From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 056A0C32789 for ; Mon, 5 Nov 2018 00:20:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A51452082E for ; Mon, 5 Nov 2018 00:20:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A51452082E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387473AbeKEJhE (ORCPT ); Mon, 5 Nov 2018 04:37:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39862 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387412AbeKEJhE (ORCPT ); Mon, 5 Nov 2018 04:37:04 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 920193D15; Mon, 5 Nov 2018 00:20:13 +0000 (UTC) Received: from localhost (ovpn-8-18.pek2.redhat.com [10.72.8.18]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C18756596B; Mon, 5 Nov 2018 00:20:12 +0000 (UTC) Date: Mon, 5 Nov 2018 08:20:09 +0800 From: Baoquan He To: Michal Hocko Cc: Andrew Morton , linux-mm@kvack.org, LKML , Michal Hocko , Stable tree Subject: Re: [PATCH] mm, memory_hotplug: teach has_unmovable_pages about of LRU migrateable pages Message-ID: <20181105002009.GF27491@MiWiFi-R3L-srv> References: <20181101091055.GA15166@MiWiFi-R3L-srv> <20181102155528.20358-1-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181102155528.20358-1-mhocko@kernel.org> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Mon, 05 Nov 2018 00:20:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Michal, On 11/02/18 at 04:55pm, Michal Hocko wrote: > From: Michal Hocko > > Baoquan He has noticed that 15c30bc09085 ("mm, memory_hotplug: make > has_unmovable_pages more robust") is causing memory offlining failures > on a movable node. After a further debugging it turned out that > has_unmovable_pages fails prematurely because it stumbles over off-LRU > pages. Nevertheless those pages are not on LRU because they are waiting > on the pcp LRU caches (an example of __dump_page added by a debugging > patch) > [ 560.923297] page:ffffea043f39fa80 count:1 mapcount:0 mapping:ffff880e5dce1b59 index:0x7f6eec459 > [ 560.931967] flags: 0x5fffffc0080024(uptodate|active|swapbacked) > [ 560.937867] raw: 005fffffc0080024 dead000000000100 dead000000000200 ffff880e5dce1b59 > [ 560.945606] raw: 00000007f6eec459 0000000000000000 00000001ffffffff ffff880e43ae8000 > [ 560.953323] page dumped because: hotplug > [ 560.957238] page->mem_cgroup:ffff880e43ae8000 > [ 560.961620] has_unmovable_pages: pfn:0x10fd030d, found:0x1, count:0x0 > [ 560.968127] page:ffffea043f40c340 count:2 mapcount:0 mapping:ffff880e2f2d8628 index:0x0 > [ 560.976104] flags: 0x5fffffc0000006(referenced|uptodate) > [ 560.981401] raw: 005fffffc0000006 dead000000000100 dead000000000200 ffff880e2f2d8628 > [ 560.989119] raw: 0000000000000000 0000000000000000 00000002ffffffff ffff88010a8f5000 > [ 560.996833] page dumped because: hotplug Sorry, last week I didn't test this patch with memory pressure adding. Today use "stress -m 200 -t 2h" to add pressure, hot removing failed. Will send you output log. W/o memory pressure, it sometimes succeed. I saw one failure last night, it still show un-removable as 0 in hotpluggable node one time, I worried it might be caused by my compiling mistake, so compile and try again this morning. Thanks Baoquan