From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: updated: kvm networking todo wiki
Date: Thu, 30 May 2013 16:48:29 +0930
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: kvm <kvm@vger.kernel.org>, "Michael S. Tsirkin" <mst@redhat.com>, netdev@vger.kernel.org, qemu-devel <qemu-devel@nongnu.org>, Linux Virtualization <virtualization@lists.linux-foundation.org>, herbert@gondor.hengli.com.au, Anthony Liguori <anthony@codemonkey.ws>
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Stefan Hajnoczi <stefanha@gmail.com> writes:
> On Thu, May 30, 2013 at 7:23 AM, Rusty Russell <rusty@rustcorp.com.au> wrote:
>> On the receive side, what can we do better than readv?  If we need to
>> return to userspace to tell the guest that we've got a new packet, we
>> don't win on latency.  We might reduce syscall overhead with a
>> multi-dimensional readv to read multiple packets at once?
>
> Sounds like recvmmsg(2).

Wow... the future is here, today!

Thanks,
Rusty.

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From: Rusty Russell <rusty@rustcorp.com.au>
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Date: Thu, 30 May 2013 16:48:29 +0930
Message-ID: <87fvx5kkai.fsf@rustcorp.com.au>
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Subject: Re: [Qemu-devel] updated: kvm networking todo wiki
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: kvm <kvm@vger.kernel.org>, "Michael S. Tsirkin" <mst@redhat.com>, netdev@vger.kernel.org, Jason Wang <jasowang@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, Linux Virtualization <virtualization@lists.linux-foundation.org>, herbert@gondor.hengli.com.au, Anthony Liguori <anthony@codemonkey.ws>, Dmitry Fleytman <dmitry@daynix.com>

Stefan Hajnoczi <stefanha@gmail.com> writes:
> On Thu, May 30, 2013 at 7:23 AM, Rusty Russell <rusty@rustcorp.com.au> wrote:
>> On the receive side, what can we do better than readv?  If we need to
>> return to userspace to tell the guest that we've got a new packet, we
>> don't win on latency.  We might reduce syscall overhead with a
>> multi-dimensional readv to read multiple packets at once?
>
> Sounds like recvmmsg(2).

Wow... the future is here, today!

Thanks,
Rusty.