Space Efficient Sparse (SESparse)can now reclaim spaces from the linked clone pools and provides efficient usage of available disk space. The feature requires vSphere 5.1 as well as Hardware version 9. This feature only works with OS base disk.
The space reclamation process is kicked off automatically by View when the reclaimable space is above the threshold.
Since this process can be I/O-intensive, It’s a good plan to use the blackout periods appropriately to avoid affecting user experience.