Technical Tip: Disk usage showing 0 GB

[jstan]

Description
This article describes the disk usage calculation from GUI.

Solution

# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root               378.3M    59.1M     319.2M  16% /
/dev/vda1               100.0M     71.7M     28.3M  72% /data
/dev/vdb2                57.9G    637.3M     54.4G   1% /var

Disk usage monitor only shows values in Gigabyte.
If the disk usage is smaller than <1GB, it always shows 0.