[libvirt] [PATCH] qemu: Support multiple queue virtio-scsi

[Paolo Bonzini]

----- Messaggio originale -----
> Da: "Eric Blake" <eblake at redhat.com>
> A: "Osier Yang" <jyang at redhat.com>
> Cc: libvir-list at redhat.com, pbonzini at redhat.com
> Inviato: Lunedì, 1 aprile 2013 18:43:11
> Oggetto: Re: [libvirt] [PATCH] qemu: Support multiple queue virtio-scsi
> 
> On 04/01/2013 10:31 AM, Osier Yang wrote:
> > No, multiple queue is not enabled by default. For "what happens if it
> > doesn't match the number of vcpus", honestly, I'm not sure about it,
> > my understanding is it doesn't have to match. But matching will have
> > the best performance, and with this thought I think an attribute allows
> > the user to specify the number makes sense instead of a boolean
> > attribute.  @paolo, can you confirm or deny this?
> 
> Then maybe all we need is just a recommendation that matching the number
> of vcpus tends to give best performance, but not stating that it is
> mandatory to match.

I think in the current patches anything that doesn't exactly matches
the number of VCPUs will fallback to single-queue.  But it doesn't have
to be the case, so a numeric attribute is preferrable.

Paolo