Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755871AbbFOUIq (ORCPT ); Mon, 15 Jun 2015 16:08:46 -0400 Received: from mga09.intel.com ([134.134.136.24]:43815 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751479AbbFOUIj (ORCPT ); Mon, 15 Jun 2015 16:08:39 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,620,1427785200"; d="scan'208";a="711453394" Date: Mon, 15 Jun 2015 13:07:44 -0700 From: Jacob Pan To: Vince Weaver Cc: LKML , Peter Zijlstra , "H. Peter Anvin" , Stephane Eranian , Paul Mackerras , Andi Kleen , Thomas Gleixner , Arnaldo Carvalho de Melo Subject: Re: [PATCH v3] perf/rapl: support per domain energy unit Message-ID: <20150615130744.338995e0@icelake> In-Reply-To: References: Organization: OTC X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1664 Lines: 40 On Mon, 15 Jun 2015 13:32:01 -0400 (EDT) Vince Weaver wrote: > On Thu, 26 Mar 2015, Jacob Pan wrote: > > > RAPL energy hardware unit can vary within a single CPU package, e.g. > > HSW server DRAM has a fixed energy unit of 15.3 uJ (2^-16) whereas > > the unit on other domains can be enumerated from power unit MSR. > > There might be other variations in the future, this patch adds > > per cpu model quirk to allow special handling of certain cpus. > > So I have a Desktop Haswell machine (model 60) that is instrumented > to measure actual DRAM power at the DIMM (with a sense resistor). > > We are consistently getting RAPL results roughly a factor of 2 > smaller than the actual, measured results. > > Does desktop Haswell have a similar units issue to Haswell-EP? > Not that I know of. perhaps has to do with the difference of what and where we are measuring. Let me find a instrumented system to verify and get back to you. > I wasted a bunch of time trying to decode the > DRAM_ENERGY_SCALEFACTOR_MCHBAR values described in the > Desktop 4th Generation Intel Core Processor Family > datasheet but possibly that value in the MCHBAR is unrelated to the > one exported by the RAPL interface. > This scale factor is not directly related to the energy counter. The MMIO DRAM RAPL energy status uses the same unit as the MSR interface, the resolution is ~61uJ. > Vince [Jacob Pan] -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/