Sar (Unix) Explained

sar
Latest Release Version:	sysstat 12.1.1^[1]
Latest Preview Version:	sysstat 11.7.4
Latest Preview Date:	^[2]
Programming Language:	C

System Activity Report ('''sar''') is a Unix System V-derived system monitor command used to report on various system loads, including CPU activity, memory/paging, interrupts, device load, network and swap space utilization. Sar uses /[[procfs|proc]] filesystem for gathering information.^[3]

Platform support

Sar was originally developed for the Unix System V operating system; it is available in AIX, HP-UX, Solaris and other System V based operating systems but it is not available for macOS or FreeBSD. Prior to 2013 there was a bsdsar tool, but it is now deprecated.^[4]

Most Linux distributions provide sar utility through the sysstat package.

Syntax

sar [-flags] [-e time ] [-f filename ] [-i sec ] [-s time ]

: 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

[user@localhost]$ sar # Displays current CPU activity.

Sysstat package

Additional to sar command, Linux sysstat package in Debian,^[5] RedHat Enterprise Linux and SuSE provides additional reporting tools:

See also

• atopsar
• Nmon
• [[sag (Unix)|sag]] - "system activity graph" command^[6]
• ksar- BSD licensed Java-based application to create graph of all parameters from the data collected by Unix sar utilities.
• CURT, IBM AIX CPU Usage Reporting Tool
• isag, tcl based command to plot sar/sysstat data

References

• • Easy system monitoring with SAR (IBM developerWorks)
• System Activity Reporter (Softpanorama)
• Article on sar at Computerhope

Notes and References

1. Web site: Release v12.1.1: Sysstat-12.1.1 · sysstat/Sysstat. GitHub.
2. Web site: SYSSTAT. sebastien.godard.pagesperso-orange.fr.
3. Web site: SYSSTAT. sebastien.godard.pagesperso-orange.fr.
4. Web site: FreshPorts -- sysutils/bsdsar: System Activity Reporter for FreeBSD. www.freshports.org.
5. Web site: Debian -- Details of package sysstat in sid. packages.debian.org.
6. Web site: sag(1). 1993-02-24. SUNOS Reference Manual. Sun Microsystems. Mountain View, California. 1–895. 2010-05-04. sag - system activity graph [...] DESCRIPTION sag graphically displays the system activity data stored in a binary data file by a previous sar(1) run..