From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755564AbbAORNM (ORCPT ); Thu, 15 Jan 2015 12:13:12 -0500 Received: from mga03.intel.com ([134.134.136.65]:59788 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754760AbbAORNG (ORCPT ); Thu, 15 Jan 2015 12:13:06 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,404,1418112000"; d="scan'208";a="512812322" Message-ID: <1421341986.2399.23.camel@schen9-desk2.jf.intel.com> Subject: Re: [PATCH] Repost sched-rt: Reduce rq lock contention by eliminating locking of non-feasible target From: Tim Chen To: Peter Zijlstra , Steven Rostedt Cc: Ingo Molnar , Andi Kleen , Shawn Bohrer , Suruchi Kadu , Doug Nelson , linux-kernel@vger.kernel.org, Juri Lelli Date: Thu, 15 Jan 2015 09:13:06 -0800 In-Reply-To: <20150106193025.GD23965@worktop.programming.kicks-ass.net> References: <1420570911.2399.4.camel@schen9-desk2.jf.intel.com> <20150106193025.GD23965@worktop.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.8.5 (3.8.5-2.fc19) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2015-01-06 at 20:30 +0100, Peter Zijlstra wrote: > On Tue, Jan 06, 2015 at 11:01:51AM -0800, Tim Chen wrote: > > Didn't get any response for this patch probably due to the holidays. > > Reposting it as we will like to get it merged to help our database > > workload. > > > > This patch added checks that prevent futile attempts to move rt tasks > > to cpu with active tasks of equal or higher priority. This reduces > > run queue lock contention and improves the performance of a well > > known OLTP benchmark by 0.7%. > > Don't immediately see anything wrong with this, Steve? Steve, do you have any objections to this patch? Thanks. Tim