Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754420Ab3IKObV (ORCPT ); Wed, 11 Sep 2013 10:31:21 -0400 Received: from a14-29.smtp-out.amazonses.com ([54.240.14.29]:34659 "EHLO a14-29.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753615Ab3IKObU (ORCPT ); Wed, 11 Sep 2013 10:31:20 -0400 X-Greylist: delayed 612 seconds by postgrey-1.27 at vger.kernel.org; Wed, 11 Sep 2013 10:31:20 EDT Date: Wed, 11 Sep 2013 14:21:06 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Mike Galbraith cc: Gilad Ben-Yossef , Andrew Morton , Thomas Gleixner , Frederic Weisbecker , Mike Frysinger , "linux-kernel@vger.kernel.org" , "Paul E. McKenney" Subject: Re: [RFC] Restrict kernel spawning of threads to a specified set of cpus. In-Reply-To: <1378869632.5476.34.camel@marge.simpson.net> Message-ID: <000001410d659f85-21128fa5-a252-4006-804c-4ff03acbd50f-000000@email.amazonses.com> References: <00000140efbcb701-c26320b3-f434-4538-bc80-8e92fed6f303-000000@email.amazonses.com> <1378795659.6046.41.camel@marge.simpson.net> <1378797995.6046.54.camel@marge.simpson.net> <0000014109b5ec0e-ca64a736-ce4a-4be2-abf6-bbf2c1c15f80-000000@email.amazonses.com> <1378869632.5476.34.camel@marge.simpson.net> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 2013.09.11-54.240.14.29 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1029 Lines: 23 On Wed, 11 Sep 2013, Mike Galbraith wrote: > Mind saying why? To me, creating properties of exclusive sets of CPUs > that the interface which manages sets and their properties is not fully > aware of is a dainbramaged thing to do. cpusets is being replaced by cgropus. And the mechanism adds some significant latencies to core memory management processing path. Also many folks in finance like to deal directly with the hardware (processor numbers, affinity masks etc). There are already numerous ways to specify these masks. Pretty well established. Digging down a cpuset hierachy is a bit tedious. Then these cpusets can also overlap which makes the whole setup difficult. If cpusets can be used on top then ok but I would like it not to be required to have that compiled in. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/