From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: virtio-net zero-copy Date: Mon, 18 May 2009 17:00:14 +0300 Message-ID: <4A1169EE.3050603@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, kvm@vger.kernel.org To: Raju Srivastava Return-path: Received: from mx2.redhat.com ([66.187.237.31]:37303 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751798AbZEROAQ (ORCPT ); Mon, 18 May 2009 10:00:16 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Raju Srivastava wrote: > Greetings, > > Could someone let me know if current virtio-net supports zero-copy? I > see some discussion here: > http://thread.gmane.org/gmane.comp.emulators.kvm.devel/28061/ > (copyless virtio net thoughts) and it looks like the copyless > virtio-net is not supported by KVM yet. That is correct. > If this is true, then is there > any plan to add the zero copy to the virtio-net? > Yes, but it will be a difficult journey. > I use KVM in 10G network environment and found the CPU usage is > saturated when network traffic becomes heavy. The native Linux under > the same load only consumes less than 10% CPU. > Running the latest guest and host software (both qemu and kernel) will improve things somewhat. -- error compiling committee.c: too many arguments to function