From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262655AbVG2Qlk (ORCPT ); Fri, 29 Jul 2005 12:41:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262653AbVG2Qld (ORCPT ); Fri, 29 Jul 2005 12:41:33 -0400 Received: from mx1.elte.hu ([157.181.1.137]:9348 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S262655AbVG2QlZ (ORCPT ); Fri, 29 Jul 2005 12:41:25 -0400 Date: Fri, 29 Jul 2005 18:40:11 +0200 From: Ingo Molnar To: Nick Piggin Cc: "Chen, Kenneth W" , linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org Subject: Re: Delete scheduler SD_WAKE_AFFINE and SD_WAKE_BALANCE flags Message-ID: <20050729164011.GA12138@elte.hu> References: <200507290627.j6T6Rrg06842@unix-os.sc.intel.com> <42E9ED47.1030003@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42E9ED47.1030003@yahoo.com.au> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Nick Piggin wrote: > Chen, Kenneth W wrote: > >Nick Piggin wrote on Thursday, July 28, 2005 7:01 PM > > >This clearly outlines an issue with the implementation. Optimize for one > >type of workload has detrimental effect on another workload and vice versa. > > > > Yep. That comes up fairly regularly when tuning the scheduler :( in this particular case we can clearly separate the two workloads though: CPU-overload (Ken's benchmark) vs. half-load (3-task tbench). So by checking for migration target/source idleness we can have a hard separator for wakeup balancing. (whether it works out for both types of workloads remains to be seen) Ingo