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

As you might’ve seen, Cormac Hogan just posted about an UNMAP fix that was just released. This is a fix I have been eagerly awaiting for some time, so I am very happy to see it released. And thankfully it does not disappoint.

First off, some official information:

Release notes:

https://kb.vmware.com/kb/2148989

Manual patch download:

https://my.vmware.com/group/vmware/patch#search

Or you can run esxcli if you ESXi host has internet access to download and install automatically:

esxcli software profile update -p ESXi-6.5.0-20170304001-standard -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml

Continue reading “In-Guest UNMAP Fix in ESXi 6.5 Part I: Windows”

Allocation Unit Size and Automatic Windows In-Guest UNMAP on VMware

I posted shortly after ESXi 6.0 came out a while back explaining how to do in-guest UNMAP with Windows. See the original post here:

Direct Guest OS UNMAP in vSphere 6.0

The high-level workflow if you don’t want to read the post is:

  1. You delete a file in Windows
  2. Run Disk Optimizer to reclaim the space
  3. Windows issues UNMAP to the filesystem
  4. ESXi shrinks the virtual disk
  5. If EnableBlockDelete is enabled on the ESXi hosts, ESXi will issue UNMAP to reclaim the space on the array

This had a few requirements:

  • ESXi 6.0+
  • VM hardware version 11+
  • Thin virtual disk
  • CBT cannot be enabled (though this restriction is removed in ESXi 6.5 see this post)

Continue reading “Allocation Unit Size and Automatic Windows In-Guest UNMAP on VMware”