When analysing the percentage utilisation in the OnApp Storage platform the value only increases.
Creating a file on the filesystem is reported in the filesystem and the VM.
Deleting a file on the filesystem however only shows a decreased value in the VM utilisation and not OnApp Storage.
This happens because the UI displays disk sparseness, not the actual filesystem utilisation. Once the VM writes data to storage, the blocks remain allocated even if the data is destroyed afterwards.
If a say 4GB file is created for the first time and uses unallocated space the utilisation will increase. Deleting this file will not show any decrease from the OnApp Storage platform.
If files were then once again created with a total size up to 4GB in the already allocated space, the VM will display the increased utilisation, while the UI will still show 27%.