Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755071AbaLHKZl (ORCPT ); Mon, 8 Dec 2014 05:25:41 -0500 Received: from mail-wi0-f174.google.com ([209.85.212.174]:58333 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755040AbaLHKZi (ORCPT ); Mon, 8 Dec 2014 05:25:38 -0500 Date: Mon, 8 Dec 2014 11:25:33 +0100 From: Ingo Molnar To: Rabin Vincent , Arnaldo Carvalho de Melo Cc: Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, rabin@rab.in, Rabin Vincent Subject: Re: [PATCH 3/3] perf: bench: fix memcpy/memset output Message-ID: <20141208102533.GB19134@gmail.com> References: <1417535441-3965-1-git-send-email-rabin.vincent@axis.com> <1417535441-3965-3-git-send-email-rabin.vincent@axis.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1417535441-3965-3-git-send-email-rabin.vincent@axis.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Rabin Vincent wrote: > The memcpy and memset benchmarks return bogus results when iterations > > 0 because the iterations value is not taken into account when > calculating the final result: > > $ perf bench mem memset --only-prefault --length 1GB --iterations 1 > # Running 'mem/memset' benchmark: > # Copying 1GB Bytes ... > > 20.798669 GB/Sec (with prefault) > $ perf bench mem memset --only-prefault --length 1GB --iterations 10 > # Running 'mem/memset' benchmark: > # Copying 1GB Bytes ... > > 2.086576 GB/Sec (with prefault) > $ perf bench mem memset --only-prefault --length 1GB --iterations 100 > # Running 'mem/memset' benchmark: > # Copying 1GB Bytes ... > > 212.840917 MB/Sec (with prefault) > > Fix this. > > Signed-off-by: Rabin Vincent Acked-by: Ingo Molnar Thanks, Ingo -- 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/