Linux下PS命令详解

时间 2019-11-20

标签 linux 命令详解栏目 Linux 繁體版

原文原文链接

要对系统中进程进行监测控制，查看状态，内存，CPU的使用状况，使用命令：/bin/pslinux

（1） ps ：是显示瞬间进程的状态，并不动态连续；git

（2） top：若是想对进程运行时间监控，应该用 top 命令；shell

（3） kill 用于杀死进程或者给进程发送信号；express

（4） 查看文章最后的man手册，能够查看ps的每项输出的含义，to find: STANDARD FORMAT SPECIFIERSbash

===================================ps 的参数说明=============================session

l 长格式输出；app

u 按用户名和启动时间的顺序来显示进程；less

j 用任务格式来显示进程；ide

f 用树形格式来显示进程；svg

a 显示全部用户的全部进程（包括其它用户）；

x 显示无控制终端的进程；

r 显示运行中的进程；

ww 避免详细参数被截断；

-A 列出全部的进程
-w 显示加宽能够显示较多的资讯
-au 显示较详细的资讯
-aux 显示全部包含其余使用者的进程

-e 显示全部进程,环境变量
-f 全格式
-h 不显示标题
-l 长格式
-w 宽输出
a   显示终端上地全部进程,包括其余用户地进程
r   只显示正在运行地进程
x   显示没有控制终端地进程

咱们经常使用的选项是组合是 aux 或 lax，还有参数 f 的应用。
pids 只列出进程标识符,之间运用逗号分隔.该进程列表必须在命令行参数地最后一个选项后面紧接着给出,中间不能插入空格.好比：ps -f1,4,5 显示的是进程ID为1,4,5的进程

下介绍长命令行选项,这些选项都运用“--”开头：
--sort X[+|-] key [,[+|-] key [,…]] 从SORT KEYS段中选一个多字母键.“+”字符是可选地,由于默认地方向就是按数字升序或者词典顺序，“-”字符是逆序排序（即降序）.

好比： ps -jax -sort=uid,-ppid,+pid.
--help 显示帮助信息.
--version 显示该命令地版本信息.

在前面地选项说明中提到了排序键,接下来对排序键做进一步说明.须要注意地是排序中运用地值是ps运用地内部值,并不是仅用于某些输出格式地伪值.排序键列表见下表.

============排序键列表==========================
c cmd   可执行地简单名称
C cmdline   完整命令行
f flags   长模式标志
g pgrp   进程地组ID
G tpgid   控制tty进程组ID
j cutime   累计用户时间
J cstime   累计系统时间
k utime   用户时间
K stime   系统时间
m min_flt   次要页错误地数量
M maj_flt   重点页错误地数量
n cmin_flt 累计次要页错误
N cmaj_flt 累计重点页错误
o session   对话ID
p pid   进程ID
P ppid   父进程ID
r rss   驻留大小
R resident 驻留页
s size   内存大小(千字节)
S share   共享页地数量
t tty   tty次要设备号
T start_time 进程启动地时间
U uid   UID
u user   用户名
v vsize   总地虚拟内存数量(字节)
y priority 内核调度优先级
========================================ps aux 或 lax 输出的解释=========================

二、ps aux 或 lax 输出的解释

au(x) 输出格式 :
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND

USER: 进程全部者
PID: 进程ID

%CPU: 占用的 CPU 使用率
%MEM: 占用的内存使用率
VSZ: 占用的虚拟内存大小
RSS: 占用的内存大小

TTY: 终端的次要装置号码 (minor device number of tty)

STAT: 进程状态:

START: 启动进程的时间；
TIME: 进程消耗CPU的时间；
COMMAND:命令的名称和参数；

=========================================进程STAT状态==================================

D 没法中断的休眠状态（一般 IO 的进程）；
R 正在运行，在可中断队列中；
S 处于休眠状态，静止状态；
T 中止或被追踪，暂停执行；
W 进入内存交换（从内核2.6开始无效）；
X 死掉的进程；
Z 僵尸进程不存在但暂时没法消除；

W: 没有足够的记忆体分页可分配
WCHAN 正在等待的进程资源；

<: 高优先级进程
N: 低优先序进程
L: 有记忆体分页分配并锁在记忆体内 (即时系统或捱A I/O)，即,有些页被锁进内存

s 进程的领导者（在它之下有子进程）；
l 多进程的（使用 CLONE_THREAD, 相似 NPTL pthreads）；
+ 位于后台的进程组；

========================================kill 终止进程================================

kill 终止进程

有十几种控制进程的方法，下面是一些经常使用的方法:

kill -STOP [pid]
发送SIGSTOP (17,19,23)中止一个进程，而并不消灭这个进程。

kill -CONT [pid]
发送SIGCONT (19,18,25)从新开始一个中止的进程。

kill -KILL [pid]
发送SIGKILL (9)强迫进程当即中止，而且不实施清理操做。

kill -9 -1
终止你拥有的所有进程。

SIGKILL 和 SIGSTOP 信号不能被捕捉、封锁或者忽略，可是，其它的信号能够。因此这是你的终极武器。

==================================================范例==============================

$ ps
PID TTY TIME COMMAND
5800 ttyp0 00:00:00 bash
5835 ttyp0 00:00:00 ps
能够看到,显示地项目共分为四项,依次为PID(进程ID)、TTY(终端名称)、TIME(进程执行时间)、COMMAND(该进程地命令行输入).

