From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754788AbZIKQhc (ORCPT ); Fri, 11 Sep 2009 12:37:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754732AbZIKQhc (ORCPT ); Fri, 11 Sep 2009 12:37:32 -0400 Received: from brick.kernel.dk ([93.163.65.50]:41190 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754705AbZIKQhb (ORCPT ); Fri, 11 Sep 2009 12:37:31 -0400 Date: Fri, 11 Sep 2009 18:37:34 +0200 From: Jens Axboe To: Arjan van de Ven Cc: linux-kernel@vger.kernel.org, lenb@kernel.org, mingo@elte.hu, akpm@linux-foundation.org, peterz@infradead.org, yanmin_zhang@linux.intel.com, torvalds@linux-foundation.org Subject: Re: PATCH] cpuidle: A new variant of the menu governor to boost IO performance Message-ID: <20090911163733.GL14984@kernel.dk> References: <20090911174019.1ed02737@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090911174019.1ed02737@infradead.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 11 2009, Arjan van de Ven wrote: > From: Arjan van de Ven > Subject: [PATCH] cpuidle: A new variant of the menu governor > > This patch adds a new idle governor which balances power savings, > energy efficiency and performance impact. > > The reason for a reworked governor is that there have been > serious performance issues reported with the existing code > on Nehalem server systems. > > To show this I'm sure Andrew wants to see benchmark results: > (benchmark is "fio", "no cstates" is using "idle=poll") > > no cstates current linux new algorithm > 1 disk 107 Mb/s 85 Mb/s 105 Mb/s > 2 disks 215 Mb/s 123 Mb/s 209 Mb/s > 12 disks 590 Mb/s 320 Mb/s 585 Mb/s Heh that's interesting, I have noticed some oddities that I haven't pursued further yet. But it was definitely power state related, so I'll give your patch spin. -- Jens Axboe