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=-9.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 C647FC4727C for ; Wed, 30 Sep 2020 18:20:15 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 17D7A20738 for ; Wed, 30 Sep 2020 18:20:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="EeyePEhh" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17D7A20738 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 43DF58E0001; Wed, 30 Sep 2020 14:20:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3C6166B0062; Wed, 30 Sep 2020 14:20:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 28D728E0001; Wed, 30 Sep 2020 14:20:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0232.hostedemail.com [216.40.44.232]) by kanga.kvack.org (Postfix) with ESMTP id 0EAB36B005C for ; Wed, 30 Sep 2020 14:20:14 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id C0A87181AE864 for ; Wed, 30 Sep 2020 18:20:13 +0000 (UTC) X-FDA: 77320542306.26.rake46_45006ce27195 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin26.hostedemail.com (Postfix) with ESMTP id 9D3CF1804A300 for ; Wed, 30 Sep 2020 18:20:13 +0000 (UTC) X-HE-Tag: rake46_45006ce27195 X-Filterd-Recvd-Size: 5558 Received: from userp2120.oracle.com (userp2120.oracle.com [156.151.31.85]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Wed, 30 Sep 2020 18:20:12 +0000 (UTC) Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 08UIJ6PH035322; Wed, 30 Sep 2020 18:20:10 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=B+fcGQBdGNaLebwUov6nFzUiAkCZlQZJuaanr/Jxh98=; b=EeyePEhhSTSfBtRQw9dO0B3vVM/b5ZY0HACHFXcXNy5po7u0XstyMM9FegqupIm1IoRR R0ibTxVOXsxS3OV4YoJrfuLVadY7atz6tUyDmRRZgVW3gxteOQXOXnTbHxtIkdicY1p7 oXnyGpOp5lSGhThMhEhZw6rxUZWGpJaTiefll89qk0u/dwrURRi4MdObnC0nW0tf9UEl eCTrJI16qUTx2BBOukjJbYwrL5yE61tDvCHBQCLyKBqMp44wMGlZ7yKvrRCy3kw86Ve3 0IZw4W0JDso7P188T0gJHnUBiFeaxwNXN3yCOYJkh3cwEN9UR8UAq0dSXCwKxzutVZ8+ 5A== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 33sx9na0pn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 30 Sep 2020 18:20:10 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 08UIEtil141719; Wed, 30 Sep 2020 18:20:09 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3030.oracle.com with ESMTP id 33uv2fs0m4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 30 Sep 2020 18:20:09 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 08UIK69q032421; Wed, 30 Sep 2020 18:20:07 GMT Received: from [192.168.2.112] (/50.38.35.18) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 30 Sep 2020 11:20:06 -0700 Subject: Re: [v5] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged To: Vijay Balakrishna , Andrew Morton , "Kirill A. Shutemov" , Oleg Nesterov , Song Liu , Andrea Arcangeli , Pavel Tatashin , Michal Hocko , Allen Pais Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <1601398153-5517-1-git-send-email-vijayb@linux.microsoft.com> From: Mike Kravetz Message-ID: <2a380b84-4fee-fa4e-e862-8a8577961088@oracle.com> Date: Wed, 30 Sep 2020 11:20:05 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <1601398153-5517-1-git-send-email-vijayb@linux.microsoft.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9760 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 spamscore=0 adultscore=0 suspectscore=2 malwarescore=0 bulkscore=0 mlxlogscore=999 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009300145 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9760 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 suspectscore=2 phishscore=0 mlxscore=0 lowpriorityscore=0 adultscore=0 clxscore=1011 spamscore=0 impostorscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009300146 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 9/29/20 9:49 AM, Vijay Balakrishna wrote: > When memory is hotplug added or removed the min_free_kbytes should be > recalculated based on what is expected by khugepaged. Currently > after hotplug, min_free_kbytes will be set to a lower default and higher > default set when THP enabled is lost. This change restores min_free_kbytes > as expected for THP consumers. > > Fixes: f000565adb77 ("thp: set recommended min free kbytes") > > Signed-off-by: Vijay Balakrishna > Cc: stable@vger.kernel.org > Reviewed-by: Pavel Tatashin > Acked-by: Michal Hocko Sorry for jumping in so late. Should we use this as an opportunity to also fix up the messages logged when (re)calculating mfk? They are wrong and could be quite confusing. For example consider the following sequence of operations and corresponding log messages produced. Freshly booted VM with 2 nodes and 8GB memory: # cat /proc/sys/vm/min_free_kbytes 90112 # echo 90000 > /proc/sys/vm/min_free_kbytes # cat /proc/sys/vm/min_free_kbytes 90000 # echo 0 > /sys/devices/system/node/node1/memory56/online [ 135.099947] Offlined Pages 32768 [ 135.102362] min_free_kbytes is not updated to 11241 because user defined value 90000 is preferred [ 135.109070] khugepaged: raising min_free_kbytes from 90000 to 90112 to help t ransparent hugepage allocations # cat /proc/sys/vm/min_free_kbytes 90112 # echo 1 > /sys/devices/system/node/node1/memory56/online [ 231.656075] min_free_kbytes is not updated to 11334 because user defined value 90000 is preferred # cat /proc/sys/vm/min_free_kbytes 90112 -- Mike Kravetz