From owner-freebsd-mobile@FreeBSD.ORG Thu Nov 20 21:33:08 2008 Return-Path: Delivered-To: freebsd-mobile@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E9D361065674 for ; Thu, 20 Nov 2008 21:33:08 +0000 (UTC) (envelope-from freebsd-mobile@m.gmane.org) Received: from ciao.gmane.org (main.gmane.org [80.91.229.2]) by mx1.freebsd.org (Postfix) with ESMTP id 6FDE78FC1D for ; Thu, 20 Nov 2008 21:33:08 +0000 (UTC) (envelope-from freebsd-mobile@m.gmane.org) Received: from list by ciao.gmane.org with local (Exim 4.43) id 1L3H97-0003U2-6F for freebsd-mobile@freebsd.org; Thu, 20 Nov 2008 21:33:05 +0000 Received: from 200.41.broadband11.iol.cz ([90.178.41.200]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 20 Nov 2008 21:33:05 +0000 Received: from gamato by 200.41.broadband11.iol.cz with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 20 Nov 2008 21:33:05 +0000 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-mobile@freebsd.org From: martinko Date: Thu, 20 Nov 2008 22:32:57 +0100 Lines: 56 Message-ID: References: <490DF584.5080506@FreeBSD.org> <1225656933.1202.2.camel@RabbitsDen> <490E245C.7070900@FreeBSD.org> <1225664813.1202.5.camel@RabbitsDen> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 200.41.broadband11.iol.cz User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.17) Gecko/20081009 SeaMonkey/1.1.12 In-Reply-To: <1225664813.1202.5.camel@RabbitsDen> Sender: news Cc: freebsd-acpi@freebsd.org Subject: Re: Is the C3 possible with SMP? X-BeenThere: freebsd-mobile@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Mobile computing with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 20 Nov 2008 21:33:09 -0000 Alexandre "Sunny" Kovalenko wrote: > On Mon, 2008-11-03 at 00:06 +0200, Alexander Motin wrote: >> Alexandre "Sunny" Kovalenko wrote: >>>> I have tried to enable C3 state on my Core2Duo laptop and found that it >>>> is not working good. System HZ timer stops during CPU sleep. After some >>>> investigation I have found that it is due to LAPIC timer used for HZ >>>> stopped during C3 state (same as during AMD's C1E). >>>> >>>> So the question is: Is it possible (or planned) to make it work somehow? >>>> For example, by using some external timer instead of LAPIC's one? >>>> >>>> ACPI reports about 20% less idle power consumption with C3 state >>>> comparing to C2. It would be interesting to get additional half an hour >>>> on battery. >>>> >>> You can get half way there by adding >>> >>> dev.cpu.1.cx_lowest=C3 >>> >>> to /etc/sysctl.conf >> Thanks. >> >> 1. Looks like it does not kill the timer. >> 2. I haven't got any benefit from it in idle state. According to >> `acpiconf -i 0` I have about 13 Amps (IMHO more looks like Watts) with >> both C2 and this half-to-C3, but only 11 Amps in full C3 (but without >> timer). >> 3. I have got about 10% benefit (33 Amps against 36) when cpu0 is 100% >> busy while cpu1 is idle. >> > You would not happen to have USB loaded or built into kernel? If you do, > you will practically never go into C3. What does > > sysctl dev.cpu | grep cx_usage > > say? > Hi, My laptop reports C1 state only: $ sysctl -a | grep cx_ hw.acpi.cpu.cx_lowest: C1 dev.cpu.0.cx_supported: C1/1 dev.cpu.0.cx_lowest: C1 dev.cpu.0.cx_usage: 100.00% But this is Pentium-M and I remember it could use C2 and C3 back with 5.x kernel and I'm sure I had USB as I have now. Do you have any idea why I don't have C2/C3 states available anymore ?? Cheers, Martin