From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754296AbaCRI3X (ORCPT ); Tue, 18 Mar 2014 04:29:23 -0400 Received: from terminus.zytor.com ([198.137.202.10]:45556 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754262AbaCRI3T (ORCPT ); Tue, 18 Mar 2014 04:29:19 -0400 Date: Tue, 18 Mar 2014 01:28:55 -0700 From: tip-bot for Andi Kleen Message-ID: Cc: acme@redhat.com, linux-kernel@vger.kernel.org, eranian@google.com, hpa@zytor.com, mingo@kernel.org, ak@linux.intel.com, tglx@linutronix.de Reply-To: mingo@kernel.org, hpa@zytor.com, eranian@google.com, linux-kernel@vger.kernel.org, acme@redhat.com, ak@linux.intel.com, tglx@linutronix.de In-Reply-To: <1393596135-4227-2-git-send-email-andi@firstfloor.org> References: <1393596135-4227-2-git-send-email-andi@firstfloor.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf mem: Clarify load-latency in documentation Git-Commit-ID: b63940970492f5f187d546e191bc2c6831491fe3 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: b63940970492f5f187d546e191bc2c6831491fe3 Gitweb: http://git.kernel.org/tip/b63940970492f5f187d546e191bc2c6831491fe3 Author: Andi Kleen AuthorDate: Fri, 28 Feb 2014 06:02:14 -0800 Committer: Arnaldo Carvalho de Melo CommitDate: Fri, 14 Mar 2014 11:20:44 -0300 perf mem: Clarify load-latency in documentation Clarify in the documentation that 'perf mem report' reports use-latency, not load/store-latency on Intel systems. This often causes confusion with users. Signed-off-by: Andi Kleen Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1393596135-4227-2-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-mem.txt | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/perf/Documentation/perf-mem.txt b/tools/perf/Documentation/perf-mem.txt index 888d511..1d78a40 100644 --- a/tools/perf/Documentation/perf-mem.txt +++ b/tools/perf/Documentation/perf-mem.txt @@ -18,6 +18,10 @@ from it, into perf.data. Perf record options are accepted and are passed through "perf mem -t report" displays the result. It invokes perf report with the right set of options to display a memory access profile. +Note that on Intel systems the memory latency reported is the use-latency, +not the pure load (or store latency). Use latency includes any pipeline +queueing delays in addition to the memory subsystem latency. + OPTIONS ------- ...::