Is there any way of getting volume space back to the array once you have deleted data on the volume at the OS level?
Newer versions of Windows (i.e., 2012 and 2008 R2, I believe) support SCSI UNMAP. Space reclamation can be triggered by file deletion, a file system level trim, or a storage optimization operation. File system level trim is enabled for a storage device designed to perform “read return zero” after a trim or an unmap operation. Nimble also supports this, and space is actually freed up on the array when garbage collection takes place.
For additional info, here is a pretty good read: Thin Provisioning (Windows Drivers)
Is this for Windows, Linux, or ESX?
Search the forum for 'reclaim space' for info and scripts you can run to return space to the array on win 2003/2008. Be great if nimble could include a background process with NCM that does what win 2012 does. Until then will need to run separate scripts or util. ..
Retrieving data ...