From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752452AbaHAH30 (ORCPT ); Fri, 1 Aug 2014 03:29:26 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:33417 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750844AbaHAH3Z (ORCPT ); Fri, 1 Aug 2014 03:29:25 -0400 Date: Fri, 1 Aug 2014 09:29:11 +0200 From: Peter Zijlstra To: Aaron Lu Cc: Rik van Riel , LKML , lkp@01.org, jhladky@redhat.com, Fengguang Wu Subject: Re: [LKP] [sched/numa] a43455a1d57: +94.1% proc-vmstat.numa_hint_faults_local Message-ID: <20140801072911.GE19379@twins.programming.kicks-ass.net> References: <53d70ee6.JsUEmW5dWsv8dev+%fengguang.wu@intel.com> <53D72FF5.90908@intel.com> <20140729023940.37b6aebc@annuminas.surriel.com> <20140731104241.GA9918@twins.programming.kicks-ass.net> <20140801020330.GA30211@aaronlu.sh.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="W85UVRsRRZs47q06" Content-Disposition: inline In-Reply-To: <20140801020330.GA30211@aaronlu.sh.intel.com> 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 --W85UVRsRRZs47q06 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Aug 01, 2014 at 10:03:30AM +0800, Aaron Lu wrote: > > > > ebe06187bf2aec1 a43455a1d572daf7b730fe12e =20 > > > > --------------- ------------------------- =20 > > > > 94500 ~ 3% +115.6% 203711 ~ 6% ivb42/hackbench/50%-thr= eads-pipe > > > > 67745 ~ 4% +64.1% 111174 ~ 5% lkp-snb01/hackbench/50%= -threads-socket > > > > 162245 ~ 3% +94.1% 314885 ~ 6% TOTAL proc-vmstat.numa_= hint_faults_local > It means, for commit ebe06187bf2aec1, the number for > num_hint_local_faults is 94500 for ivb42 machine and 67745 for lkp-snb01 > machine. The 3%, 4% following that number means the deviation of the > different runs to their average(we usually run it multiple times to > phase out possible sharp values). We should probably remove that > percentage, as they cause confusion if no detailed explanation and may > not mean much to the commit author and others(if the deviation is big > enough, we should simply drop that result). Nah, variance is good, but the typical symbol would be +- or the fancy =B1. ~ when used as a unary op means 'approx' or 'about' or 'same order' ~ when used as a binary op means equivalence, a weaker equal, often in the vein of the unary op meaning. Also see: http://en.wikipedia.org/wiki/Tilde#Mathematics So while I think having a measure of variance is good, I think you picked entirely the wrong symbol. --W85UVRsRRZs47q06 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJT20HHAAoJEHZH4aRLwOS6hKMP/2oFFmie5jDztW4KL36hsS7x KMz06Hxf70McAhTOtmfbX2O41J/A56h/A6r1H1GQTMdPq0IKIrYwDjMPcWSvn0Wb p+0dqq7VFmOD2dqb5br4QxSYYS11Ckd1kzmUsCGFglEnil6lPhtLxjzqxBzmYRC2 8wHjfUajQR5/SSmMTrOJtwWebY596zxI5SpKjyJNVWJ1ryfJcH2QXvurzVbxUoqL rBMBUgK3OYxdQADtVXxXUnzhZ+WVemQlteMu6rLLkkPQ3t7dItI48B9qLob+dAzc /yPCbSOffxW69q963Ilr5L3niusveYPBxBfKYiAXwUeW7iUICLftbi/2sXWHq0fJ L45pnphjTWiN9d44J8JMOJPKcoZhl2Jr+Y6v9Gar9sQDHvCfIwn/E+FOY0zDBRzo jRX0P3ekSmCkhHHwfrGYj0KT5E60PTWrc3nX1GJTIK3xjNMS9/ycMSkjFuQ6hVRT aD25H5WCFnmXWzzOTVSz3vkHeaZ/f+q5JR5TxFb3Tmodh9C1M/FcZU5NBS6lUlwm n+etuYVY+bT5b/HqVa9CsHq93+e/eQDG9iEkxSUSAD9E5bQZjWIVRFBwdUN0mRCf zyElluJ/6c54acIhkhHQR/YEfguqS1yrXzBVF1jsgunMzydBQFZ3Zm5WiZkUDIlT pcSmVq0VdLH0MBEOgdtS =5ku1 -----END PGP SIGNATURE----- --W85UVRsRRZs47q06--