Linux Command set

1. Top Command

Top-D 1-p pid [, PID...] // set it to delay 1 s. The default value is delay 3 s.

To sort by memory usage, Shift + M (sort by memory usage)

2. pmap command
Pmap PID

3. ps command
PS aux | grep process_name

4. view the status file in the/proc/process_id/folder.

View memory usage of a single program
1. view the program status using top-P PID
2. PS-Aux | grep process_name
3. CAT/proc/Pid/status
The details of the current process are printed. The memory is vmrss.

Delete a folder (cannot be rolled back) Rm-RF

Modify the own of a file

Chown-r root. group file name

PS: chown-r root. Root/usr/local/xxx

Get root permission

Sudo Su-

Date, month, day, year, second
Date-s allows you to directly set the system time
 
For example, the command to set the system time to June 10, 1996 is as follows.
# Data-s 06/10/96
The command to set the system time to 01:12:00 P.M. is as follows.
# Date-s 13:12:00

Transmission between Linux

SCP/usr/local/APP (local path) root@192.168.20.99:/usr/local/usersadf

Extract

Unzip xxxx

Tar zxvf xxxx

Jar-xvf project. War

Package

Tar cvzf/usr/bak/hot-_00000000.tar.gz/usr/hot/

SSH password-free login-configure the trust relationship between the two servers A to B as an example of the sub-source machine:
Run the following command under the root user:
Ssh-keygen-T rsamv/root/. Ssh/id_rsa.pub/root/. Ssh/authorized_keys
Put the/root/. Ssh/authorized_keys file of the source machine to the directory of the target machine:/root/. Ssh/(create the. Ssh directory)
Run ssh-lroot-P22 IP address on the source machine
Enter Yes, And the password-free login is displayed.

In Linux, SSH connections are not automatically disconnected.

VI/etc/profile

Add tmout = 300 (unit: seconds)

Source/etc/profile

Complete

Search for strings in VIM

In command mode, enter/word, which is the word "word" in the search file. Is it from the top of the file to the bottom? Word: Search for the word "word" in the file, from the top of the file to the surface

How to find a file location in Linux

Locate xxxx