From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mohr Subject: Re: Networking latency - what to =?UTF-8?Q?expect=3F?= Date: Thu, 29 Nov 2012 08:50:41 -0700 Message-ID: References: <65e3a10030795eacd577b0fac1a10bb1@de.mcbf.net> <87lidkjwho.fsf@os.inf.tu-dresden.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit To: Return-path: Received: from seeker.mcbf.net ([109.239.49.157]:57162 "EHLO seeker.mcbf.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751165Ab2K2Puo (ORCPT ); Thu, 29 Nov 2012 10:50:44 -0500 Received: from localhost ([127.0.0.1] helo=de.mcbf.net) by seeker.mcbf.net with esmtp (Exim 4.72) (envelope-from ) id 1Te6Nu-000576-15 for kvm@vger.kernel.org; Thu, 29 Nov 2012 16:50:42 +0100 In-Reply-To: <87lidkjwho.fsf@os.inf.tu-dresden.de> Sender: kvm-owner@vger.kernel.org List-ID: On 2012-11-29 07:48, Julian Stecklina wrote: > Thus spake David Mohr : > >> * vm->vm (same host) 22k > > This number is in the same ballpark as what I am seeing on pretty > much > the same hardware. > > AFAICS, there is little you can do to the current virtio->virtio code > path that would make this substantially faster. Thanks for the feedback. Considering that it's better than the hardware network performance my main issue is actually the latency of communication between VMs on different hosts: * vm->vm (diff. hosts) 7k It is obvious that there is a lot more going on compared to same host communication, but only ~30% of the performance when the network hardware should not be slowing it down (too) much? Thanks, ~David