Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763067AbYBUJmj (ORCPT ); Thu, 21 Feb 2008 04:42:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751176AbYBUJmc (ORCPT ); Thu, 21 Feb 2008 04:42:32 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:38255 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751103AbYBUJma (ORCPT ); Thu, 21 Feb 2008 04:42:30 -0500 Date: Thu, 21 Feb 2008 10:42:17 +0100 From: Ingo Molnar To: Balbir Singh Cc: Peter Zijlstra , "Zhang, Yanmin" , Srivatsa Vaddagiri , Dhaval Giani , linux-kernel@vger.kernel.org Subject: Re: Make yield_task_fair more efficient Message-ID: <20080221094217.GA24162@elte.hu> References: <20080221053321.GA26918@balbir.in.ibm.com> <20080221060427.GA9159@elte.hu> <47BD1F75.5030506@linux.vnet.ibm.com> <20080221070733.GA13694@elte.hu> <47BD2A99.3010608@linux.vnet.ibm.com> <1203583439.6243.119.camel@lappy> <47BD3B56.3090404@linux.vnet.ibm.com> <20080221090430.GA20055@elte.hu> <47BD44FF.7070104@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47BD44FF.7070104@linux.vnet.ibm.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 937 Lines: 22 * Balbir Singh wrote: > I have an alternate approach in mind (that I need to find time for), > threaded-rbtrees. Walking the tree is really efficient, specially > finding successor of a node. sure, feel free to experiment with those details. But if you want to improve Java workloads then you should probably start by converting them to futexes instead of sched_yield(), that will probably give far more performance than micro-optimizing the sys_sched_yield() codepath. (especially when it happens at the expense of other workloads, which is not acceptable for mainline) You can rebuild your JVM easily and re-test with its locking fixed, right? Ingo -- 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/