From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.7 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id A1A8C7D90D for ; Wed, 13 Nov 2019 03:45:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727555AbfKMDpV (ORCPT ); Tue, 12 Nov 2019 22:45:21 -0500 Received: from out30-43.freemail.mail.aliyun.com ([115.124.30.43]:59381 "EHLO out30-43.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727466AbfKMDpV (ORCPT ); Tue, 12 Nov 2019 22:45:21 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R531e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01451;MF=yun.wang@linux.alibaba.com;NM=1;PH=DS;RN=16;SR=0;TI=SMTPD_---0ThxeNA8_1573616715; Received: from testdeMacBook-Pro.local(mailfrom:yun.wang@linux.alibaba.com fp:SMTPD_---0ThxeNA8_1573616715) by smtp.aliyun-inc.com(127.0.0.1); Wed, 13 Nov 2019 11:45:16 +0800 Subject: [PATCH 2/3] sched/numa: expose per-task pages-migration-failure From: =?UTF-8?B?546L6LSH?= To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Luis Chamberlain , Kees Cook , Iurii Zaikin , =?UTF-8?Q?Michal_Koutn=c3=bd?= , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, "Paul E. McKenney" References: <743eecad-9556-a241-546b-c8a66339840e@linux.alibaba.com> Message-ID: <16f702e2-d844-20d5-4b4d-4a18c8ffd175@linux.alibaba.com> Date: Wed, 13 Nov 2019 11:45:15 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <743eecad-9556-a241-546b-c8a66339840e@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org NUMA balancing will try to migrate pages between nodes, which could caused by memory policy or numa group aggregation, while the page migration could failed too for eg when the target node run out of memory. Since this is critical to the performance, admin should know how serious the problem is, and take actions before it causing too much performance damage, thus this patch expose the counter as 'migfailed' in '/proc/PID/sched'. Cc: Peter Zijlstra Cc: Michal Koutný Suggested-by: Mel Gorman Signed-off-by: Michael Wang --- kernel/sched/debug.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index f7e4579e746c..73c4809c8f37 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -848,6 +848,7 @@ static void sched_show_numa(struct task_struct *p, struct seq_file *m) P(total_numa_faults); SEQ_printf(m, "current_node=%d, numa_group_id=%d\n", task_node(p), task_numa_group_id(p)); + SEQ_printf(m, "migfailed=%lu\n", p->numa_faults_locality[2]); show_numa_stats(p, m); mpol_put(pol); #endif -- 2.14.4.44.g2045bb6