I have configured a host with pci passthrough for GPU pass through. Using this knowledge I went ahead and configured nvme SSD pci pass through. On the guest, I partitioned and mounted the SSD without any issues. 

Searching google for this exact setup I only see results about "local storage" where local storage = using a disk image on the hosts storage. So I have come here to try and find out if there are any concerns or gripes or issues with using nvme pci pass through compared to local storage. 

Some more detail about the setup: 

I have 2 identical hosts (nvidia gpu and also nvme pci SSD). A few weeks ago when I started researching converting one of these systems over (from native ubuntu) to ovirt using gpu pci pass through I found the information about local storage. I have 1 host (host #1) set up with local storage mode and the guest VM is using a disk image on this local storage.   

Host 2 has an identical hardware setup but I did not configure local storage for this host. Instead, I have the ovirt host OS installed on a SATA HDD and the nvme SSD is in pci pass through to a different guest instance. 

What I notice is Host 2 disk performance is approx. +30% increase over host #1 when running simple dd tests to write data to the disk. So at first glance it appears the nvme pci pass through gives better performance and this is desired, but I have not seen any ovirt documentation that explains that this is supported or any guidelines on configuring such a setup. 

Aside from the usual caveats when running pci pass through, are there any other gotchya's when running this type of setup (pci nvme ssd pass through)? I am trying to discover any unknowns about this before I use this for real data. I have no previous experience with this and this is my main reason for emailing the group. 

Any insight appreciated. 

Kind regards,