This video shows PerfectStorage running a reclaim operation in an ESX-hosted Windows Server 2008 Guest in order to shrink a thin-provisioned VMDK.
In the Windows guest, data is copied to the drive causing the thin-provisioned VMDK file to expand. Using the datastore browser we can see the provisioned size is 10.486 GB and the actual size is 9.631 GB.
Data is then deleted from the drive. Looking at the drive properties, from the Windows point of view, there is no data on the drive. NTFS shows the drive is empty but when the data is deleted Windows doesn’t communicate this information to the ESX host and the VMDK remains fully provisioned.
The PerfectStorage client analyzes the drive and finds 9.02 GB of recoverable space. We start a reclaim operation by clicking the Start button. The VMDK shrinks on the fly without needing to take the guest out of production.
After PerfectStorage has completed the reclaim operation we can see the VMDK has been shrunk down to about 515 MB, recovering space in the datastore.
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