Tag Archives: In-guest

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

What’s new in ESXi 6.5 Storage Part IV: In-Guest UNMAP CBT Support

This is the fourth in my series of what’s new in ESXi 6.5 storage. Here are the previous posts:

What’s new in ESXi 6.5 Storage Part I: UNMAP

What’s new in ESXi 6.5 Storage Part II: Resignaturing

What’s new in ESXi 6.5 Storage Part III: Thin hot extend

Here is another post for vSphere 6.5 UNMAP! So many improvements and this is a big one for many users. Certainly makes me happy. Previously, in vSphere 6.0.x, when in-guest space reclamation was introduced, the enabling of change block tracking for a given virtual disk blocked the guest OS from being able to issue UNMAP to that disk and┬átherefore prevented it from leveraging the goodness it provides. Rumor has it that this undesirable behavior continued in vSphere 6.5…

leecorso

Continue reading What’s new in ESXi 6.5 Storage Part IV: In-Guest UNMAP CBT Support