Sar (Unix)
# Sar (Unix)

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.

## 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.

Most Linux distributions provide sar utility through the sysstat package.

## Syntax

### -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.

## Sysstat package

Additional to sar command, Linux sysstat package in Debian, 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
