System Activity Report (sar) is a

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system monitor A system monitor is a Computer hardware, hardware or software component used to monitor system resources and performance in a computer system. Among the management issues regarding use of system monitoring tools are resource usage and privacy. ...

command used to report on various system loads, including CPU activity, memory/paging, interrupts, device load, network and

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utilization. Sar uses

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filesystem for gathering information.

Platform support

Sar was originally developed for Solaris operating system and it is available in Linux, Solaris, AIX, HP-UX, but it is not available for macOS or FreeBSD. Prior to 2013 there was a bsdsar tool, but it is now deprecated.

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

distributions, such as Debian, Red Hat Enterprise Linux, SuSe and Ubuntu provide sar utility through the sysstat package.

Syntax

sar

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; : filename Uses filename as the data source for sar. The default is the current daily data file /var/adm/sa/sadd. ; : time Selects data up to time. The default is 18:00. ; : sec Selects data at intervals as close as possible to sec seconds.

Example

ser@localhost sar # Displays current CPU activity.

Sysstat package

Additional to sar command, Linux

sysstat sysstat (''system statistics'') is a collection of performance monitoring tools for Linux. It is available on Unix and Unix-like operating systems. Software included in sysstat package: * sar Collect, report, or save system activity informat ...

package in Debian, RedHat Enterprise Linux and SuSE provides additional reporting tools: * * * * * * * * *

References

*
Easy system monitoring with SAR (IBM developerWorks)System Activity Reporter (Softpanorama)

Footnotes