From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH] vhost: Add polling mode Date: Tue, 29 Jul 2014 12:44:36 +0200 Message-ID: <20140729104436.GB13388@redhat.com> References: <20140729080640.GA10185@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: abel.gordon@gmail.com, Alex Glikson , Eran Raichstein , Joel Nider , kvm@vger.kernel.org, Yossi Kuperman1 To: Razya Ladelsky Return-path: Received: from mx1.redhat.com ([209.132.183.28]:1526 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752908AbaG2Ko0 (ORCPT ); Tue, 29 Jul 2014 06:44:26 -0400 Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Tue, Jul 29, 2014 at 01:30:03PM +0300, Razya Ladelsky wrote: [..] had to snip off the quoted text, it's mangled up to unreadability. Please take a look at Documentation/email-clients.txt to fix this. > > This is an optimization patch, isn't it? > > Could you please include some numbers showing its > > effect? > > > > > > Hi Michael, > Sure. I included them in a reply to Jason Wang in this thread, > Here it is: > http://www.spinics.net/linux/lists/kvm/msg106049.html > Hmm there aren't a lot of numbers there :(. Speed increased by 33% but by how much? E.g. maybe you are getting from 1Mbyte/sec to 1.3, if so it's hard to get excited about it. Some questions that come to mind: what was the message size? I would expect several measurements with different values. How did host CPU utilization change? What about latency? As we are competing with guest for host CPU, would worst-case or average latency suffer? Thanks, -- MST