vSphere VAAI Performance on the HP P4000 G2

With the recent release of SAN/iQ 9.0 which supports the VAAI vStorage offload features of vSphere 4.1, I thought I would run a quick block zeroing test to see the difference.

The setup was as follows:

4 x HP P4500 G2 nodes in a cluster (48 x 15K SAS disks)
500GB Network RAID-10 (2-Way mirror) volume
VMFS Datastore at 8MB blocksize

From the CLI of the ESXi host, I created a zeroed out VMDK file 50GB in size:

vmkfstools -c 50G -d eagerzeroedthick P4000vaai-test.vmdk

This was run once with VAAI enabled on the ESXi host and once with VAAI disabled (via the advanced Datamover options)


The results are pretty conclusive. For block zeroing on a VMDK, VAAI accelerates the operation by 4-5x

VAAI enabled: 109 seconds
VAAI disabled: 482 seconds

7 thoughts on “vSphere VAAI Performance on the HP P4000 G2

  1. So now that HP is finally supporting VAAI, where woudl I get the client for the Lefthand devices to utilize this feature?

  2. Great post. Saw your recent twitter about Veeam performance as well. Would you confirm your config, especially with the iscsi initiator (sw or hw).

    1. Config of the Veeam backup server as a VM? or iSCSI setup on the ESX. I was looking at doing a post on the Veeam config in the next two weeks

      1. iscsi setup on ESX (and in VM) – nothing too detailed, just want to check I’m interpreting your config correctly re sw or hw iscsi initiator. I had the impression you were using software iscsi initiator (MSFT), but then you mentioned leveraging CBT, and I thought this was mutually exclusive.
        Will look forward to your post.

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