1  60  -    -   -           -     -  -
200005 A  26 9256 8984 15  67 20 18ed 164       pts/1  0:00  ps
     0 R   -    -    - 15  67  -    -   -           -     -  -
  8. To display information about all processes and kernel threads, type: 
    ps -emo THREAD
    The output is like: 
    USER   PID  PPID  TID S  C PRI SC   WCHAN   FLAG   TTY BND  CMD
jane  1716 19292    - A 10  60  1       * 260801 pts/7   -  biod
   -     -     - 4863 S  0  60  0 599e9d8   8400     -   -  -
   -     -     - 5537 R 10  60  1 5999e18   2420     -   3  -
luke 19292 18524    - A  0  60  0 586ad84 200001 pts/7   -  -ksh
   -     -     - 7617 S  0  60  0 586ad84    400     -   -  -
luke 25864 31168    - A 11  65  0       - 200001 pts/7   -  -
   -     -     - 8993 R 11  65  0       -      0     -   -  -
  9. To list all the 64-bit processes, type: 
    ps -M
  10. To display the project assignment details for the processes, type: 
    ps -P
  11. To display the page size settings of the processes, type: 
    ps -Z
    The output is like: 
              PID    TTY TIME DPGSZ SPGSZ TPGSZ SHMPGSZ CMD
        41856 pts/15 0:00    4K    4K    4K    64K    ps
        84516 pts/15 0:00    4K    4K    4K    64K    ksh

Files

Item Description
/usr/bin/ps Contains the ps command.

Using the ps command in Performance management.

System V ps command

Syntax (System V)

/usr/sysv/bin/ps [ -a ] [ -A ] [ -c ] [ -d ] [ -e ] [ -f ] [ -j ] [ -l ] [ -L ] [ -P ] [ -y ] [ -g pgrplist ] [ -o format ] [ -p proclist ] [ -s sidlist ] [ -t termlist ] [ { -u | -U } uidlist ] [ -G grplist ] [ -X ]

Description (System V)

The ps command prints information about active processes. Without flags, ps prints information about processes associated with the controlling terminal. The output contains the process ID, terminal identifier, cumulative runtime, and the command name. The information displayed with flags varies accordingly.

Output

Depending on the flags used with the ps command, column headings vary for the information displayed. The headings are defined in the following list (flags that cause these headings to appear are shown in parentheses):

F (-l)
Flags (hexadecimal and additive) associated with the process, or the thread if the -L option is specified. Some of the more important F field flags (hexadecimal and additive) associated with processes and threads are shown below:
F Field Table
Flags Hexadecimal Value Definition
SLOAD 0x00000001 Indicates that the process is operating in core memory.
SNOSWAP 0x00000002 Indicates that the process cannot be swapped out.
STRC 0x00000008 Indicates that the process is being traced.
SKPROC 0x00000200 Indicates a Kernel process.
SEXIT 0x00010000 Indicates that the process is exiting.
SEXECED 0x00200000 Indicates that process has been run.
SEXECING 0x01000000 Indicates that the process is execing (performing an exec).
TKTHREAD 0x00001000 Indicates that the thread is a kernel only thread.
Note: You can see the definitions of all process and thread flags by referring to the p_flags and t_flags fields in the /usr/include/sys/proc.h and /usr/include/sys/thread.h files respectively.
S (-l)
The state of the process or kernel thread :
For processes:
O
Nonexistent
A
Active
W
Swapped
I
Idle
Z
Canceled
T
Stopped
For kernel threads:
O
Nonexistent
R
Running
S
Sleeping
W
Swapped
Z
Canceled
T
Stopped
UID (-f,- l)
The user ID number of the process (the login name is printed under the -f option).
PID (all)
The process ID of the process.
PPID (-f,-l)
The process ID of the parent process.
CLS (-c)
Scheduling class for the process. Printed only when the -c flag is used.
NI (-l)
The nice value of the process used in calculating priority for the sched_other policy.
PRI (-c, -l)
The priority of the process or kernel thread. Higher numbers mean lower priority.
ADDR (-l)
Contains the segment number of the process stack, if normal; if a kernel process, the address of the preprocess data area.
SZ (-l)
The size in pages of the core image of the process.
WCHAN(-l)
The event for which the process or kernel thread is waiting or sleeping. For a kernel thread, this field is blank if the kernel thread is running. For a process, the wait channel is defined as the wait channel of the sleeping kernel thread if only one kernel thread is sleeping; otherwise a star is displayed.
STIME (-f,-u)
The starting time of the process. The LANG environment variables control the appearance of this field.
TTY (all)
The controlling terminal for the process:
-
The process is not associated with a terminal.
?
Unknown
TIME (all)
The total runtime for the process. The time is displayed in the format of mm:ss or mmmm:ss if the runtime reaches 100 minutes, which is different from the displayed format if you use the -o time flag.
LTIME (-L)
The runtime for an individual LWP.
CMD (all)
Contains the command name. The full command name and its parameters are displayed with the -f flag.
LWP (-L)
The tid of the kernel thread.
NLWP(-Lf)
The number of kernel threads in the process.
PSR (-P)
The logical processor number of the processor to which the kernel thread is bound (if any). For a process, this field is shown if all its threads are bound to the same processor.
RSS (-ly)
The real memory (resident set) size of the process (in 1 KB units).

