From owner-freebsd-mobile@FreeBSD.ORG Sun Nov 2 22:27:25 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 6E5F91065672; Sun, 2 Nov 2008 22:27:25 +0000 (UTC) (envelope-from gaijin.k@gmail.com) Received: from qw-out-2122.google.com (qw-out-2122.google.com [74.125.92.24]) by mx1.freebsd.org (Postfix) with ESMTP id DE1408FC16; Sun, 2 Nov 2008 22:27:24 +0000 (UTC) (envelope-from gaijin.k@gmail.com) Received: by qw-out-2122.google.com with SMTP id 9so905059qwb.7 for ; Sun, 02 Nov 2008 14:27:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:from:to:cc :in-reply-to:references:content-type:date:message-id:mime-version :x-mailer:content-transfer-encoding; bh=nVC+Y1CWKgzYNAGbkedDJyo+zCC0Hfk4AyWTF9uxktA=; b=jjvp+TIepiAPSYLNrKX0smdUy4qT3vXqlRuTZBbUnc2hpocBkMmUsHUl8R8iLbeCvm CzUCWcwgKlGT9OwbpWKCP2BGnuqzD99gMa8sCInJ8lJ9x/qSBVDDhjRx//6zeFWN1DfI 4TzVPF6m0qiea4L/qLSC8YX0gX7mPtxQWAtMo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=BzEwloDtgmz7xI8xTU3BmGLfwfRoc20dMWHZTUxMuFLFGkLCoBEVg0TO6VeeDACDFe PHCtO9qIc/KCWTdNCkGwTTyCRwmndS/8k4tOAjsoyBYpsCXfADJQN1bX7VqIi9xobKDP axOzJU6WjZfE8q4cJ0hM1332f4CTFlWY/uH1I= Received: by 10.214.45.12 with SMTP id s12mr2795581qas.160.1225664844239; Sun, 02 Nov 2008 14:27:24 -0800 (PST) Received: from ?10.0.3.231? ([70.111.21.88]) by mx.google.com with ESMTPS id 8sm5634435ywg.6.2008.11.02.14.27.23 (version=SSLv3 cipher=RC4-MD5); Sun, 02 Nov 2008 14:27:23 -0800 (PST) From: "Alexandre \"Sunny\" Kovalenko" To: Alexander Motin In-Reply-To: <490E245C.7070900@FreeBSD.org> References: <490DF584.5080506@FreeBSD.org> <1225656933.1202.2.camel@RabbitsDen> <490E245C.7070900@FreeBSD.org> Content-Type: text/plain; charset=utf-8 Date: Sun, 02 Nov 2008 17:26:53 -0500 Message-Id: <1225664813.1202.5.camel@RabbitsDen> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 FreeBSD GNOME Team Port Content-Transfer-Encoding: 8bit Cc: FreeBSD acpi , freebsd-mobile@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: Sun, 02 Nov 2008 22:27:25 -0000 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? -- Alexandre "Sunny" Kovalenko (Олександр Коваленко)