vSphere 6.0 Storage Features Part 8: VAAI UNMAP changes

A few weeks, my good pal Cody Hosterman over at Pure Storage was experimenting with VAAI and discovered that he could successfully UNMAP blocks (reclaim) directly from a Guest OS in vSphere 6.0. VAAI are the vSphere APIs for Array Integration. Cody wrote about his findings here. Effectively, if you have deleted files within a Guest OS, and your VM is thinly provisioned, you can tell the array through this VAAI primitive that you are no longer using these blocks. This allows the array to reclaim them for other uses. I know a lot of you have been waiting for…

Thin Provisioning Considerations when formatting volumes in a Guest OS

I had this question recently regarding the best way to format volumes in a Windows 2008 Guest OS, and if there were any considerations with the different formatting types on a volume which resides on a thin provisioned VMDK. Just to be certain that what I was stating was actually true, I set up a small test. Bottom line – use quick format when formatting the volume as a normal format will fill the volume, negating the space-saving associated with thin provisioned volumes.