Format

The following list describes the field specifiers recognized by the system. These field specifiers can be used with the -o flag to specify the format for the output of the ps command.

The field specifiers recognized by the system are:
addr
Indicates the segment number of the process stack, if normal; if a kernel process, the address of the preprocess data area. The default header for this field is ADDR.
args
Indicates the full command name being executed. All command-line arguments are included, though truncation may occur. The default header for this field is COMMAND.
c
CPU utilization of process or thread, incremented each time the system clock ticks and the process or thread is found to be running. The value is decayed by the scheduler by dividing it by 2 once per second. For the sched_other policy, CPU utilization is used in determining process scheduling priority. Large values indicate a CPU intensive process and result in lower process priority whereas small values indicate an I/O intensive process and result in a more favorable priority. The default header for this field is C.
class
Indicates the scheduling policy for a kernel thread. The policies are sched_other, sched_fifo and sched_rr. The default header for this field is CLS.
comm
Indicates the short name of the command being executed. Command-line arguments are not included. The default header for this field is COMMAND.
etime
Indicates the elapsed time since the process started. The elapsed time is displayed in the format 
[[ dd -] hh: ]mm :ss
where dd specifies the number of days, hh specifies the number of hours, mm specifies the number of minutes, and ss specifies the number of seconds.

The default header for this field is ELAPSED.

f
Indicates flags (hexadecimal and additive) associated with the process. The default header for this field is COMMAND.
fname
Indicates the first 8 bytes of the base name of the process's executable file. The default header for this field is COMMAND.
gid
Indicates the effective group ID number of the process as a decimal integer. The default header for this field is GID. The login name is printed under the -f option.
group
Indicates the effective group ID of the process. The textual group ID is displayed. If the textual group ID cannot be obtained, a decimal representation is used. The default header for this field is GROUP.
lwp
Indicates the thread ID of the kernel thread. The default header for this field is TID.
nice
Indicates the decimal value of the process nice value. The default header for this field is NI.
nlwp
Indicates the number of kernel threads owned by the process. The default header for this field is THCNT.
pcpu
Indicates the ratio of CPU time used to CPU time available, expressed as a percentage. The default header for this field is %CPU.
pgid
Indicates the decimal value of the process group ID. The default header for this field is PGID.
pid
Indicates the decimal value of the process ID. The default header for this field is PID.
pmem
Indicates the percentage of real memory used by this process. The default header for this field is %MEM.
ppid
Indicates the decimal value of the parent process ID. The default header for this field is PPID.
pri
Indicates the priority of the process or kernel thread ; higher numbers mean lower priority. The default header for this field is PRI.
psr
Indicates the logical processor number of the processor to which the kernel thread is bound (if any). The default header for this field is PSR.
rgid
Indicates the real group ID number of the process as a decimal integer. The default header for this field is RGID.
rgroup
Indicates the real group ID of the process. The textual group ID is displayed. If the textual group ID cannot be obtained, a decimal representation is used. The default header for this field is RGROUP.
rss
Indicates the real memory (resident set) size of the process (in 1 KB units). The default header for this field is RSS.
ruid
Indicates the real user ID number of the process as a decimal integer. The default header for this field is RUID.
ruser
Indicates the real user ID of the process. The textual user ID is displayed. If the textual user ID cannot be obtained, a decimal representation is used. The default header for this field is RUSER.
s
Indicates the state of the process. The default header for this field is S.
sid
Indicates the process ID of the session leader. The default header for this field is SID.
stime
Indicates the starting time of the process. The LANG environment variables control the appearance of this field. The default header for this field is STIME.
time
Indicates the cumulative CPU time since the process started. The time is displayed in the same format as in etime. The default header for this field is TIME.
tty
Indicates the controlling terminal name of the process. The default header for this field is TT.
uid
Indicates the effective user ID number of the process as a decimal integer. The default header for this field is UID.
user
Indicates the effective user ID of the process. The textual user ID is displayed. If the textual user ID cannot be obtained, a decimal representation is used. The default header for this field is USER.
vsz
Indicates, as a decimal integer, the size in kilobytes of the core image of the process. The default header for this field is VSZ.
wchan
Indicates the event for which the process or kernel thread is waiting or sleeping. For a kernel thread, this field is blank if the kernel thread is running. For a process, the wait channel is defined as the wait channel of the sleeping kernel thread if only one kernel thread is sleeping; otherwise a star is displayed.

