Linux Commands 12

Properties of the process

Process ID (PID): is the only numeric value used to differentiate processes

Parent process ID of the parent process (PPID)

The user ID (UID) of the initiating process and the group to which it belongs (GID)

Process state: State divided into run R, hibernate s, zombie Z

Priority of Process Execution

The name of the terminal to which the process is connected

Process resource consumption: For example, resource size (memory, CPU usage)

The management of Linux processes is implemented through process management tools, such as PS, kill, etc.

PS Top Management process

PS gives us a one-time view of the process, it provides a view of the results is not dynamic continuous, if you want to monitor the process, you should use the top tool.

PS Monitoring Process tool static Current state

PS, the parameter description

L Long Format output

U show process in order of user name and start time

F to display the process in a tree-shaped format

A shows all processes for all users (including other users)

R shows the running process

E shows all processes, including those that do not control the terminal

X shows no control of the terminal process

The common option combination is Ps-aux

[Email protected] ~]# Ps-aux
USER PID%cpu%MEM VSZ RSS TTY STAT START time COMMAND
Root 1 0.1 0.3 192104 7352? Ss 21:45 0:03/usr/lib/systemd/systemd--swi
Root 2 0.0 0.0 0 0? S 21:45 0:00 [Kthreadd]
Root 3 0.0 0.0 0 0? S 21:45 0:00 [ksoftirqd/0]

Explanation of PS aux output

Owner of the USER process;

The ID of the PID process;

PPID parent process;

Percentage of CPU consumed by the%CPU process;

%MEM% of memory occupied;

The nice value of the NI process;

The VSZ process consumes virtual memory size;

RSS fixed amount of memory used;

The terminal ID of the TTY process startup;

TSAT process status;

R is in operation;

S is in a dormant state;

T stop or be traced;

Z Zombie process;

N low-priority processes;

L Some pages are locked in memory;

Leader of the S-process (under it there are sub-processes);

Start START process time;

The time the process consumes the CPU;

The parameter of the command name;

Top Dynamic View Process

Linux Commands 12