Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932199AbZLENIi (ORCPT ); Sat, 5 Dec 2009 08:08:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755246AbZLENIh (ORCPT ); Sat, 5 Dec 2009 08:08:37 -0500 Received: from e31.co.us.ibm.com ([32.97.110.149]:42223 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755218AbZLENIe (ORCPT ); Sat, 5 Dec 2009 08:08:34 -0500 Date: Sat, 5 Dec 2009 18:38:28 +0530 From: Bharata B Rao To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Dhaval Giani , Balbir Singh , Vaidyanathan Srinivasan , Gautham R Shenoy , Srivatsa Vaddagiri , Kamalesh Babulal , Ingo Molnar , Pavel Emelyanov , Herbert Poetzl , Avi Kivity , Chris Friesen , Paul Menage , Mike Waychison Subject: Re: [RFC v4 PATCH 6/7] sched: Rebalance cfs runtimes Message-ID: <20091205130828.GC6204@in.ibm.com> Reply-To: bharata@linux.vnet.ibm.com References: <20091117143306.GK17335@in.ibm.com> <20091117143718.GQ17335@in.ibm.com> <1259942998.17907.897.camel@laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1259942998.17907.897.camel@laptop> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2040 Lines: 43 On Fri, Dec 04, 2009 at 05:09:58PM +0100, Peter Zijlstra wrote: > On Tue, 2009-11-17 at 20:07 +0530, Bharata B Rao wrote: > > sched: CFS runtime borrowing > > > > From: Bharata B Rao > > > > Before throttling a group, try to borrow runtime from groups that have excess. > > > > To start with, a group will get equal runtime on every cpu. If the group doesn't > > have tasks on all cpus, it might get throttled on some cpus while it still has > > runtime left on other cpus where it doesn't have any tasks to consume that > > runtime. Hence there is a chance to borrow runtimes from such cpus/cfs_rqs to > > cpus/cfs_rqs where it is required. > > > > CHECK: RT seems to be handling runtime initialization/reclaim during hotplug > > from multiple places (migration_call, update_runtime). Need to check if CFS > > also needs to do the same. > > > > Signed-off-by: Kamalesh Babulal > > --- > > kernel/sched.c | 26 ++++++++ > > kernel/sched_fair.c | 172 +++++++++++++++++++++++++++++++++++++++++++++++++++ > > kernel/sched_rt.c | 26 +------- > > 3 files changed, 202 insertions(+), 22 deletions(-) > > I think that if we unify the se/rq bandwidth structures a lot of copy > and paste can be avoided, resulting in an over-all much easier to > maintain code-base. As you note here and also in reply to 2/7, I could definetely unify some of the bandwidth handling code b/n rt and cfs. In fact I already have patches from Dhaval for this. I was holding them back till now since I wanted to show how cfs hard limits looks like and what changes it involves and get review feedback on them. As I have said in my earlier posts, I will eventually merge code with rt. I shall do this starting from next post. Regards, Bharata. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/