From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFC PATCH 2/3] sched: add yield_to function Date: Fri, 03 Dec 2010 22:23:11 +0100 Message-ID: <1291411391.2032.4.camel@laptop> References: <20101202144129.4357fe00@annuminas.surriel.com> <20101202144423.3ad1908d@annuminas.surriel.com> <1291382619.32004.2124.camel@laptop> <20101203133056.GF27994@linux.vnet.ibm.com> <1291385010.32004.2165.camel@laptop> <20101203140607.GA9800@linux.vnet.ibm.com> <20101203141037.GE16411@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Cc: Rik van Riel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Avi Kiviti , Ingo Molnar , Anthony Liguori To: vatsa@linux.vnet.ibm.com Return-path: In-Reply-To: <20101203141037.GE16411@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Fri, 2010-12-03 at 19:40 +0530, Srivatsa Vaddagiri wrote: > On Fri, Dec 03, 2010 at 07:36:07PM +0530, Srivatsa Vaddagiri wrote: > > On Fri, Dec 03, 2010 at 03:03:30PM +0100, Peter Zijlstra wrote: > > > No, because they do receive service (they spend some time spinning > > > before being interrupted), so the respective vruntimes will increase, at > > > some point they'll pass B0 and it'll get scheduled. > > > > Is that sufficient to ensure that B0 receives its fair share (1/3 cpu in this > > case)? > > Hmm perhaps yes, althought at cost of tons of context switches, which would be > nice to minimize on? Don't care, as long as the guys calling yield_to() pay for that time its their problem.