how to see the size of /var
$ sudo du -h --max-depth=1 /var | sort -h | tail -n 10
[sudo] password for mark:
4.0K /var/local
4.0K /var/opt
1.4M /var/mail
1.9M /var/spool
12M /var/tmp
16M /var/backups
20M /var/log
1020M /var/cache
14.7G /var/lib
15.7G /var