There (http://docplayer.net/9304188-Exploiting-the-latest-kvm-features-for-optimized-virtualized-enterprise-storage-performance.html) was a comparison:

Full virtualization – IDE, SATA, SCSI
–Good guest compatibility
–Bad performance (many trap-and-emulate operations), does not scale beyond 1 thread ← Not recommended for enterprise storage

Para-virtualization – virtio-blk, virtio-scsi
– Efficient guest ↔ host communication through virtio ring buffer (virtqueue)
– Good performance
– Virtualization benefits (e.g. device sharing among guests, etc.)

How to enable Virtio-blk-data-plane:

<domain type='kvm' ....>
...
<qemu:commandline>
<qemu:arg value='-set'/>
<qemu:arg value='device.virtio-disk0.x-data-plane=on'/>
</qemu:commandline>
<domain>
(source: http://docplayer.net/9304188-Exploiting-the-latest-kvm-features-for-optimized-virtualized-enterprise-storage-performance.html ; page 16)

What is your suggestion / experience regarding this?