From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: Re: acpi-cpufreq; Intel Johnstown (Atom N270) Date: Thu, 13 Aug 2009 15:07:41 -0400 Message-ID: <20090813190741.GA7808@redhat.com> References: <20090813172556.GB9385@alittletooquiet.net> <20090813182908.GC9385@alittletooquiet.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx2.redhat.com ([66.187.237.31]:42728 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755373AbZHMTHt (ORCPT ); Thu, 13 Aug 2009 15:07:49 -0400 Content-Disposition: inline In-Reply-To: <20090813182908.GC9385@alittletooquiet.net> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Forest Bond Cc: linux-acpi@vger.kernel.org On Thu, Aug 13, 2009 at 02:29:08PM -0400, Forest Bond wrote: > Hi, > > On Thu, Aug 13, 2009 at 01:25:57PM -0400, Forest Bond wrote: > > I'm using an Intel Johnstown board with an Atom N270 processor. Performance > > seems to improve dramatically with acpi-cpufreq loaded. This caught me by > > surprise. I had assumed that without loading acpi-cpufreq the CPU would be > > running at its maximum speed all the time. > > I ran some tests to get some numbers. My findings indicate that before > acpi-cpufreq is loaded the CPU is running at 800MHz even though /proc/cpuinfo > indicates 1.6GHz. if no cpufreq modules have been loaded, the CPU will be running at whatever p-state the BIOS programmed it to start up at. In your case for some reason, that's the 'slow' speed. Dave