De Linuxmemo.
simple top-like I/O monitor
iotop -o
iotop -oPa -d 2: High I/O on /var partition
glances: High iowait and load
iostat -2: /var high I/O confirmation
ls -lhS /var/log/*log | head: Large mail.log
tail -f /var/log/mail.log: Rapid, continuous logging