Linux command ps use

The ps command in Linux is an abbreviation of Process Status. The ps command is used to list those processes running in the system.

Note: ps is to display the status of the instantaneous process, not dynamic and continuous. If you want to monitor the process in real time, you should use the top command.

1. Parameter introduction

• -e, -A: all processes are displayed

• -f: display the output in full format

• -a: display all processes under the current terminal, including processes of other users

• -u: user-based process status 

• -x: usually used with the a parameter to list more complete information

• -aux to filter processes according to CPU or memory usage, for example ps -aux --sort -pcpuorps -aux --sort -pmem

• -l: display a long list

• -L: Display the threads in the process, for example ps -L 123, 123 is the process ID

• -j: display task information

• -H: Display progress in a hierarchy, tree structure

• -o: allows the user to specify which columns will be displayed when the ps command is run

2. The result column information table of the ps command indicates:

• UID: the user who started the process

• PID: ID of the starting process

• PPID: the parent process ID of the startup process

• C,% CPU: the percentage of CPU resources used by the process

• S, STAT: the status of the process

• TTY: which terminal is running on

• TIME: CPU time used by the process

• CMD: Process command

• PRI: the priority of the process

• ADDR: memory address of the process

• START: The time when the process was triggered to start

• COMMAND: the actual command of the program

• % MEM: the percentage of physical memory occupied by the process

• VSZ: The amount of virtual memory used by the process (Kbytes)

• RSS: The fixed amount of memory occupied by the process (Kbytes)

• SZ: used memory size