Re: [PATCH v2 06/10] nvme/core: add mdev interfaces

From: Maxim Levitsky
Date: Mon May 06 2019 - 04:35:11 EST


On Mon, 2019-05-06 at 11:31 +0300, Maxim Levitsky wrote:
> On Sat, 2019-05-04 at 08:49 +0200, Christoph Hellwig wrote:
> > On Fri, May 03, 2019 at 10:00:54PM +0300, Max Gurtovoy wrote:
> > > Don't see a big difference of taking NVMe queue and namespace/partition
> > > to
> > > guest OS or to P2P since IO is issued by external entity and pooled
> > > outside
> > > the pci driver.
> >
> > We are not going to the queue aside either way.. That is where the
> > last patch in this series is already working to, and which would be
> > the sensible vhost model to start with.
>
> Why are you saying that? I actualy prefer to use a sepearate queue per
> software
> nvme controller, tat because of lower overhead (about half than going through
> the block layer) and it better at QoS as the separate queue (or even few
> queues
> if needed) will give the guest a mostly guaranteed slice of the bandwidth of
> the
> device.

Sorry for typos - I need more coffee :-)

Best regards,
Maxim Levitsky