From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758856Ab2ESKci (ORCPT ); Sat, 19 May 2012 06:32:38 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:38995 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756189Ab2ESKcg (ORCPT ); Sat, 19 May 2012 06:32:36 -0400 MIME-Version: 1.0 In-Reply-To: <4FB66756.2060302@redhat.com> References: <4FB66756.2060302@redhat.com> Date: Sat, 19 May 2012 13:32:35 +0300 X-Google-Sender-Auth: JH2ekt3pUYD76hJk-OFugG57K4o Message-ID: Subject: Re: [tip:sched/numa] sched/numa: Introduce sys_numa_{t,m}bind() From: Pekka Enberg To: Rik van Riel Cc: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, torvalds@linux-foundation.org, pjt@google.com, cl@linux.com, bharata.rao@gmail.com, akpm@linux-foundation.org, Lee.Schermerhorn@hp.com, aarcange@redhat.com, danms@us.ibm.com, suresh.b.siddha@intel.com, tglx@linutronix.de, linux-tip-commits@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 18, 2012 at 6:14 PM, Rik van Riel wrote: > I am not convinced this is the right way forward. > > While this may work well for programs written in languages > with pointers, and for virtual machines, I do not see how > eg. a JVM could provide useful hints to the kernel, because > the Java program running on top has no idea about the > memory addresses of its objects, and the Java language has > no way to hint which thread will be the predominant user > of an object. True. OTOH, while autonuma seems to be better for the JVM, numa sched is a significant improvement over current code: http://lkml.indiana.edu/hypermail/linux/kernel/1204.0/01200.html Why is that?