ubuntu@domU-12-31-39-06-2D-A6:/var/log/postgresql$ sudo du -h / | grep ^[0-9.]*G
1.1G    /usr
1.4G    /var/lib/postgresql/9.1/main/base/11919
1.5G    /var/lib/postgresql/9.1/main/base
1.6G    /var/lib/postgresql/9.1/main
1.6G    /var/lib/postgresql/9.1
1.6G    /var/lib/postgresql
1.7G    /var/lib
2.1G    /var
du: cannot access `/proc/14465/task/14465/fd/4': No such file or directory
du: cannot access `/proc/14465/task/14465/fdinfo/4': No such file or directory
du: cannot access `/proc/14465/fd/4': No such file or directory
du: cannot access `/proc/14465/fdinfo/4': No such file or directory
3.3G    /


ubuntu@domU-12-31-39-06-2D-A6:/var/log/postgresql$ sudo df -H
Filesystem      Size  Used Avail Use% Mounted on
/dev/xvda1      8.5G  8.0G   56M 100% /
udev            300M   13k  300M   1% /dev
tmpfs           124M  218k  124M   1% /run
none            5.3M     0  5.3M   0% /run/lock
none            310M     0  310M   0% /run/shm
none            105M     0  105M   0% /run/user