The default header for this field is WCHAN.

Flags (System V)

Some flags accept lists as arguments. Items in a list can be either separated by commas or else enclosed in double quotes and separated by commas or spaces. Values for proclist and pgrplist must be numeric.

Item Description
-a Writes to standard output information about all processes, except the session leaders and processes not associated with a terminal.
-A Writes to standard output information about all processes.
-c Prints information in a format that reflects scheduler properties. The -c flag affects the output of the -f and -l flags, as described below.
-d Writes to standard output information about all processes, except the session leaders.
-e Writes to standard output information about all processes, except kernel processes.
-f Generates a full listing.
-g pgrplist Writes to standard output information only about processes that are in the process groups specified by pgrplist. Values for pgrplist must be numeric.
-G grplist Writes to standard output information only about processes that are in the process groups specified by grplist. The -G flag accepts group names.
-j Displays session ID and process group ID.
-l Generates a long listing.
-L Prints status of active threads within a process.
-o format Displays information in the format specified by format. Multiple field specifiers can be specified for the format variable. The field specifiers that can be used with the -o flag are described above in the Format section.
-p proclist Displays information only about processes with the process numbers specified by proclist. Values for proclist must be numeric.
-P Displays the logical processor number of the processor to which the primary kernel thread of the process is bound (if any).
-s sidlist Displays all processes whose session leader's IDs are specified by sidlist.
-t termlist Displays information only about processes associated with the terminals specified by termlist.
-u uidlist Displays information only about processes with the user ID numbers or login names specified by uidlist.
-U uidlist Displays information only about processes with the user ID numbers or login names specified by uidlist.
-X Prints all available characters of each user and group name instead of truncating to the first 8 characters.
-y When combined with the -l option, changes the long listing so that it prints the "RSS'' and "SZ'' fields in kilobytes and does not print the "F'' and "ADDR'' fields.

Exit Status (System V)

This command returns the following exit values:

Item Description
0 Successful completion.
>0 An error occurred.

Security (System V)

Attention RBAC users and Trusted AIX users: This command can perform privileged operations. Only privileged users can run privileged operations. For more information about authorizations and privileges, see Privileged Command Database in Security. For a list of privileges and the authorizations associated with this command, see the lssecattr command or the getcmdattr subcommand.

