Linux command: PS pstree top Process Management

PS Introduction to Commands:

This command is used to view a user process.

1 . Command format:

ps [option]: PS parameter

Common use format: PS aux |grep ' keyword ' to find related process information by keyword

[[Email protected] ~]# PS aux display information for all processes

USER PID%cpu%MEM VSZ RSS TTY STAT START time COMMAND

Root 1 0.0 0.0 2900 1436? Ss 21:04 0:02/sbin/init

Root 2 0.0 0.0 0 0? S 21:04 0:00 [Kthreadd]

Root 3 0.0 0.0 0 0? S 21:04 0:00 [migration/0]

Root 4 0.0 0.0 0 0? S 21:04 0:00 [ksoftirqd/0]

Root 5 0.0 0.0 0 0? S 21:04 0:00 [migration/0]

Parse displays the meaning of the message: (the process in brackets above is the kernel process)

User: Username PID: Process number%cpu: Percentage of CPU consumed by process%MEM: Percentage of process memory

VSZ: Virtual memory consumption size RSS: Actual memory footprint TTY: Terminal mode

STAT: Process state start: Process start time: Process runtime command: Commands to start a process

2 . Command function:

View user processes.

Process Status Classification:

D: Non-disruptive sleep status

R: Run or Ready state

S: An interruptible sleep state

T: Stop state

Z: Zombie State

Process Type classification: (processes with brackets are kernel processes)

<: high-priority process

N: Low-priority process

+: Processes in the foreground process group

L: Multithreaded Process

S: The first process of session connection process    

3 . Command parameter: PS No parameter shows foreground process only by default

A: Displays all terminal-related processes (that is, processes that start with the user's login)

U: Show the process is initiated by that user

X: Displays all terminal-independent processes (that is, processes that are started when the user is not logged on after the system starts)

Common formats

-e: Show All Processes

-L: Show processes in long format

-F: More detailed display of process information than L

-O: Specifies that a field in the process is displayed

Pstree: Process tree view process tree can be viewed by keyword pstree |grep "keyword"

Pgrep: The process number of the process is displayed in grep only Usage:pgrep bash shows the process number about the bash process

[[email protected] ~]# pgrep-u root bash View Bash-related processes running as root user

2036

Pidof: Displays only the process number (PID) of processes, which can be found by process name Usage:pidof sshd
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4 . Command instance:

This article is from the "Learn Linux history" blog, please be sure to keep this source http://woyaoxuelinux.blog.51cto.com/5663865/1879035

Linux command: PS pstree top Process Management