Sysstat

Sysstat is a very basic and light, but extremely powerful metrics system for Unix.

Install

Can be installed on most distributions.

sudo apt install sysstat 
sudo pacman -S sysstat

Enable Collection

Statistics collection is not enabled by default on some distros, typically Debian & Ubuntu derivitaves.

Edit /etc/default/sysstat

ENABLED="true"

The service can be enabled and restarted.

sudo systemctl enable sysstat
sudo systemctl restart sysstat

Stats Collection

On most distros, a cron job will be automatically created - On others it must be created manually.

Cron-style

/etc/cron.d/sysstat

*/2 * * * *   root  /usr/lib/sysstat/sa1 1  1
59 23 * * *   root  /usr/lib/sysstat/sa1 60 2

Or if full stats collection is required:

*/2 * * * *   root  /usr/lib/sysstat/sa1 1  1 -S ALL
59 23 * * *   root  /usr/lib/sysstat/sa1 60 2 -A ALL

This job will log the statistics at a given time and save the output to /var/log/saxx

Systemd Timer

The timer lives in /lib/systemd/system/sysstat-collect.timer. It is possible to edit the timer to lower the sample interval:

[Unit]
Description=Run system activity accounting tool every 10 minutes

[Timer]
OnCalendar=*:00/2

[Install]
WantedBy=sysstat.service

Then, the service unit file can be optionally modified to collect power state:

[Unit]
Description=system activity accounting tool
Documentation=man:sa1(8)
After=sysstat.service

[Service]
Type=oneshot
User=root
ExecStart=/usr/lib/sa/sa1 1 1 -S ALL

Then, systemd can be reloaded and enabled.

sudo systemctl daemon-reload

sudo systemctl enable sysstat-collect.timer
sudo systemctl start  sysstat-collect.timer

Statistics

As an admin, stats can be read from sysstat with the sar command.

sar

To see all stats from today:

sar -A

To see stats form yesterday:

sar -1

sadf can also be used to create graphics:

sadf -g > output.svg

Stats Types

CPU stats:

sar -p

Memory stats:

sar -r

IO stats:

sar -b

Network stats:

sar -n DEV

Socket stats:

sar -n SOCK

Load stats:

sar -q LOAD
sar -q PSI

Graphs

Since the sadf command takes sar args, you can make neat graphs with multiple stat types in one. Example:

1. Graph system load and IO activity:

   sadf -g -- -q LOAD -b > output.svg
   

2. Graph memory and swap:

   sadf -g -- -r -W > output.svg
   

3. Temp/Fan for laptop

   sadf -g -- -m ALL > output.svg
   

4. Block device IO (disk usage)

   sadf -g -- -d > output.svg
   

Additional Graphics options

Additional opts can be specified in the sadf command:

1. Show all metrics, one type per row:

   sadf -g -O packed -- -A > output.svg
   

2. Show 24 hours of metrics starting from midnight:

   sadf -g -O oneday -T > output.svg