Re: [PATCH v1] vhost: avoid large order allocations

Michael Mueller
2014-05-14T08:11:15Z

On Tue, 13 May 2014 18:15:27 +0300
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Tue, May 13, 2014 at 04:29:58PM +0200, Romain Francoise wrote:
> > "Michael S. Tsirkin" <mst@redhat.com> writes:
> >
> > > Please dont' do this, extra indirection hurts performance.
> > > Instead, please change vhost_net_open and scsi to allocate the whole
> > > structure with vmalloc if kmalloc fails, along the lines of
> > > 74d332c13b2148ae934ea94dac1745ae92efe8e5
> >
> > Back in January 2013, you didn't seem to think it was a good idea:
> >
> > https://lkml.org/lkml/2013/1/23/492
>
> Hmm true, and Dave thought the structure's too large.
> I'll have to do some benchmarks to see what the effect
> of Michael's patch is, performance-wise.
> If it's too expensive I can pick up your patch, no need to
> repost.
>

Thanks, let us know then.