High disk I/O

Check high disk I/O commands:

1. iotop -oPa -d 2: High I/O on /var partition
2. glances: High iowait and load
3. iostat -2: /var high I/O confirmation
4. ls -lhS /var/log/*log | head: Large mail.log
5. tail -f /var/log/mail.log: Rapid, continuous logging