From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f171.google.com (mail-pd0-f171.google.com [209.85.192.171]) by kanga.kvack.org (Postfix) with ESMTP id 8ADF56B0035 for ; Tue, 19 Nov 2013 16:49:31 -0500 (EST) Received: by mail-pd0-f171.google.com with SMTP id z10so7106263pdj.16 for ; Tue, 19 Nov 2013 13:49:31 -0800 (PST) Received: from psmtp.com ([74.125.245.146]) by mx.google.com with SMTP id ob10si12517314pbb.337.2013.11.19.13.49.29 for ; Tue, 19 Nov 2013 13:49:30 -0800 (PST) From: Andi Kleen Subject: Re: [PATCH] Expose sysctls for enabling slab/file_cache interleaving References: <1384822222-28795-1-git-send-email-andi@firstfloor.org> <20131119104203.GB18872@dhcp22.suse.cz> <20131119184200.GD29695@two.firstfloor.org> <20131119191135.GA8634@dhcp22.suse.cz> <20131119201333.GD19762@tassilo.jf.intel.com> <20131119212123.GA9339@dhcp22.suse.cz> Date: Tue, 19 Nov 2013 13:49:28 -0800 In-Reply-To: <20131119212123.GA9339@dhcp22.suse.cz> (Michal Hocko's message of "Tue, 19 Nov 2013 22:21:23 +0100") Message-ID: <87y54kvz87.fsf@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Michal Hocko writes: > > Another option would be to use sysctl values for the top cpuset as a > default. But then why not just do it manually without sysctl? I want to provide an alternative to having to use cpusets to use this, that is actually usable for normal people. Also this is really a global setting in my mind. > If you create a cpuset and explicitly disable spreading then you would > be quite surprised that your process gets pages from all nodes, no? If I enable it globally using a sysctl I would be quite surprised if some cpuset can override it. That argument is equally valid :-) The user configured an inconsistent configuration, and the kernel has to make a decision somehow. In the end it is arbitary, but not having to check the cpuset here is a lot cheaper, so I prefer the "sysctl has priority" option. Could EINVAL the cpuset setting when the sysctl is set though (but it's difficult to do the other way round). -Andi -- ak@linux.intel.com -- Speaking for myself only -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org