From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756729Ab3JGTHf (ORCPT ); Mon, 7 Oct 2013 15:07:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51723 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756491Ab3JGTHc (ORCPT ); Mon, 7 Oct 2013 15:07:32 -0400 Message-ID: <52530665.5060805@redhat.com> Date: Mon, 07 Oct 2013 15:07:17 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Mel Gorman CC: Peter Zijlstra , Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML Subject: Re: [PATCH 39/63] sched: numa: Use a system-wide search to find swap/migration candidates References: <1381141781-10992-1-git-send-email-mgorman@suse.de> <1381141781-10992-40-git-send-email-mgorman@suse.de> In-Reply-To: <1381141781-10992-40-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/07/2013 06:29 AM, Mel Gorman wrote: > This patch implements a system-wide search for swap/migration candidates > based on total NUMA hinting faults. It has a balance limit, however it > doesn't properly consider total node balance. > > In the old scheme a task selected a preferred node based on the highest > number of private faults recorded on the node. In this scheme, the preferred > node is based on the total number of faults. If the preferred node for a > task changes then task_numa_migrate will search the whole system looking > for tasks to swap with that would improve both the overall compute > balance and minimise the expected number of remote NUMA hinting faults. > > Not there is no guarantee that the node the source task is placed > on by task_numa_migrate() has any relationship to the newly selected > task->numa_preferred_nid due to compute overloading. > > [riel@redhat.com: Do not swap with tasks that cannot run on source cpu] > Signed-off-by: Peter Zijlstra > Signed-off-by: Mel Gorman Reviewed-by: Rik van Riel -- All rights reversed From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f41.google.com (mail-pb0-f41.google.com [209.85.160.41]) by kanga.kvack.org (Postfix) with ESMTP id DA5266B0037 for ; Mon, 7 Oct 2013 15:07:29 -0400 (EDT) Received: by mail-pb0-f41.google.com with SMTP id rp2so7557177pbb.0 for ; Mon, 07 Oct 2013 12:07:29 -0700 (PDT) Message-ID: <52530665.5060805@redhat.com> Date: Mon, 07 Oct 2013 15:07:17 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH 39/63] sched: numa: Use a system-wide search to find swap/migration candidates References: <1381141781-10992-1-git-send-email-mgorman@suse.de> <1381141781-10992-40-git-send-email-mgorman@suse.de> In-Reply-To: <1381141781-10992-40-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Peter Zijlstra , Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML On 10/07/2013 06:29 AM, Mel Gorman wrote: > This patch implements a system-wide search for swap/migration candidates > based on total NUMA hinting faults. It has a balance limit, however it > doesn't properly consider total node balance. > > In the old scheme a task selected a preferred node based on the highest > number of private faults recorded on the node. In this scheme, the preferred > node is based on the total number of faults. If the preferred node for a > task changes then task_numa_migrate will search the whole system looking > for tasks to swap with that would improve both the overall compute > balance and minimise the expected number of remote NUMA hinting faults. > > Not there is no guarantee that the node the source task is placed > on by task_numa_migrate() has any relationship to the newly selected > task->numa_preferred_nid due to compute overloading. > > [riel@redhat.com: Do not swap with tasks that cannot run on source cpu] > Signed-off-by: Peter Zijlstra > Signed-off-by: Mel Gorman Reviewed-by: Rik van Riel -- All rights reversed -- 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