The following table describes the commands for managing system processes.
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The ps command enables you to check the status of active processes on a system, and also display technical information about the processes. This data is useful for administrative tasks, such as determining how to set process priorities.
Depending on which options you use, the ps command reports the following information:
Current status of the process
Process ID
Parent process ID
User ID
Scheduling class
Priority
Address of the process
Memory used
CPU time used
The following list describes some fields that are reported by the ps command. The fields that are displayed depend on which option you choose. For a description of all available options, see the ps (1) man page.
The process ID.
The parent process ID.
The processor utilization for scheduling. This field is not displayed when the –c option is used.
The scheduling class to which the process belongs such as real-time, system, or timesharing. This field is included only with the –c option.
The kernel thread's scheduling priority. Higher numbers indicate a higher priority.
The process's nice number, which contributes to its scheduling priority. Making a process “nicer” means lowering its priority.
The address of the proc structure.
The virtual address size of the process.
The address of an event or lock for which the process is sleeping.
The starting time of the process in hours, minutes, and seconds.
The terminal from which the process, or its parent, was started. A question mark indicates that there is no controlling terminal.
The total amount of CPU time used by the process since it began.
The command that generated the process.
You can display detailed information about the processes that are listed in the /proc directory by using process commands. The following table lists the /proc process commands. The /proc directory is also known as the process file system (PROCFS). Images of active processes are stored in the PROCFS by their process ID number.
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For more information, see the proc (1) man page.
The process tools are similar to some options of the ps command, except that the output that is provided by these commands is more detailed.
The process commands do the following:
Display more information about processes, such as fstat and fcntl, working directories, and trees of parent and child processes
Provide control over processes by allowing users to stop or resume them
You can display detailed technical information about processes or control active processes by using some of the process commands. Table 2–2 lists some of the /proc commands.
If a process becomes trapped in an endless loop, or if the process takes too long to execute, you might want to stop (kill) the process. For more information about stopping processes using the kill or the pkill command, see Chapter 2, Managing System Processes.
The /proc file system is a directory hierarchy that contains additional subdirectories for state information and control functions.
The /proc file system also provides an xwatchpoint facility that is used to remap read-and-write permissions on the individual pages of a process's address space. This facility has no restrictions and is MT-safe.
Debugging tools have been modified to use the xwatchpoint facility, which means that the entire xwatchpoint process is faster.
The following restrictions no longer apply when you set xwatchpoints by using the dbx debugging tool:
Setting xwatchpoints on local variables on the stack due to SPARC based system register windows.
Setting xwatchpoints on multithreaded processes.
For more information, see the proc (4) and mdb (1) man pages.
$ ps [-efc]
Displays only the processes that are associated with your login session.
Displays full information about all the processes that are being executed on the system.
Displays process scheduler information.
The following example shows output from the ps command when no options are used.
$ ps PID TTY TIME COMD 1664 pts/4 0:06 csh 2081 pts/4 0:00 ps
The following example shows output from the ps –ef command. This output shows that the first process that is executed when the system boots is sched (the swapper) followed by the init process, pageout, and so on.
$ ps -ef
UID PID PPID C STIME TTY TIME CMD
root 0 0 0 18:04:04 ? 0:15 sched
root 5 0 0 18:04:03 ? 0:05 zpool-rpool
root 1 0 0 18:04:05 ? 0:00 /sbin/init
root 2 0 0 18:04:05 ? 0:00 pageout
root 3 0 0 18:04:05 ? 2:52 fsflush
root 6 0 0 18:04:05 ? 0:02 vmtasks
daemon 739 1 0 19:03:58 ? 0:00 /usr/lib/nfs/nfs4cbd
root 9 1 0 18:04:06 ? 0:14 /lib/svc/bin/svc.startd
root 11 1 0 18:04:06 ? 0:45 /lib/svc/bin/svc.configd
daemon 559 1 0 18:04:49 ? 0:00 /usr/sbin/rpcbind
netcfg 47 1 0 18:04:19 ? 0:01 /lib/inet/netcfgd
dladm 44 1 0 18:04:17 ? 0:00 /sbin/dlmgmtd
netadm 51 1 0 18:04:22 ? 0:01 /lib/inet/ipmgmtd
root 372 338 0 18:04:43 ? 0:00 /usr/lib/hal/hald-addon-cpufreq
root 67 1 0 18:04:30 ? 0:02 /lib/inet/in.mpathd
root 141 1 0 18:04:38 ? 0:00 /usr/lib/pfexecd
netadm 89 1 0 18:04:31 ? 0:03 /lib/inet/nwamd
root 602 1 0 18:04:50 ? 0:02 /usr/lib/inet/inetd start
root 131 1 0 18:04:35 ? 0:01 /sbin/dhcpagent
daemon 119 1 0 18:04:33 ? 0:00 /lib/crypto/kcfd
root 333 1 0 18:04:41 ? 0:07 /usr/lib/hal/hald --daemon=yes
root 370 338 0 18:04:43 ? 0:00 /usr/lib/hal/hald-addon-network-discovery
root 159 1 0 18:04:39 ? 0:00 /usr/lib/sysevent/syseventd
root 236 1 0 18:04:40 ? 0:00 /usr/lib/ldoms/drd
root 535 1 0 18:04:46 ? 0:09 /usr/sbin/nscd
root 305 1 0 18:04:40 ? 0:00 /usr/lib/zones/zonestatd
root 326 1 0 18:04:41 ? 0:03 /usr/lib/devfsadm/devfsadmd
root 314 1 0 18:04:40 ? 0:00 /usr/lib/dbus-daemon --system
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# pgrep process
The process ID is displayed in the first column of the output.
