From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755546AbaGQIk0 (ORCPT ); Thu, 17 Jul 2014 04:40:26 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:41982 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755030AbaGQIkX (ORCPT ); Thu, 17 Jul 2014 04:40:23 -0400 Date: Thu, 17 Jul 2014 10:40:11 +0200 From: Peter Zijlstra To: Namhyung Kim Cc: Arnaldo Carvalho de Melo , Ingo Molnar , Paul Mackerras , Namhyung Kim , LKML , Jiri Olsa , Minchan Kim Subject: Re: [PATCH] perf stat: Pass PERF_STAT_RUN environment variable for each run Message-ID: <20140717084011.GG19379@twins.programming.kicks-ass.net> References: <1405585266-28268-1-git-send-email-namhyung@kernel.org> <20140717082613.GF19379@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="MyoNyhmGqzMI/8rd" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --MyoNyhmGqzMI/8rd Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jul 17, 2014 at 05:31:14PM +0900, Namhyung Kim wrote: > Hi Peter, >=20 > On Thu, Jul 17, 2014 at 5:26 PM, Peter Zijlstra wr= ote: > > On Thu, Jul 17, 2014 at 05:21:06PM +0900, Namhyung Kim wrote: > >> When perf stat runs multiple times via -r option, it's sometimes > >> useful for a workload to know which run it executing. So pass new > >> PERF_STAT_RUN environment variable to the workload for each run > >> (starting from 1). > > > > This seems counter intuitive, runs should be _identical_ otherwise > > there's no point. That means the workload should very much _not_ know > > these things. >=20 > But I think it can be useful if a workload wants to save logfiles > based on the iteration number for example. If it doesn't want, it can > just ignore. :) That's the wrong way around. Also, there's --pre and --post hooks to preserve logfiles if you really have to do that kind of thing. --MyoNyhmGqzMI/8rd Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTx4vrAAoJEHZH4aRLwOS6AUUP/0SuqzaaQaS5MC+Ewwuu2SCr yQjzZHRYVVSfghzGyQjlYhluDcMI0d4RTB+jmrMwR3sQsX6+0LjSlNjlSSt60g4+ ois2IDZzaFs86yA3OPl6V4M3zwu0of86kaVaJBvQAaJnDKp98dfciz1WFnGkbLab jBIvCxtDNHYxX0JouhobPuKxmIlxBkWSHJzdLQ+cHIozfopNtEaTtkWdPw9+NuIk vty2fhtbjLHEhrjTplWaScxg5GupAOMtbUeU/vMOjS7obNuOldfOU9Aitaw3+4Nl IE0xdME9TXcOPjDkH7MfnlaeV598WkMHgf31hr1kLVkgyJVWtmv4ZBXa6V8z4bnL jh2YPDm2uxcIW/8WwWICSfIcIfMKmYiUJhQ8mWcWIVaZCwNy0MhGMeJhuOTwxMYY HqwZNrEWcCbwxDXAq4tdB3fg4F0whxHr61tze60dJzRTQibWV8M/Q9ngQLwdeWOk CxzuoMnfL0kKw6uizhZStO2qjImVg84oi6/e/jPpw0E1raom3AouzwH1gcGAR+Cu hp8DCXtUcJcn9CXC/pjxU371qnxzo1R4Tj9Otk8hc7QrdAGvX8mWqq4hDDP1Sy4A k8YhMUrajCkKDAbqGFUzORj7zdNhbXNDlud7gn+l0TNUrzymQGczGpe0GSSjuHkf Le9fIdlQuXMUsiOVVFgj =svHK -----END PGP SIGNATURE----- --MyoNyhmGqzMI/8rd--