====== vmstat ======
# update every second, size in mb
vmstat 1 -S m
====== iostat ======
# update every 5 seconds, extended, size in mb
iostat -t 5 -x -m
====== sysstat ======
Sysstat is a daemon that collects statistics in a regular interval.
===== installing =====
Before it can be used it needs to be installed installed with
sudo apt-get install sysstat
sudo vi /etc/default/sysstat # set ENABLED="true"
the stats collection is triggered every 10 minutes by cron (/etc/cron.d/sysstat)
===== using =====
Once stats have been collected, they can be viewed using the **sar** command
# show cpu usage
sar
# show memory usage
sar -r
# show disk usage
sar -dp