本文转自（https://blog.csdn.net/qq_31391261/article/details/79419740）
OS:centos6.5
操作步骤：
1）输入sar命令：sar --help
结果：提示command not found
原因：未安装工具使用yum命令安装， yum install sysstat
说明：（yum也是个工具，如果你的linux系统无yum工具需要自行安装）
安装过程，如下：
yum install sysstat过程记录
[root@besttest ~]# yum install sysstat
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.tuna.tsinghua.edu.cn
* updates: mirrors.aliyun.com
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package sysstat.i686 0:9.0.4-33el6_9.1 will be installed
--> Finished Dependency Resolution
[root@besttest ~]# yum install sysstat
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.tuna.tsinghua.edu.cn
* updates: mirrors.aliyun.com
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package sysstat.i686 0:9.0.4-33el6_9.1 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
===============================================================================================================================================================================================================================
Package Arch Version Repository Size
===============================================================================================================================================================================================================================
Installing:
sysstat i686 9.0.4-33el6_9.1 updates 228 k
Transaction Summary
===============================================================================================================================================================================================================================
Install 1 Package(s)
Total download size: 228 k
Installed size: 804 k
Is this ok [y/N]: y
Downloading Packages:
sysstat-9.0.4-33el6_9.1.i686.rpm | 228 kB 00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Warning: RPMDB altered outside of yum.
** Found 5 pre-existing rpmdb problem(s), 'yum check' output follows:
LoadGenerator-11.00.000-1.i386 has missing requires of libicudata.so
LoadGenerator-11.00.000-1.i386 has missing requires of libicudata.so.36
LoadGenerator-11.00.000-1.i386 has missing requires of libicui18n.so.36
LoadGenerator-11.00.000-1.i386 has missing requires of libicutu.so.36
LoadGenerator-11.00.000-1.i386 has missing requires of libicuuc.so.36
Installing : sysstat-9.0.4-33el6_9.1.i686 1/1
Verifying : sysstat-9.0.4-33el6_9.1.i686 1/1
Installed:
sysstat.i686 0:9.0.4-33el6_9.1
Complete!
2）安装完成sysstat工具，即可使用sar命令：
