From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752660Ab3GAGIA (ORCPT ); Mon, 1 Jul 2013 02:08:00 -0400 Received: from moutng.kundenserver.de ([212.227.17.8]:50047 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752060Ab3GAGH7 (ORCPT ); Mon, 1 Jul 2013 02:07:59 -0400 Message-ID: <1372658875.7678.17.camel@marge.simpson.net> Subject: Re: sched: context tracking demolishes pipe-test From: Mike Galbraith To: Peter Zijlstra Cc: LKML , Ingo Molnar Date: Mon, 01 Jul 2013 08:07:55 +0200 In-Reply-To: <20130630212940.GK6626@twins.programming.kicks-ass.net> References: <1372579056.6607.16.camel@marge.simpson.net> <20130630212940.GK6626@twins.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-Provags-ID: V02:K0:TCK99t9c1bnuNYn/bFScxTF0TJWF5bP05eTMcluD/Uc M1qahSnkVboeeA5OaB9Ex5FlCJcMuZGj811L4xntTZyUs7EZuz o+qpPB40a5ZQstKWDklfMIKpLJklaaxfkP7DgHgynvh13dnvXG DuWy9ealDRd4PxFVbN5WsJxZg9KhzT0S6oYDM5SgLbxNJC/1yT 1TzVqeRtWzKzewZlwxCShqWD94glicdXMVJkXpPC6QfMO9w9+K MJkpBeTART+IUgf6Q4xnuwkhu3/JEyGj75FDAhSZIimso2WK80 YgE7zEcn2zDZR3WYRO9r6d9m4RZz1pSYlbrkVwHwUr4Riykt0a HYjxuJ5TnRnU4FNk37M3J0PwqgFkNe7iSY8sFAFH5EBemmBq9W mOgfulY7yqNWA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2013-06-30 at 23:29 +0200, Peter Zijlstra wrote: > Yeah, who'd have thought that putting stuff in the syscall path would've > made syscalls more expensive ;-) (careful, you'll injure my innocence, Santa and the Tooth Fairy exist!) > But yeah, that's a _lot_ more expensive.. I'd not be surprised if more > people would find that objectionable. Distros may want some hot patching or _something_ before doing the usual new=turn-it-on thing. Per trusty (spelled with 'c') old Q6600, the cost is pretty darn high. -regress is my ~light regression testing config, carried forward from 3.6.32...master across all intervening trees. -regressx is plus CONFIG_RCU_USER_QS=y CONFIG_CONTEXT_TRACKING_FORCE=y -regressxx is plus full dynticks taskset -c 3 pipe-test 1 2.6.32-regress 654.5 Khz 1.000 3.10.0-regress 652.1 Khz .996 1.000 3.10.0-regressx 476.8 Khz .728 .731 3.10.0-regressxx 275.6 Khz .421 .422 tbench 2.6.32-regress 327.502 MB/sec 1.000 3.10.0-regress 319.621 MB/sec .975 1.000 3.10.0-regressx 292.894 MB/sec .894 .916 3.10.0-regressxx 243.738 MB/sec .744 .762 netperf TCP_RR 2.6.32-regress 104041.84 Trans/sec 1.000 3.10.0-regress 94961.34 Trans/sec .912 1.000 3.10.0-regressx 82383.33 Trans/sec .791 .867 3.10.0-regressxx 61527.59 Trans/sec .591 .647