I was asking because in ovirt you may have had that option turned on, and in just regular libvirtd/kvm you didn't. It could be making a difference, but its really hard to tell. It's very strange that you're having write performance issues. This is one of the reasons I use oVirt. Performance has always been top notch compared to any other comprehensive solution I have tried.

Can you give this a try. Fire up a manager thats not hosted engine, maybe a vm on a laptop or something. And then add that centos install you already as a node in a datacenter that uses local storage. ... I have a feeling you might have had some NFS related issues with your write performance. If that is the case, then NFS tuning will be required to get what you are looking for.

To be honest this has never been a problem for me in any of my deployments, so if anyone else out there has something please feel free to chime in.

On Tue, Jul 28, 2015 at 8:19 PM, Alan Murrell <lists@murrell.ca> wrote:

On 28/07/15 03:06 PM, Donny Davis wrote:

Are you using virtio-scsi in oVirt?

Initially I thought I was, but realised it was just virtio (no '-scsi'), though I did have the guest tools installed (as well as having to install the virtio drivers to get the Win7 install to see the HDD). When I realised this, I added a second virtual HDD, making sure it was of type virtio-scsi and then I formatted it.

I ran the same tests from "Parkdale" on the second HDD, but unfortunately with the same results.

I am willing to install oVirt again and try another Win7 VM, making sure the first disk is virtio-scsi, if you think that may make a difference?

-Alan

Donny Davis