From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261609AbVHBQL5 (ORCPT ); Tue, 2 Aug 2005 12:11:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261646AbVHBQJk (ORCPT ); Tue, 2 Aug 2005 12:09:40 -0400 Received: from smtp3.nextra.sk ([195.168.1.142]:32267 "EHLO mailhub3.nextra.sk") by vger.kernel.org with ESMTP id S261651AbVHBQIu (ORCPT ); Tue, 2 Aug 2005 12:08:50 -0400 Message-ID: <42EF9A8E.8020302@rainbow-software.org> Date: Tue, 02 Aug 2005 18:08:46 +0200 From: Ondrej Zary User-Agent: Mozilla Thunderbird 1.0.6 (X11/20050716) X-Accept-Language: en-us, en MIME-Version: 1.0 To: James Bruce CC: sclark46@earthlink.net, linux-kernel@vger.kernel.org Subject: Re: Power consumption HZ100, HZ250, HZ1000: new numbers References: <20050730195116.GB9188@elf.ucw.cz> <1122753864.14769.18.camel@mindpipe> <20050730201049.GE2093@elf.ucw.cz> <42ED32D3.9070208@andrew.cmu.edu> <20050731211020.GB27433@elf.ucw.cz> <42ED4CCF.6020803@andrew.cmu.edu> <20050731224752.GC27580@elf.ucw.cz> <1122852234.13000.27.camel@mindpipe> <20050801074447.GJ9841@khan.acc.umu.se> <42EE4B4A.80602@andrew.cmu.edu> <20050801204245.GC17258@thunk.org> <42EEFB9B.10508@andrew.cmu.edu> <42EF70BD.7070804@earthlink.net> <42EF947E.1070600@andrew.cmu.edu> In-Reply-To: <42EF947E.1070600@andrew.cmu.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org James Bruce wrote: > Stephen Clark wrote: > >> Maybe new desktop systems - but what about the tens of millions of old >> systems that don't. > > > If it's an old system, it probably doesn't have working ACPI C-states > though. Without that, low HZ does not save you anything. I should have > said: 99% of desktops with the capability to do ACPI sleep have at least > one USB device attached (usually a mouse). rainbow@pentium:~$ cat /proc/acpi/processor/CPU0/power active state: C2 max_cstate: C8 bus master activity: 00000000 states: C1: type[C1] promotion[C2] demotion[--] latency[000] usage[00052470] *C2: type[C2] promotion[--] demotion[C1] latency[090] usage[02699149] This is PCPartner TXB820DS motherboard (Socket 7, i430TX) with 1998 Award BIOS and C-states seem to work fine. I've tested it in Windows 98 some time ago - the CPU is almost cold when idle with ACPI enabled and hot with ACPI disabled (that's partly caused by the fact that Windows 9x does not HLT the CPU when idle). With Pentium 100MHz in the socket and ACPI enabled, I could even touch the CPU (without heatsink) without burning my fingers. -- Ondrej Zary