sar (Unix)

`sar`
Stable release	sysstat 12.7.6 / July 3, 2024; 4 months ago
Repository	github.com/sysstat
Written in	C
Operating system	AIX, Linux, Solaris, HP-UX
Type	System reporting
Website	sysstat.github.io

‹The template Manual is being considered for merging.›

Called regularly by cron, sadc does the monitoring and stores its measurements to files in the /var/log/sa/ folder. The sar client can be used to explore this data.

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 /proc filesystem for gathering information.^[2]

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.^[3]

Most Linux distributions provide sar utility through the sysstat package.

Syntax

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

-f: filename Uses filename as the data source for sar. The default is the current daily data file /var/adm/sa/sadd.
-e: time Selects data up to time. The default is 18:00.
-i: 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,^[4] RedHat Enterprise Linux and SuSE provides additional reporting tools:

sar(1): Collect, report, or save system activity information. – Linux User Commands Manual
sa1(8): Collect and store binary data in the system activity daily data file. – Linux Administration and Privileged Commands Manual
sa2(8): shell variant of sar, supporting the same flags as sar command which write a daily report in the /var/log/sa directory. – Linux Administration and Privileged Commands Manual
sadf(1): , similar to sar but can write its data in different formats (CSV, XML, etc.). This is useful to load performance data into a database, or import them in a spreadsheet to make graphs.
iostat(1): reports basic CPU statistics and input/output statistics for devices, partitions and network filesystems. – Linux User Commands Manual
mpstat(1): reports individual or combined processor related statistics. – Linux User Commands Manual
pidstat(1): reports statistics for Linux tasks (processes) : I/O, CPU, memory, etc. – Linux User Commands Manual
nfsiostat(1): reports input/output statistics for network filesystems (NFS). – Linux User Commands Manual
cifsiostat(1): reports I/O statistics for CIFS resources. – Linux User Commands Manual

References

sar(1) – Solaris 11.4 User Commands Reference Manual
Easy system monitoring with SAR (IBM developerWorks)
System Activity Reporter (Softpanorama)
Article on sar at Computerhope

Footnotes

^ "Sysstat: Tags". GitHub.
^ "SYSSTAT". sebastien.godard.pagesperso-orange.fr.
^ "FreshPorts -- sysutils/bsdsar: System Activity Reporter for FreeBSD". www.freshports.org.
^ "Debian -- Details of package sysstat in sid". packages.debian.org.
^ "sag(1)" (PDF). SUNOS Reference Manual. Mountain View, California: Sun Microsystems. 1993-02-24. pp. 1–895. Retrieved 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.

[1] "Sysstat: Tags". GitHub.

[2] "SYSSTAT". sebastien.godard.pagesperso-orange.fr.

[3] "FreshPorts -- sysutils/bsdsar: System Activity Reporter for FreeBSD". www.freshports.org.

[4] "Debian -- Details of package sysstat in sid". packages.debian.org.

[5] "sag(1)" (PDF). SUNOS Reference Manual. Mountain View, California: Sun Microsystems. 1993-02-24. pp. 1–895. Retrieved 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.

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