vmfs6 and reclamation

[baber]

Dear all

Hi

i read about vmfs6 and meet new feature space reclamation now i want to know :

1- will be work this mode just when we use vms with thin provisioning disk ?

2-is that means for example when i create a vm with 200GB disk and 50Gb of that is unused this space will be get from vm and will be add to datastore automatically ?

BR

[daphnissov]

The answer to both is "Yes" however you need to understand there are some caveats. This only works with guest operating systems that support issuing the UNMAP command and not all of them do. Windows 2012 R2 and higher support this as well as some versions of Linux. You also need to make sure you're using a fully-patched version of ESXi 6.5 since there was a bug that was fixed related to this. Lastly, the space is only reclaimed if the UNMAPs are issued on 1 MB boundaries. Read these articles from Cody Hosterman for a fuller understanding of how this works.

Direct Guest OS UNMAP in vSphere 6.0 | Cody Hosterman

In-Guest UNMAP Fix in ESXi 6.5 Part I: Windows | Cody Hosterman

https://blog.purestorage.com/in-guest-unmap-fix-in-esxi-6-5-part-i-windows/

Space Reclamation Requests from Guest Operating Systems