From owner-freebsd-amd64@FreeBSD.ORG Tue Nov 12 12:24:28 2013 Return-Path: Delivered-To: freebsd-amd64@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E55F5BDE for ; Tue, 12 Nov 2013 12:24:27 +0000 (UTC) Received: from nm18-vm9.bullet.mail.ir2.yahoo.com (nm18-vm9.bullet.mail.ir2.yahoo.com [212.82.96.233]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id E4E7527E0 for ; Tue, 12 Nov 2013 12:24:26 +0000 (UTC) Received: from [212.82.98.58] by nm18.bullet.mail.ir2.yahoo.com with NNFMP; 12 Nov 2013 12:24:18 -0000 Received: from [46.228.39.65] by tm11.bullet.mail.ir2.yahoo.com with NNFMP; 12 Nov 2013 12:24:18 -0000 Received: from [127.0.0.1] by smtp102.mail.ir2.yahoo.com with NNFMP; 12 Nov 2013 12:24:18 -0000 X-Yahoo-Newman-Id: 766564.46046.bm@smtp102.mail.ir2.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: XZbipLsVM1lTOKimX5xuyG6iPiX1o.WxOe4vsDUNfEuSfhi b0958K8ktKicXdOfQKhooioik85bNeGUmzee1f5vzv0vj6PhBu9XYXQd.CJp F.KIxudF4kgwQd4JtKQWFD8omjs7ti.vU2Mxpzx6_Cj70w5kLqFAmFKgXj.5 yBJre3fo.h.wCMUGhMDimLe2H1SkzEOAmP.IQhumRVhJnY4EmmAQvzCMxe1p USLu7rgrrNPhhbYo2a2zbRm9e.z_8XGOM9IUOBRRDXJmLXL8v.qYq2mqmu45 5Z6yR504VEK01Ra7FqcwADFNNYWD0zK6x8.0X1WSuFOi1LSq1sKvbjWErSXL KY_WGT9BsEYkbGUWODoscYK1bKFPhP3NBDiwhiOTAZFjbAeRbFqpHCUNRJOM k7TCM2zQUYxexP4PeFnWHZfiOrtrGU1Zj5yyFSB1do_14LDMVv_onm1CEVL7 Cpj2JTdy3DSELSlueIvlccn7kgOVYeD.HZeD5UgLZb6i_PvCFMSRQfuq_CLQ WZOkVhDTTDkaL0zjcjuRDRijJAaIhlriqFwTpT3htQxXu.MIh6Qfo3U5K0_D 4590R7MbnpfgisN_acrGj42L0GSsyoQy3kgEXUAxRfSsWm3K2z9wphrGwFkJ 5YVGHY2aKtrYEBvJ_dHtkxFH8qYv3IihBlXGEMBVCC1ERrEW6ssN3Iqfg2u5 JPBM1_h_rrFCO X-Yahoo-SMTP: iDf2N9.swBDAhYEh7VHfpgq0lnq. X-Rocket-Received: from [192.168.119.11] (se@84.154.101.118 with ) by smtp102.mail.ir2.yahoo.com with SMTP; 12 Nov 2013 12:24:18 +0000 UTC Message-ID: <52821DED.5010002@freebsd.org> Date: Tue, 12 Nov 2013 13:24:13 +0100 From: Stefan Esser User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: freebsd-amd64@freebsd.org Subject: Re: Problems with amd FX 8 core and freq scaling References: <1384119989.1540.9.camel@freebsd.local> <5280A76B.20307@freebsd.org> <5281358D.1010406@FreeBSD.org> In-Reply-To: <5281358D.1010406@FreeBSD.org> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-amd64@freebsd.org X-Mailman-Version: 2.1.16 Precedence: list List-Id: Porting FreeBSD to the AMD64 platform List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Nov 2013 12:24:28 -0000 Am 11.11.2013 20:52, schrieb Jung-uk Kim: > On 2013-11-11 13:16:47 -0500, Nicholas McKenzie wrote: >> But wouldn't this just disable frequency scaling and the whole >> point of powerd? > > No. acpi_throttle (and p4tcc) controls T-state. "Frequency > scaling" should be done by changing P-state. > >> On Mon, Nov 11, 2013 at 1:46 AM, Stefan Esser >> wrote: >>> >>> Am 10.11.2013 22:46, schrieb Nicholas Stewart McKenzie: >>>> My computer crashes if I enable powerd. I can't get cpu freq >>>> scaling to work with my cpu:(P.S. I sent this to both >>>> drivers and amd64 mailing list... >>> >>> Hi, >>> >>> you may want to try booting with the following line added to >>> /boot/loader.conf (or entered at the boot menu prompt after >>> breaking out of automatic boot): >>> >>> hint.acpi_throttle.0.disabled="1" >>> >>> There have been a number of reports of throttling causing >>> crashes. This setting does not prevent powerd from adjusting >>> your CPU's clock, it just disables some arcane feature which >>> pre-dates the modern power management methods. > > I rewrote acpi_throttle.c at some point to fix the problem but > never committed it because nobody was really interested in testing > the patch. Also, it is really an arcane and archaic feature: > > http://software.intel.com/en-us/blogs/2013/10/15/c-states-p-states-where-the-heck-are-those-t-states > > Now I think we should disable the feature by default because it > is causing too much hassle for us (attached). Any objection? No objections from me ... IIRC, there was consensus that throttling should be disabled when this was last discussed, years ago. There might be some P-4 systems in use today, but AFAIK they do not need support from the OS to prevent them from over-heating (which was all that throttling could achieve). I'm very much in favour of setting throttling to disabled even for 10.0. Throttling has no use, but can cause crashes or undesired behaviour (in combination with P-states the effective CPU clock may be a magnitude lower than necessary for the least power consuming P-state). BTW: Throttling should not only be disabled for amd64 but also for i386, IMHO. Regards, STefan