能够运用u选项来查看进程全部者及其余少量详细信息,以下所示：
$ ps u
USER PID %CPU %MEM USZ RSS TTY STAT START TIME COMMAND
test 5800 0.0 0.4 1892 1040 ttyp0 S Nov27 0:00 -bash
test 5836 0.0 0.3 2528 856 ttyp0 R Nov27 0:00 ps u

在bash进程前面有条横线,意味着该进程即是用户地登陆shell,因此对于一个登陆用户来讲带短横线地进程只有一个.还能够看到%CPU、%MEM两个选项,前者指该进程占用地CPU时间

和总时间地百分比;后者指该进程占用地内存和总内存地百分比.
在这种状况下看到了全部控制终端地进程;固然对于其余那些没有控制终端地进程仍是没有观察到,因此这时就须要运用x选项.运用x选项能够观察到全部地进程状况.

1)ps a 显示现行终端机下的全部程序，包括其余用户的程序。
2)ps -A 显示全部程序。
3)ps c 列出程序时，显示每一个程序真正的指令名称，而不包含路径，参数或常驻服务的标示。
4)ps -e 此参数的效果和指定"A"参数相同。
5)ps e 列出程序时，显示每一个程序所使用的环境变量。
6)ps f 用ASCII字符显示树状结构，表达程序间的相互关系。
7)ps -H 显示树状结构，表示程序间的相互关系。
8)ps -N 显示全部的程序，除了执行ps指令终端机下的程序以外。
9)ps s 采用程序信号的格式显示程序情况。
10)ps S 列出程序时，包括已中断的子程序资料。
11)ps -t<终端机编号> 　指定终端机编号，并列出属于该终端机的程序的情况。
12)ps u 　以用户为主的格式来显示程序情况。
13)ps x 　显示全部程序，不以终端机来区分。

　最经常使用的方法是ps -aux,而后再用管道符号导向到grep去查找特定的进程,而后再对特定的进程进行操做。

==================================================

luther@gliethttp:~$ 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
luther@gliethttp:~$ man ps

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= SIMPLE PROCESS SELECTION -A Select all processes. Identical to -e. -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. -a Select all processes except both session leaders (see getsid(2)) and processes not associated with a terminal. 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. -d Select all processes except session leaders. -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. 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 -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). 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). -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. 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. -s sesslist Select by session ID. This selects the processes with a session ID specified in sesslist. 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. -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. --Group grplist Select by real group ID (RGID) or name. Identical to -G. --User userlist Select by real user ID (RUID) or name. Identical to -U. --group grplist Select by effective group ID (EGID) or name. This selects the processes whose effective group name or ID is in grouplist. The effective group ID describes the group whose file access permissions are used by the process (see geteuid(2)). The -g option is often an alternative to --group. --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. --sid sesslist Select by session ID. Identical to -s. --tty ttylist Select by terminal. Identical to -t and t. --user userlist Select by effective user ID (EUID) or name. Identical to -u and U. -123 Identical to --sid 123. 123 Identical to --pid 123. OUTPUT FORMAT CONTROL These options are used to choose the information displayed by ps. The output may differ by personality. -F extra full format. See the -f option, which -F implies. -O format is 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 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. -M Add a column of security data. Identical to Z. (for SE Linux) X Register format. Z Add a column of security data. Identical to -M. (for SE Linux) -c Show different scheduler information for the -l option. -f does 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. j BSD job control format. -j jobs format l display BSD long format. -l long format. The -y option is often useful with this. 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 -y Do not show flags; show rss in place of addr. This option can only be used with -l. --format format user-defined format. Identical to -o and o. --context Display security context format. (for SE Linux) OUTPUT MODIFIERS -H show process hierarchy (forest) N namelist Specify namelist file. Identical to -n, see -n above. 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. 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. 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. e Show the environment after the command. f ASCII-art process hierarchy (forest) 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. 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 -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) -w Wide output. Use this option twice for unlimited width. w Wide output. Use this option twice for unlimited width. --cols n set screen width --columns n set screen width --cumulative include some dead child process data (as a sum with the parent) --forest ASCII art process tree --headers repeat header lines, one per page of output --no-headers print no header line at all. --no-heading is an alias for this option. --lines n set screen height --rows n set screen height --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 --width n set screen width THREAD DISPLAY H Show threads as if they were processes -L Show threads, possibly with LWP and NLWP columns -T Show threads, possibly with SPID column m Show threads after processes -m Show threads after processes OTHER INFORMATION L List all format specifiers. -V Print the procps version. V Print the procps version. --help Print a help message. --info Print debugging info. --version Print the procps 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 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. 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 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 kB 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 COMMANDcommand 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 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 BLOCKEDmask 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 COMMANDcommand name (only the executable name). Modifications to the command name will not be shown. A process marked 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 COMMANDsee 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 ELAPSEDelapsed 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 COMMANDfirst 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 IGNOREDmask 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 STARTEDtime 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). 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 PENDINGmask 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 PENDINGsee pending. (alias pending, sig_pend). sigcatch CAUGHT see caught. (alias caught, sig_catch). sigignore IGNOREDsee ignored. (alias ignored, sig_ignore). sigmask BLOCKEDsee blocked. (alias blocked, sig_block). size SZ 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 STARTEDtime 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_timeSTART 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). 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 COMMANDsee 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. 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 S/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 top(1), pgrep(1), pstree(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. Linux July 28, 2004 PS(1)