From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC PATCH 00/17] virtual-bus Date: Thu, 02 Apr 2009 15:43:52 +0300 Message-ID: <49D4B308.2030007@redhat.com> References: <20090402085253.GA29932@gondor.apana.org.au> <49D47F11.6070400@redhat.com> <20090402091639.GA30126@gondor.apana.org.au> <49D484F5.2000400@redhat.com> <20090402092936.GA30333@gondor.apana.org.au> <49D487A6.407@redhat.com> <49D49C1F.6030306@novell.com> <49D4A89E.5090407@redhat.com> <49D4AFF7.1050603@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Herbert Xu , anthony@codemonkey.ws, andi@firstfloor.org, linux-kernel@vger.kernel.org, agraf@suse.de, pmullaney@novell.com, pmorreale@novell.com, rusty@rustcorp.com.au, netdev@vger.kernel.org, kvm@vger.kernel.org, Mark McLoughlin To: Gregory Haskins Return-path: Received: from mx2.redhat.com ([66.187.237.31]:48492 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755972AbZDBMoK (ORCPT ); Thu, 2 Apr 2009 08:44:10 -0400 In-Reply-To: <49D4AFF7.1050603@novell.com> Sender: netdev-owner@vger.kernel.org List-ID: Gregory Haskins wrote: >> It's more of a "schedule and forget" which I think brings you the >> win. The host disables notifications and schedules the actual tx work >> (rx from the host's perspective). So now the guest and host continue >> producing and consuming packets in parallel. So long as the guest is >> faster (due to the host being throttled?), notifications continue to >> be disabled. >> > Yep, when the "producer::consumer" ratio is > 1, we mitigate signaling. > When its < 1, we signal roughly once per packet. > > >> If you changed your rx_isr() to process the packets immediately >> instead of scheduling, I think throughput would drop dramatically. >> > Right, that is the point. :) This is that "soft asic" thing I was > talking about yesterday. > But all that has nothing to do with where the code lives, in the kernel or userspace. -- error compiling committee.c: too many arguments to function