From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753278AbYHKNWL (ORCPT ); Mon, 11 Aug 2008 09:22:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751511AbYHKNV5 (ORCPT ); Mon, 11 Aug 2008 09:21:57 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:41443 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751498AbYHKNV5 (ORCPT ); Mon, 11 Aug 2008 09:21:57 -0400 Message-ID: <48A03C6E.60303@novell.com> Date: Mon, 11 Aug 2008 09:19:42 -0400 From: Gregory Haskins User-Agent: Thunderbird 2.0.0.16 (X11/20080720) MIME-Version: 1.0 To: Ingo Molnar CC: Mike Galbraith , LKML , Peter Zijlstra Subject: Re: [revert] mysql+oltp regression References: <1218454322.25098.24.camel@marge.simson.net> <20080811114324.GA23529@elte.hu> <48A03049.202@novell.com> <20080811124857.GD10082@elte.hu> <48A038A6.4010104@novell.com> <20080811131400.GA909@elte.hu> In-Reply-To: <20080811131400.GA909@elte.hu> X-Enigmail-Version: 0.95.6 OpenPGP: id=D8195319 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigB1F54F82D8CB421BF0ACCF15" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigB1F54F82D8CB421BF0ACCF15 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Ingo Molnar wrote: > * Gregory Haskins wrote: > > =20 >>>> Speaking of this: Another patch I submitted to you Ingo (had to do=20 >>>> with updating the load_weight inside task_setprio) seems to also=20 >>>> have this phenomenon: e.g. its technically correct but further=20 >>>> testing has revealed negative repercussions elsewhere. So please=20 >>>> ignore that patch (or revert if you already pulled in, but I don't=20 >>>> think you have). Ill try to look into this issue as well. >>>> =20 >>> ok, under which thread/subject is that? Not queued in tip/sched/*=20 >>> yet, correct? >>> =20 >>> =20 >> Here is the original thread: >> >> http://lkml.org/lkml/2008/7/3/416 >> >> I do not believe you have queued it anywhere (public anyway) yet. >> >> Note I have already invalidated 1/2, and now I am retracting 2/2 as=20 >> well. (1/2 is actually a bogus patch, 2/2 is "technically correct"=20 >> but causes ripples in the load balancer that need to be sorted out=20 >> first. >> =20 > > ok, thanks. I'm curious, what are those ripple effects? Stability or=20 > performance? > =20 Performance. I found it while working on my pi series (which fyi I=20 should have a v2 refresh for soon, probably today...i am hoping to get=20 some review feedback from you on that as well, time permitting of course = ;). Basically the behavior I was observing was that kernel builds via distcc = would cluster all the cc1 jobs on a single core. At first I thought my=20 pi-series was screwed up, but then I realized I had applied the patch=20 referenced above earlier in my development tree, and removing it allowed = pi to work fine. I found the problem with in once boot cycle with ftrace (thanks=20 Steve!). Basically newidle balancing was always returning "no=20 imbalance" even though I had 32 cc1 threads on 1 core, and 3 idle=20 cores. Clearly not correct! So I think that by adjusting the load up,=20 we throw off the hysteresis built into the load averages and cause the=20 system to incorrectly think it's balanced. TBD. -Greg > Ingo > =20 --------------enigB1F54F82D8CB421BF0ACCF15 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAkigPG4ACgkQlOSOBdgZUxnoLACfWW0tOMKYYlQatcigMjsUeYVV NsgAnR1ClfI8sGJxLs56DFHhacnNVDDh =BvLa -----END PGP SIGNATURE----- --------------enigB1F54F82D8CB421BF0ACCF15--