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 19:54:21 +0300 Message-ID: <49D4EDBD.3050900@redhat.com> References: <20090402085253.GA29932@gondor.apana.org.au> <49D487A6.407@redhat.com> <49D49C1F.6030306@novell.com> <200904022243.21088.rusty@rustcorp.com.au> <49D4B4A3.5070008@novell.com> <49D4B87D.2000202@redhat.com> <20090402145018.GA816@gondor.apana.org.au> <49D4D301.2090209@redhat.com> <20090402154041.GA1774@gondor.apana.org.au> <49D4E072.2060003@redhat.com> <20090402160941.GB2173@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Gregory Haskins , Rusty Russell , anthony@codemonkey.ws, andi@firstfloor.org, linux-kernel@vger.kernel.org, agraf@suse.de, pmullaney@novell.com, pmorreale@novell.com, netdev@vger.kernel.org, kvm@vger.kernel.org, Ingo Molnar To: Herbert Xu Return-path: In-Reply-To: <20090402160941.GB2173@gondor.apana.org.au> Sender: kvm-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Herbert Xu wrote: > On Thu, Apr 02, 2009 at 06:57:38PM +0300, Avi Kivity wrote: > >> What if the guest sends N packets, then does some expensive computation >> (say the guest scheduler switches from the benchmark process to >> evolution). So now we have the marker set at packet N, but the host >> will not see it until the guest timeslice is up? >> > > Well that's fine. The guest will use up the remainder of its > timeslice. After all we only have one core/hyperthread here so > this is no different than if the packets were held up higher up > in the guest kernel and the guest decided to do some computation. > > 3ms latency for ping? (ping will always be scheduled immediately when the reply arrives if I understand cfs, so guest load won't delay it) -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.