From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4DD0C433F5 for ; Sun, 6 Feb 2022 08:35:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231946AbiBFIff (ORCPT ); Sun, 6 Feb 2022 03:35:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231391AbiBFIfe (ORCPT ); Sun, 6 Feb 2022 03:35:34 -0500 X-Greylist: delayed 64 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Sun, 06 Feb 2022 00:35:33 PST Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A34BC06173B for ; Sun, 6 Feb 2022 00:35:33 -0800 (PST) X-IronPort-AV: E=Sophos;i="5.88,347,1635199200"; d="scan'208";a="5130966" Received: from 173.121.68.85.rev.sfr.net (HELO hadrien) ([85.68.121.173]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Feb 2022 09:34:27 +0100 Date: Sun, 6 Feb 2022 09:34:26 +0100 (CET) From: Julia Lawall X-X-Sender: jll@hadrien To: Zhang Rui cc: Len Brown , linux-pm@vger.kernel.org Subject: Re: DRAM power consumption with turbostat In-Reply-To: <44a1ea665bad28a8e2d314427d9c50c214e1a436.camel@intel.com> Message-ID: References: <44a1ea665bad28a8e2d314427d9c50c214e1a436.camel@intel.com> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Sun, 6 Feb 2022, Zhang Rui wrote: > Hi, Julia, > > Thanks for reporting this. > > On Sun, 2022-01-30 at 11:27 +0100, Julia Lawall wrote: > > Hello, > > > > I was wondering whether the DRAM power consumption reported by > > turbostat > > is reliable on recent Intel machines? > > > > In particular, I observed that turbostat reported a high DRAM energy > > comsumption on a machine (Intel 5128) > > are you sure it is 5128? google tells me that 5128 is pretty old, in > around 2006. Oops! 5218 Thanks for the pointer to the new version. I will try that. julia > > can you please paste the lscpu output? > > > with persistent memory, but where > > the persistent memory was not being used. A colleague did an > > experiemnt > > on another machine with persistent memory, and reported: > > > > ----- > > > > I didn't run the test on troll but on another server equipped with PM > > where I was able to reproduce the bug and by reading directly the msr > > registers, I see that: > > CPU Energy units = 0.00006104J > > DRAM Energy units = 0.00001526J > > > > However turbostat assumes that the DRAM Energy units is 0.00006104J > > when > > it runs the computation to obtain Joules (hence the too-high value > > returned by turbostat) > > And can you please try latest version of turbostat? > > The problem should be fixed by the below commit > > commit abdc75ab53b7fd2ef42c79e88cf0caf2d007c4f2 > Author: Zhang Rui > AuthorDate: Thu Mar 11 10:05:13 2021 +0800 > Commit: Len Brown > CommitDate: Tue May 4 18:23:14 2021 -0400 > > tools/power turbostat: Fix DRAM Energy Unit on SKX > > SKX uses fixed DRAM Energy Unit, just like HSX and BDX. > > Signed-off-by: Zhang Rui > Signed-off-by: Len Brown > > thanks, > rui > > > > ----- > > > > I see the code in turbostat that just uses the CPU energy units value > > (rapl_dram_energy_units_probe), but I don't know what was the MSR > > used to > > collect the above information. Overall, I am wondering if the DRAM > > energy > > consumption values are reliable in cases with and without persistent > > memory. > > > > thanks, > > julia > >