Beginner's Guide: Linux top commands

From: http:// OS .51cto.com/art/201108/285581.htm

Linux top commands

TOP Command is one of the most popular performance monitoring tools, which we must understand. It is an excellent interactive tool for monitoring performance. It provides overall system performance, but reporting process information is the top command's strength. The top command interaction interface is as follows:

The top page consists of two parts: the top part of the cursor displays information about the overall system performance, and the bottom part of the cursor displays information about each process. The cursor is used to enter the Operation Command.

Linux TOP command INTERFACE

The content displayed in the first line is the same as that in the uptime command. [l] can display and hide this area:

Top: this is meaningless. It's just a name and

01:47:56: current system time

Up: How long has the system been started?

2 users: the current 2 users are online

Load average: 0.00, 0.00, 0.00: CPU load information of the system for 1 minute, 5 minutes, and 15 minutes

Row 2:

Task.

38 Total: it is easy to understand that there are 38 tasks, that is, 38 processes.

1 running: 1 process is running

37 sleeping: 37 processes sleep

0 stopped: Number of stopped Processes

0 zombie: Number of zombie Processes

CPU (s): displays the overall CPU information for this row

0.0% us: the CPU usage percentage of user-mode processes, excluding the CPU usage time of tasks with a negative renice value.

0.7% Sy: CPU usage percentage

0.0% Ni: Percentage of CPU time of a user-state process with a negative renice value. Nice indicates priority.

99.3% ID: Percentage of idle CPU time

0.0% Wa: Percentage of CPU time waiting for I/O

0.0% Hi: Percentage of CPU hard interrupt time

0.0% Si: Percentage of CPU soft interrupt time

0.0% ST: I don't know

Row 3:

Men: Memory

256412 k total: total physical memory

30156 K used: the amount of physical memory used

226256 free: The amount of idle physical memory

8176 K buffers: The amount of physical memory used as the kernel Cache

Swap: swap space

337356 k total: Total number of swap Areas

0 k used: the number of swap areas used

337356 K free: Number of idle swap Areas

12160 K cached: Total number of buffer swap Areas

Row 4:

PID: process ID

User: process owner

PR: process priority. The smaller the value, the higher the execution priority.

Ninice: Value

Virt: Virtual Memory occupied by processes

Res: physical memory occupied by the Process

SHR: shared memory used by the Process

S: the status of the process. S indicates sleep, r indicates running, Z indicates frozen, and N indicates that the priority of the process is negative.

% CPU: CPU usage of processes

% Mem: Percentage of physical memory and total memory used by the Process

Time +: The total CPU time occupied by the process after it is started, that is, the accumulated value of the CPU usage time.

Command: Process startup command name

Linux top commands

Below I will list some common Linux TOP command operation commands:

Q: exit the TOP command.

<Space>: refresh now

S: Set the Refresh Interval

C: Display command full Mode

T: displays or hides the process and CPU status information.

M: displays or hides memory status information.

L: displays or hides the uptime information.

F: add or remove process display flag

S: In the accumulative mode, the CPU time occupied by completed or exited sub-processes is accumulated to the mite + of the parent process.

P: Ranking by % CPU usage

T: Ranking by mite +

M: ranked by % mem

U: displays user processes.

R: Modify the renice value of a process.

Kkill: Process

I: only running processes are displayed.

W: Save the top settings to the file ~ /. Toprc. The setting of the toprc file will be automatically called at the next startup.

H: HELP command.

Original article: http://www.itwhy.org/2011/07-05/437.html