Reclaim free space on Windows 2008 R2?

[Paul Hutchings]

Can anyone confirm whether free space is automatically reclaimed when thin provisioning volumes on Windows 2008 R2 with SANiQ 9.0 please?

I have some thin volumes assigned directly to the iSCSI initiator of a 2008 R2 box and despite no snapshots having taken place, the CMC is showing slightly less capacity in use now than it was earlier.

I don't see how that's possible without some sort of "reclaim" process?

Thanks,
Paul

[Ben Drawbaugh]

It does not get reclaimed automatically. The problem is that Windows doesn't actually delete files, it just marks the blocks as deleted. Theoretically it should be possible to use something like sdelete to clear the blocks and then shrink the volume, but the only way I know for a fact works is to create a new volume, copy the files over to it and then change the drive letter. This obviously won't work on a C drive, but should on any data drive.

If it is VMWare, then you can use storage vmotion to copy the vmdk to another SAN volume and choose to make it thin before copying -- assuming you run sdelete beforehand.