Linux performance testing tools: iostat, ps, and pstree

Linux Performance Testing Tool iostat is part of the sysstat package. Iostat displays the average CPU time after the system is started, similar to uptime), and displays the usage of the disk subsystem. iostat is used to monitor CPU utilization and disk utilization.

Linux Performance Testing Tool iostat


% User: user-level application) CPU usage
% Nice: CPU usage of the user level with nice priority added
% Sys: system level kernel) CPU usage
% Idle: idle CPU resources
Device: block Device name
Tps: the number of I/O requests transmitted by the device per second ). Multiple independent I/O requests can be combined into one transmission operation because one transmission operation can have different capacities.

Blk_read/s, Blk_wrtn/s: The number of blocks read and written by the device per second. The block size may be different.
Blk_read and Blk_wrtn: Total number of Block devices read and written since the system was started.

Linux performance testing tools ps and pstree


Ps and pstree commands are the most common basic commands for system analysis. ps commands provide a list of running processes. The number of processes listed depends on the parameters attached to the command. For example, the ps-A command lists all processes and their corresponding process IDPID), the process PID is required before using other tools, such as pmap or renice.

On the system running the java application, the output of the ps-A command is easily beyond the display range of the screen, which makes it difficult to obtain complete information about all processes. In this case, the pstree command can be used to display all process information in a tree structure and integrate sub-process information. The Pstree command is very useful for analyzing the source of the process.