From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753301Ab1J3W30 (ORCPT ); Sun, 30 Oct 2011 18:29:26 -0400 Received: from smtprelay0230.b.hostedemail.com ([64.98.42.230]:37619 "EHLO smtprelay.b.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753021Ab1J3W3Z (ORCPT ); Sun, 30 Oct 2011 18:29:25 -0400 X-Panda: scanned! X-Session-Marker: 742E617274656D406C79636F732E636F6D X-Filterd-Recvd-Size: 1767 Date: Sun, 30 Oct 2011 22:29:23 +0000 (GMT) From: "Artem S. Tashkinov" To: arjan@infradead.org Cc: linux-kernel@vger.kernel.org Message-ID: <1179048211.51348.1320013764432.JavaMail.mail@webmail17> References: <269467866.49093.1320004632156.JavaMail.mail@webmail17> <20111030151256.27b2b20e@infradead.org> Subject: Re: Re: HT (Hyper Threading) aware process scheduling doesn't work as it should MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Mailer: Webmail X-Originating-IP: [46.147.51.36] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Oct 31, 2011, Arjan van de Ven wrote: > > On Sun, 30 Oct 2011 19:57:12 +0000 (GMT) > "Artem S. Tashkinov" wrote: > > > Hello, > > > > It's known that if you want to reach maximum performance on HT > > enabled Intel CPUs you should distribute the load evenly between > > physical cores, and when you have loaded all of them you should then > > load the remaining virtual cores. > > this is a bold statement, and patently false if you have to threads of > one process that heavily share data between eachother... > (but true for more independent workloads) In my initial message I was talking about completely unrelated tasks/ processes which share no data/instructions/whatever else. You don't need to trust my test case as you can carry out this test on your own. I have asked quite a lot of people to do that and a lot of them see this unfortunate pattern.