From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262682AbVG2RdJ (ORCPT ); Fri, 29 Jul 2005 13:33:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262631AbVG2Ram (ORCPT ); Fri, 29 Jul 2005 13:30:42 -0400 Received: from fmr23.intel.com ([143.183.121.15]:25314 "EHLO scsfmr003.sc.intel.com") by vger.kernel.org with ESMTP id S262641AbVG2RaU (ORCPT ); Fri, 29 Jul 2005 13:30:20 -0400 Message-Id: <200507291730.j6THUCg15426@unix-os.sc.intel.com> From: "Chen, Kenneth W" To: "'Ingo Molnar'" Cc: "'Nick Piggin'" , , Subject: RE: Delete scheduler SD_WAKE_AFFINE and SD_WAKE_BALANCE flags Date: Fri, 29 Jul 2005 10:30:12 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook, Build 11.0.6353 Thread-Index: AcWUMG5fxrtMbb81SUyodAUzpB3O2gAMZbcQ In-Reply-To: <20050729112616.GA24965@elte.hu> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote on Friday, July 29, 2005 4:26 AM > * Chen, Kenneth W wrote: > > To demonstrate the problem, we turned off these two flags in the cpu > > sd domain and measured a stunning 2.15% performance gain! And > > deleting all the code in the try_to_wake_up() pertain to load > > balancing gives us another 0.2% gain. > > another thing: do you have a HT-capable ia64 CPU, and do you have > CONFIG_SCHED_SMT turned on? If yes then could you try to turn off > SD_WAKE_IDLE too, i found it to bring further performance improvements > in certain workloads. The scheduler experiments done so far are on non-SMT CPU (Madison processor). We have another db setup with multi-thread capable ia64 cpu (montecito, and to be precise, it is SOEMT capable). We are just about to do scheduler experiments on that setup.