From owner-freebsd-stable@FreeBSD.ORG Fri May 22 17:26:43 2015 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 41C6EE3A for ; Fri, 22 May 2015 17:26:43 +0000 (UTC) Received: from mail-la0-x22b.google.com (mail-la0-x22b.google.com [IPv6:2a00:1450:4010:c03::22b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id BB1FA1270 for ; Fri, 22 May 2015 17:26:42 +0000 (UTC) Received: by labbd9 with SMTP id bd9so17178589lab.2 for ; Fri, 22 May 2015 10:26:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=NmKiXg6t8IiS4fjqIYDne3fKE6U3RhOONPX2Jcofrss=; b=ejrkp5csdq5HqB9OStIdRzpaqrSVoMorSpKXTM2eWpxJBvhMIksRD9wgGHMFdgKJ9f OWbj3w7hj+Ci2FQyEjtr6i+mMoBy+R44gaQuBrMyZ5ECDYIe0STrVg1rEle2kxExPF3N suiNv9dQfDo7Jb48/1zDH82SWkRSamugr+Q5Q1ZD8xNyL0X+Wxb+F713lbLFJNledlEZ sXooJtUDCIpG/Li15TvD14yNg8cC+BnXzIVtCbMjdiZuo5cWCLIf2Bzma47mD9jVAO6E kIu9ESiyWS5/d9lDVmegee4PiTSRhnRAWFpvoo6F3YNz9M+HLGfIR1YsgZjDimFeWx/u GPQA== MIME-Version: 1.0 X-Received: by 10.112.72.40 with SMTP id a8mr4371195lbv.58.1432315600717; Fri, 22 May 2015 10:26:40 -0700 (PDT) Received: by 10.152.137.193 with HTTP; Fri, 22 May 2015 10:26:40 -0700 (PDT) In-Reply-To: <20150523014640.K7173@sola.nimnet.asn.au> References: <555C71C8.4080007@gmx.com> <555EDBBB.4090107@gmx.com> <20150522104213.4e083225@nonamehost.local> <20150523014640.K7173@sola.nimnet.asn.au> Date: Fri, 22 May 2015 20:26:40 +0300 Message-ID: Subject: Re: CPU frequency doesn't drop below 1200MHz (like it used to) From: Kimmo Paasiala To: Ian Smith Cc: Ivan Klymenko , Nikos Vassiliadis , "freebsd-stable@freebsd.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 May 2015 17:26:43 -0000 On Fri, May 22, 2015 at 8:19 PM, Ian Smith wrote: > On Fri, 22 May 2015 16:28:49 +0300, Kimmo Paasiala wrote: > > On Fri, May 22, 2015 at 10:42 AM, Ivan Klymenko wrote: >> Fri, 22 May 2015 09:33:15 +0200 >> Nikos Vassiliadis =D1=8F=D1=8F=D1=8F=D1=8F=D1=8F=D1=8F= =D1=8F=D1=8F=D1=8F=D1=8F=D1=8F=D1=8F=D1=8F=D1=8F: >> >>> Hi, >>> >>> I just noticed that my CPU's frequency doesn't support dropping >>> below 1200MHz. It used to be able to go down to 150MHz, if I am >>> not mistaken. I'd like it to go down to 600MHz via powerd, like >>> it used to go. This is a month's old 10-STABLE. >>> >>> > [nik@moby ~]$ sysctl dev.cpu.0.freq_levels >>> > dev.cpu.0.freq_levels: 2400/35000 2300/32872 2200/31127 2100/29417 >>> > 2000/27740 1900/26096 1800/24490 1700/22588 1600/21045 1500/19534 >>> > 1400/18055 1300/16611 1200/15194 >>> >>> This is the CPU: >>> > hw.model: Intel(R) Core(TM) i3-3110M CPU @ 2.40GHz >>> >>> Thanks in advance for any ideas, >>> Nikos >> >> Try changing the options in /boot/device.hints >> hint.acpi_throttle.0.disabled=3D"0" >> hint.p4tcc.0.disabled=3D"0" > > > Thanks, those also fixed powerd(8) for me that stopped working after > > upgrading to stable/10 from releng/10.1. Why are those setting > > suddenly needed now? > > > > -Kimmo > > Looks like the changes to these two hints, now defaulting to 1, > committed to -head some months ago has been merged to stable/10. > > Can you say exactly in what way powerd stopped working then? Powerd(8) complained (excerpt from dmesg -a): Starting powerd. powerd: no cpufreq(4) support -- aborting: No such file or directory /etc/rc: WARNING: failed to start powerd Putting those two settings in loader.conf and rebooting fixed the problem and powerd started working again apparently because cpufreq(4) device was available again. -Kimmo > > Except that the minimum frequency that may be set with powerd's -m > switch will be higher without p4tcc (or acpi_throttle) running, this > change shouldn't hurt powerd; if anything it should be more efficient, > as the lower p4tcc-generated frequencies don't save much if any power. > > If you compare dev.cpu.0.freq_levels, as above, both before and after > booting with the changed hints, you can see the ones due to p4tcc's use > of subfrequencies with factors of 1/8 to 7/8 of some base freq, but the > power use in milliWatts provided for these seems largely ficticious. > > On my Lenovo X200, Core2Duo 2.4GHz, idling on battery at 800MHz (minimum > EST freq) or at 100MHz using p4tcc draws almost exactly the same power, > about 7.6W measured from the battery - but responsiveness as performance > is required is a great deal better using just the base EST freqs; YMMV. > > This generally gets discussed on the freebsd-mobile and freebsd-acpi > lists; not sure if a deeper discussion of issues is warranted here. > > cheers, Ian