Examples (System V)

  1. To display all processes, enter: 
    ps -e -f
  2. To list processes owned by the user 'guest', enter: 
    ps -f -l -u guest
  3. To list processes that are associated with the /dev/pts/0 and /dev/pts/1 terminals, enter: 
    ps -t pts/0,pts/1
  4. To list processes not associated with a terminal, enter: 
    ps -t -
  5. To display a specified format with field specifiers, enter: 
    ps -o ruser,pid,ppid,args
  6. To display information about all kernel threads in a process, enter: 
    ps -L
  7. To display session ID and process group IDs of all the processes, enter: 
    ps -jA
  8. To display the scheduling class and priority of processes, enter: 
    ps -c -l
  9. To display information about kernel threads and the number of kernel threads in a process, enter: 
    ps -L -f
  10. To display the processor to which the process or kernel thread is bound to, enter: 
    ps  -P
  11. To print an ASCII art for a given process (inetd in the example below), enter : 
    ps -T 14220
    Output will look like the following: 
         PID    TTY  TIME CMD
   14220      -  0:00 inetd
   16948      -  0:00    |\--telnetd
   32542  pts/4  0:00    |    \--ksh
   26504      -  0:00    |\--telnetd
   41272  pts/5  0:00    |    \--ksh
   26908  pts/5  0:00    |        \--vi
   28602      -  0:00    |\--telnetd
   24830  pts/0  0:00    |    \--ksh
  676416  pts/0  0:00    |        \--ksh
   29984      -  0:00    |\--telnetd
   38546  pts/6  0:00    |    \--ksh
   32126      -  0:00    |\--telnetd
   11162  pts/7  0:00    |    \--ksh
   34466      -  0:00    |\--rpc.ttdbserver
   35750      -  0:00    |\--telnetd
   23612  pts/3  0:00    |    \--ksh
   36294      -  0:00    |\--telnetd
   38096  pts/8  0:00    |    \--ksh
   39740      -  0:00    |\--telnetd
   42226  pts/9  0:01    |    \--ksh
   40632      -  0:00    |\--telnetd
   40232  pts/2  0:00    |    \--ksh
   32910  pts/2  0:00    |        \--dbx
  987990  pts/2  0:00    |            \--a.out
   40722      -  0:00    |\--telnetd
   16792 pts/10  0:00    |    \--ksh
   37886 pts/10  0:00    |        \--ps
  105716      -  0:00     \--telnetd
   29508  pts/1  0:00         \--ksh
   39478  pts/1  0:00             \--ksh
   38392  pts/1  0:00                 \--vi
  12. To print information about all processes rooted at a given pid, enter: 
    ps -fL 14220
    Output will look like the following: 
      UID   PID  PPID   C    STIME    TTY  TIME CMD
root 14220  8676   0   Apr 07      -  0:00 /usr/sbin/inetd
root 16948 14220   0   Apr 06      -  0:00 telnetd -a
root 23612 35750   0   Apr 10  pts/3  0:00 -ksh
root 24830 28602   1 18:30:56  pts/0  0:00 -ksh
root 28602 14220   0 18:30:55      -  0:00 telnetd -a
root 32542 16948   0   Apr 06  pts/4  0:00 -ksh
root 34466 14220   0   Apr 10      -  0:00 rpc.ttdbserver 100083 1
root 35750 14220   0   Apr 10      -  0:00 telnetd -a
root 40228 24830   8 18:36:01  pts/0  0:00 ps -fL 14220
  13. To display all processes with expanded user name, type: 
    ps -X -e -f
  14. To display the scheduling policies of a thread, enter the following command:
    #ps -m -o THREAD,sched
 USER     PID    PPID      TID ST  CP PRI SC WCHAN   F     TT BND COMMAND     SCH
suresana 1609830 4227284        - A   16  68  1   - 200001 pts/144   - ps -m  
                                                              -o THREAD sched 0
       -       -       -  6381739 R   16  68  1   -400000      -   - -        0
suresana 4227284 4239476        - A    1  60  1   -200801 pts/144   - bash    0
       -       -       -  4177981 S    1  60  1   -410400      -   - -        0
suresana 4239476  921694        - A    0  60  1   -240001 pts/144   - -ksh    0
       -       -       -  5554385 S    0  60  1   -10400      -   - -         0

Files (System V)

Item Description
/usr/sysv/bin/ps Contains the System V R4 ps command.
/etc/passwd Contains the user ID information.
/dev/pty* Indicates terminal (PTY) names.
/dev/tty* Indicates terminal (TTY) names.