From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755400Ab3HLCAL (ORCPT ); Sun, 11 Aug 2013 22:00:11 -0400 Received: from mail-ve0-f172.google.com ([209.85.128.172]:41367 "EHLO mail-ve0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755312Ab3HLCAH (ORCPT ); Sun, 11 Aug 2013 22:00:07 -0400 Message-ID: <5208419E.2000605@opersys.com> Date: Sun, 11 Aug 2013 22:59:58 -0300 From: Karim Yaghmour User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130804 Thunderbird/17.0.8 MIME-Version: 1.0 To: Andi Kleen CC: linux-kernel@vger.kernel.org, Steven Rostedt , mingo@elte.hu Subject: Re: Reading perf counters at ftrace trace boundaries References: <5208263D.2080205@opersys.com> <87haevog75.fsf@tassilo.jf.intel.com> <52083CB4.2030308@opersys.com> <20130812014748.GP19750@two.firstfloor.org> In-Reply-To: <20130812014748.GP19750@two.firstfloor.org> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13-08-11 10:47 PM, Andi Kleen wrote: > That's what normal sampling already does. > > If you're worried about systematic shadow effects just randomize a bit. That's actually the point. I'd like to be able to study/compare both approaches. I could be completely off, but I'd like to see if a divide and conquer approach (i.e. based on ftrace) wouldn't take the guesswork out of smart randomization. Just a hunch. -- Karim Yaghmour CEO - Opersys inc. / www.opersys.com http://twitter.com/karimyaghmour