From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH 0/9][RFC] KVM virtio_net performance
Date: Sun, 27 Jul 2008 16:48:58 +1000
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Cc: Mark McLoughlin <markmc@redhat.com>, kvm@vger.kernel.org,
	Herbert Xu <herbert@gondor.apana.org.au>
To: Avi Kivity <avi@qumranet.com>
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On Saturday 26 July 2008 19:45:36 Avi Kivity wrote:
> >   5) Eliminating an extra copy on the host->guest path only makes a
> >      barely measurable difference.
>
> That's expected on a host->guest test.  Zero copy is mostly important
> for guest->external, and with zerocopy already enabled in the guest
> (sendfile or nfs server workloads).

Note that this will also need the copyless tun patches.  If we're doing one 
copy from userspace->kernel anyway, this extra copy is probably lost in the 
noise.

Cheers,
Rusty.