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What is the role of process management in Linux system? This problem may be often seen in our daily study or work. I hope you can gain a lot from this question. The following is the reference content that the editor brings to you, let's take a look at it!

1. What is a process?

A process is a program or command that is being executed, each process is a running entity, has its own address space, and takes up some system resources.

2. Process management role?

Determine the health status of the server

Production depends on all the processes in the system

Kill process

= = View process command =

Ps

The command line result indicates

Top

Top command results

The first line of information is the task information queue

Load avaerage:0.00 0.000.00 respectively represents the average load of the system in the previous 1 minute, 5 minutes and 15 minutes. If it is a single core, it is generally considered that when the load is less than 1, the load is smaller, and when it is greater than 1, the load is larger.

Second behavior CPU information

% Cpu (s):

0.1us: percentage of CPU occupied by user mode

0.1sy: percentage of CPU occupied by system mode

0.1ni: percentage of CPU occupied by user processes that have changed priority

1.1id: percentage of CPU of idle CPU

0.1wa: percentage of CPU occupied by processes waiting for input / output

0.1hi: percentage of CPU occupied by hard interrupt request service

0.1si: percentage of CPU occupied by soft interrupt request service

0.1st: percentage of virtual time, that is, virtual CPU waits when a virtual machine is available

Percentage of time of actual CPU

Third behavior physical memory information

Fourth behavior Exchange Partition (swap) information

Pstree

Check the process tree, that is, to see the relationship between the process trees, that is, which process is the parent process and which is the child process, you can clearly see who created whom.

= = terminate the process = =

Kill

= = work management =

Jobs-l

Displays the ID working in the background

The + sign represents the most recent work put in the background, which is also the work that is restored by default when the work is restored.

The-sign represents the last but one job to be put backstage.

Ctr+Z representative puts the work in the background paused state.

& means to put the work in the background to run

The execution command restored in the background cannot interact with the foreground, otherwise it cannot be restored to the background.

= = system resource view = =

Free to view memory usage status

The difference between caching and buffering?

Cache is used to speed up data reading from the hard disk, and buffer is used to speed up data writing to the hard disk.

= = system timing tasks =

Crond Service Management and access Control

Crond is usually started by default

Service crond restartchkconfig crond on

Crontab settings for crontab users

* php / mnt/d/CODE/MY/EighthWorld/artisan schedule:run > > / home/fantasy/error.log 2 > & 1 first *: minute 0-59 second *: hour 0-23 third *: day of the month 1-31 fourth *: month 1-12 fifth *: day of the week 0-7 (0 and 7 represent Sundays)

Thank you for reading! After reading the above, do you have a general understanding of the role of process management in the Linux system? I hope the content of the article will be helpful to all of you. If you want to know more about the relevant articles, you are welcome to follow the industry information channel.

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