Getting Started with Linux-processes, scheduled tasks

W

Load average:0.12, 0.09, 0.02 1, 5, 15 min. loading condition, 0.8 below normal

JCPU CPU time for the corresponding user execution command

PCPU the CPU time consumed by the current command

What the corresponding user is executing the command

Idle time corresponding to the user idle

Ps

Many parameters, you can first use PS--help to view the parameters.

Ps-aux,ps-le detailed information for all user processes

Time process starts dependent on total CPU consumption

%CPU takes up the total CPU time of the score ratio

%MEM occupies the total memory of the score ratio

More inclined and mated piping ps-aux in practical use | grep httpd, Ps-le | grep 3306

Ps-uu user to view user-initiated processes

Kill

Kill PID

Kill-9 PID Strong off

KILL-1 pid Restart

Killall httpd

Pgrep, Pkill

Pgrep mysqld List all process numbers for mysqld

Pkill Mysqld closed according to service name

Nice, Renice

Nice-n cmd Specifies the program's run priority

Renice-n PID changes the running process priority (-N:-20--19,-20 max)

Nohup

Nohup Find/-name init* >/root/f.txt & user Exit Login command to continue execution

Suspend, resume

CTRL + Z hang up

FG, GB restore to foreground, background continue execution

Jobs view the pending process

Top

D Specify the Refresh time

u know the user's process

K Terminating a process

？ See more help information

Scheduled Tasks

/ETC/RC.D/INIT.D/ATD Start Service

At a time of execution

At time (hh:mm mm/dd/yyyy)

>at command (using absolute path)

>at command

>ctrl + D Save

Working with files

At-f at.txt hh:mm mm/dd/yyyy

At < At.txt hh:mm mm/dd/yyyy

View At-l, delete at-d serial number

/etc/at. [Allow|deny] Configures which users can use the at

Crontab{l:list|r:rm|e:edit} repeating tasks

Minutes Hours Day Month Week command/script

0 18 * 1-3 2,5 January to March, every Tuesday and Friday, six o'clock in the afternoon execution

*/2 * * * * * run every 2 minutes