Sar: Difference between revisions
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== Command and options == | == Command and options == | ||
sar has a lot of arguments and options and basic comman syntax is following, | sar has a lot of arguments and options and basic comman syntax is following, | ||
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$sar --help | $sar --help | ||
Full description is available in sar man page<ref>https://linux.die.net/man/1/sar</ref> | Full description is available in sar man page<ref>https://linux.die.net/man/1/sar</ref> | ||
Here are few examples, geeksforgeeks site has more examples to use sar<ref>https://www.geeksforgeeks.org/sar-command-linux-monitor-system-performance/</ref> | |||
Here are few examples, | |||
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Revision as of 12:19, 7 December 2023
Monitoring server resources is a crucial part of identifying any bottlenecks and possible issues on your server.
sar stands for “System Activity Reporter” and provides a wide range of metrics related to system usage, including CPU utilization, memory usage, disk I/O, network activity.
on Ubuntu, sar can be installed by following[1]
#install sar
$ sudo apt-get install -y sysstat
# Enable data collecting
sed -i 's/false/true/g' /etc/default/sysstat
# Change the collection interval from every 10 minutes to every 2 minutes
sed -i 's/5-55\/10/*\/2/g' /etc/cron.d/sysstat
# Restart service
$ sudo systemctl start sysstat
sar system service
sar can be run as system service as well,
- sudo systemctl start sysstat
- sudo systemctl enable sysstat
- This will add the required cron jobs so that the system data is collected accordingly. The cron jobs will be added at cat /etc/cron.d/sysstat
Command and options
sar has a lot of arguments and options and basic comman syntax is following,
$ sar -[ options ] time_interval number_of_tines_to_display
$sar --help
Full description is available in sar man page[2]
Here are few examples, geeksforgeeks site has more examples to use sar[3]
| Options | Description | output format |
|---|---|---|
sar -u 2 30
|
-u for all CPU,
|
12:14:32 PM CPU %user %nice %system %iowait %steal %idle
12:14:34 PM all 0.00 0.00 0.03 0.00 0.00 99.97
12:14:36 PM all 0.00 0.00 0.03 0.00 0.00 99.97
12:14:38 PM all 0.00 0.00 0.00 0.02 0.00 99.98
|
sar -r 2 30
|
-r for memory | 12:15:15 PM kbmemfree kbavail kbmemused %memused kbbuffers kbcached kbcommit %commit kbactive kbinact kbdirty
12:15:17 PM 51770940 128790180 934688 0.71 18792 76432800 1471616 1.10 12511540 64247964 20
12:15:19 PM 51770940 128790180 934688 0.71 18792 76432800 1471616 1.10 12511540 64247964 20
12:15:21 PM 51771048 128790296 934472 0.71 18800 76432800 1471616 1.10 12511544 64247964 48
|
| sar -n DEV 4 | -n for network interfaces,
4 means that the sar command should run every 2 seconds |
12:17:06 PM IFACE rxpck/s txpck/s rxkB/s txkB/s rxcmp/s txcmp/s rxmcst/s %ifutil
12:17:08 PM eno2np1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
12:17:08 PM eno1np0 19.50 15.50 2.42 1.43 0.00 0.00 1.00 0.00
12:17:08 PM docker0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
12:17:08 PM enxb03af2b6059f 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
12:17:08 PM lo 5.00 5.00 0.39 0.39 0.00 0.00 0.00 0.00
|
| sar -d | -d command to view block device, disk I/O statistics, including IOPS | 12:00:01 PM DEV tps rkB/s wkB/s dkB/s areq-sz aqu-sz await %util
12:02:01 PM dev259-0 1.74 0.10 9.10 0.00 5.28 0.00 3.36 0.31
12:02:01 PM dev8-0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
12:02:01 PM dev8-16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
12:02:01 PM dev8-32 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
|