Re: [Qemu-devel] [Xen-devel] Question about scsi emulation

[Stefano Stabellini]

On Mon, 23 Mar 2015, Stefan Hajnoczi wrote:
> On Wed, Mar 18, 2015 at 02:16:47PM -0700, Yaoli Zheng wrote:
> > We have problem using qemu emulated scsi driver(the old lsi). Wonder if any 
> > of other device model we can try for emulating scsi, and how we can get and 
> > config it in Xen? Having been told virtio-scsi is alternative one, but have 
> > no idea how to get it work in Xen.
> 
> The MegaSAS HBA might be another option.  Not sure whether MegaSAS or
> virtio-scsi are supported under Xen though.
 
Making MegaSAS HBA work on Xen should be easy.

Rather than virtio-scsi I would consider the new Xen pvscsi
frontend/backend drivers, now upstream in Linux
(drivers/scsi/xen-scsifront.c and drivers/xen/xen-scsiback.c). Usually
Xen PV drivers perform much better than virtio devices on Xen.

That said, probably most things would be better than the old lsi.