From mboxrd@z Thu Jan 1 00:00:00 1970 From: JR Subject: Re: Poor performance with virtio network driver on windows 2008 R2 on KVM Date: Thu, 15 May 2014 14:03:05 -0400 Message-ID: <53750159.2000404@gmail.com> References: <53738DB5.2050006@gmail.com> <5CC583AB71FC0C44A5CAB54823E83A84064D4D2E@SINPEX01CL01.citrite.net> <5CC583AB71FC0C44A5CAB54823E83A84064D5948@SINPEX01CL01.citrite.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: Venkateswara Rao Nandigam , "kvm@vger.kernel.org" Return-path: Received: from mail-ig0-f170.google.com ([209.85.213.170]:50474 "EHLO mail-ig0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752415AbaEOSDH (ORCPT ); Thu, 15 May 2014 14:03:07 -0400 Received: by mail-ig0-f170.google.com with SMTP id r10so688568igi.1 for ; Thu, 15 May 2014 11:03:06 -0700 (PDT) In-Reply-To: <5CC583AB71FC0C44A5CAB54823E83A84064D5948@SINPEX01CL01.citrite.net> Sender: kvm-owner@vger.kernel.org List-ID: Yes, thank you, Venkateswara, it is vhost=on is present. This is something specific to driver in windows since, in linux it performs very well. On 5/15/2014 1:41 PM, Venkateswara Rao Nandigam wrote: > One more important thing is to make sure you launch vhost thread for your virtio nic, as part of Guest instantiation. There will be a parameter "vhost=on" in Guest instantiation command line. > > -----Original Message----- > From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] On Behalf Of Venkateswara Rao Nandigam > Sent: Thursday, May 15, 2014 10:20 AM > To: JR; kvm@vger.kernel.org > Subject: RE: Poor performance with virtio network driver on windows 2008 R2 on KVM > > Try TSO offload on Guest Virtio interface > > And try passthrough interface mode at Host Level for this Guest Virtio Interface > > Thanks, > Venkatesh > > -----Original Message----- > From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] On Behalf Of JR > Sent: Wednesday, May 14, 2014 9:07 PM > To: kvm@vger.kernel.org > Subject: Poor performance with virtio network driver on windows 2008 R2 on KVM > > Greetings all, > > Though I don't believe that this is KVM problem per se, I'm seeing very poor network performance when using windows 2008R2 KVM instances with the virtio driver when on a 10G network. iperf results show linux VMs getting close to wire speeds, while windows only does about 1.3Gb/sec. > > I've tried a number of tcp settings (chimney, etc...) as recommended by some google searches but nothing has helped. > > Does anyone have any advice? > > Thanks much, > JR > > > -- > Your electronic communications are being monitored; strong encryption is an answer. My public key > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Your electronic communications are being monitored; strong encryption is an answer. My public key