# /usr/bin/pcommand PID
The process command that you want to run. Table 2–2 lists and describes these commands.
Identifies the process ID.
The following example shows how to use process commands to display more information about a cron process.
# pgrep cron Obtains the process ID for the cron process
4780
# pwdx 4780 Displays the current working directory for the cron process
4780: /var/spool/cron/atjobs
# ptree 4780 Displays the process tree that contains the cron process
4780 /usr/sbin/cron
# pfiles 4780 Displays fstat and fcntl information
4780: /usr/sbin/cron
Current rlimit: 256 file descriptors
0: S_IFCHR mode:0666 dev:290,0 ino:6815752 uid:0 gid:3 rdev:13,2
O_RDONLY|O_LARGEFILE
/devices/pseudo/mm@0:null
1: S_IFREG mode:0600 dev:32,128 ino:42054 uid:0 gid:0 size:9771
O_WRONLY|O_APPEND|O_CREAT|O_LARGEFILE
/var/cron/log
2: S_IFREG mode:0600 dev:32,128 ino:42054 uid:0 gid:0 size:9771
O_WRONLY|O_APPEND|O_CREAT|O_LARGEFILE
/var/cron/log
3: S_IFIFO mode:0600 dev:32,128 ino:42049 uid:0 gid:0 size:0
O_RDWR|O_LARGEFILE
/etc/cron.d/FIFO
4: S_IFIFO mode:0000 dev:293,0 ino:4630 uid:0 gid:0 size:0
O_RDWR|O_NONBLOCK
5: S_IFIFO mode:0000 dev:293,0 ino:4630 uid:0 gid:0 size:0
O_RDWR
# pgrep process
The process ID displayed in the first column of the output.
# /usr/bin/pcommand PID
The process command that you want to run. Table 2–2 lists and describes these commands.
Identifies the process ID.
# ps -ef | grep PID
You might need to stop (kill) a process that is in an endless loop, or stop a large job before it is completed. You can kill any process that you own. The system administrator can kill any process in the system except for those processes with process IDs of 0, 1, 2, 3, and 4. Killing these processes most likely will crash the system.
For more information, see the pgrep (1) , pkill (1) , and kill (1) man pages.
$ pgrep process
For example:
$ pgrep netscape 587 566
The process ID is displayed in the output.
To list all user processes:
# ps -fu user
To locate a specific process owned by a user:
# ps -fu user | grep process
$ pkill [signal] PID
When no signal is included in the pkill command-line syntax, the default signal that is used is –15 (SIGKILL). Using the –9 signal (SIGTERM) with the pkill command ensures that the process terminates promptly. However, the –9 signal should not be used to kill certain processes such as a database process or an LDAP server process because data might be lost.
The name of the process to stop.
$ pgrep process
The process you terminated should no longer be listed in the output of the pgrep command.
# ps -fu user
where user is the owner of the process.
The process ID is displayed in the first column of the output.
# kill [signal-number] PID
When no signal is included in the kill command-line syntax, the default signal that is used is –15 (SIGKILL). Using the –9 signal (SIGTERM) with the kill command ensures that the process terminates promptly. However, the –9 signal should not be used to kill certain processes such as a database process or an LDAP server process because data might be lost.
Is the process ID of the process that you want to terminate.
$ ps
The process you terminated should no longer be listed in the output of the ps command.
The pargs command and the preap command improve process debugging. The pargs command prints the arguments and environment variables that are associated with a live process or core file. The preap command removes defunct (zombie) processes. A zombie process has not yet had its exit status claimed by its parent. These processes are generally harmless but can consume system resources if they are numerous. You can use the pargs and preap commands to examine any process that you have the privileges to examine. When you become an administrator, you can examine any process.
For information about using the preap command, see the preap (1) man page. For information about the using the pargs command, see the pargs (1) man page. See also the proc (1) man page.
Example 2-3 Debugging a Process (pargs)The pargs command solves a long-standing problem of being unable to display with the ps command all the arguments that are passed to a process. The following example shows how to use the pargs command in combination with the pgrep command to display all the arguments that are passed to a process.
# pargs `pgrep ttymon` 579: /usr/lib/saf/ttymon -g -h -p system-name console login: -T sun -d /dev/console -l argv[0]: /usr/lib/saf/ttymon argv[1]: -g argv[2]: -h argv[3]: -p argv[4]: system-name console login: argv[5]: -T argv[6]: sun argv[7]: -d argv[8]: /dev/console argv[9]: -l argv[10]: console argv[11]: -m argv[12]: ldterm,ttcompat 548: /usr/lib/saf/ttymon argv[0]: /usr/lib/saf/ttymon
The following example shows how to use the pargs –e command to display the environment variables that are associated with a process.
$ pargs -e 6763 6763: tcsh envp[0]: DISPLAY=:0.0