From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1N2VgW-00040D-6R for garchives@archives.gentoo.org; Mon, 26 Oct 2009 19:56:56 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 45D6CE0866; Mon, 26 Oct 2009 19:56:21 +0000 (UTC) Received: from mail-yw0-f191.google.com (mail-yw0-f191.google.com [209.85.211.191]) by pigeon.gentoo.org (Postfix) with ESMTP id 291B5E0866 for ; Mon, 26 Oct 2009 19:56:21 +0000 (UTC) Received: by ywh29 with SMTP id 29so10345836ywh.32 for ; Mon, 26 Oct 2009 12:56:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=Gmn8WkjYKtxrqU7Zj8trqyGImv3w3i1Tpc5MhdB7twM=; b=Im3vuKDTB/E6wBHmcLJS2gUR0qdkAUC96NEJa92Hz2ceSaGfjWqnvaoYJhWrobVkmd 4xJzDYlPOxaNM+hlgnPRf+M1FR066UTHWTMiNuzjnPHXsCe/8qPjSGssm8AhlY0QEOoz HTnSfFYeNmweKlZ6IHz1baKSUpyq8vJSUwXc8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=eor0pYbUXqmmRMBTOs/kgVuvT6HJ0Q2jNfP5jduxdIOE/XrtVLSW2vhL1P+1ZnWySx XOMK+O28lofupyUookpuV4/vqNXiHJCgJN2Gj5uJ74fyWidVW/2fePleMLSz1nQnezlj pE2DKeY0rdi3UPJgo29dF4UjeX+r0b9Z8DUrc= Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Sender: paul.hartman@gmail.com Received: by 10.150.24.4 with SMTP id 4mr24680767ybx.67.1256586980920; Mon, 26 Oct 2009 12:56:20 -0700 (PDT) In-Reply-To: <49bf44f10910261244q218add8araa11fb56c7998d52@mail.gmail.com> References: <49bf44f10910251437q530ddecdv4a669d2587e70f79@mail.gmail.com> <49bf44f10910261244q218add8araa11fb56c7998d52@mail.gmail.com> Date: Mon, 26 Oct 2009 14:56:20 -0500 X-Google-Sender-Auth: 899bcebb0ea6477e Message-ID: <58965d8a0910261256j659ce61bufd008885efd9a815@mail.gmail.com> Subject: Re: [gentoo-user] Re: lm_sensors much hotter in 2.6.31 than 2.6.28 From: Paul Hartman To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset=ISO-8859-1 X-Archives-Salt: f0edff18-2cf9-4a21-9e62-69a15005315f X-Archives-Hash: b0e817f0044ebe11a4029ad1e57274a5 On Mon, Oct 26, 2009 at 2:44 PM, Grant wrote: >>> After upgrading from 2.6.28 to 2.6.31, I noticed my CPU temperatures >>> are reported a full 20C hotter. If I load the old kernel, the >>> reported temperatures drops back down to normal. Has anyone else seen >>> this? >> >> If you're using coretemp as sensor, the temps are always off (the coretemp >> sensor of Intel chips is not accurate, not by any stretch of the >> imagination.) It only reports the distance to the CPU's maximum thermal >> junction, which then the coretemp driver *tries* to translate into a >> temperature, but the result is wrong since the value reported by the CPU is >> not accurate to start with (it only gets accurate as you approach the max >> value). That maximum value is totally undocumented for desktop CPUs (the >> docs Intel provided recently are wrong.) >> >> You should use your mainboard's sensors instead for accurate values. > > I'm actually using k8temp. Do you think it is susceptible to the same > problems you're talking about? I also have an ACPI sensor available > named THRM. Should that one be more accurate? > > BTW, another system of mine (Dell laptop) only seems to have available > coretemp or an ACPI sensor which reports values like 46960 mWh. Am I > totally out of luck with that one? > > So, In the end, it's fairly impossible to monitor a CPU's actual > temperature in order to keep it below the published maximum? Hmm, the k8temp documentation seems to indicate that it should be actual temperature: "Temperatures are measured in degrees Celsius and measurement resolution is 1 degree C. It is expected that future CPU will have better resolution. The temperature is updated once a second. Valid temperatures are from -49 to 206 degrees C." Also, with lm_sensors not all sensors can be auto-detected. I had to manually specify mine (Abit uGuru3).