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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA30EC61DA4 for ; Wed, 15 Mar 2023 20:23:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 289DC6B0075; Wed, 15 Mar 2023 16:23:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 239836B0078; Wed, 15 Mar 2023 16:23:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 08C586B007B; Wed, 15 Mar 2023 16:23:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id EA1BD6B0075 for ; Wed, 15 Mar 2023 16:23:43 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id A8D1D41163 for ; Wed, 15 Mar 2023 20:23:43 +0000 (UTC) X-FDA: 80572258326.15.B84165D Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf13.hostedemail.com (Postfix) with ESMTP id 3C64E2001E for ; Wed, 15 Mar 2023 20:23:40 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=PQKkrw49; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=FgtiOKNB; spf=pass (imf13.hostedemail.com: domain of mike.kravetz@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=mike.kravetz@oracle.com; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=none) header.from=oracle.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1678911820; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=h+9w5tHZTyDBaR8+1R6/ERMRV4DRR0Nntcr8pzs4h5E=; b=HouHq6Xk11GhL38MAxwCbiS87SswPA2CtP4uxtbKycoM5PwNAz4gb3giTPcJy3rXOTq8jk O9YTnI9aIyTZx/uXbhXE0CUhMlqcmwImtzHCJOt48HHOgieAYONEQqkQknnOYPFsIKvCVt ZnYF6Sq0d/fRCkCaTdHyFn0m/AFHZRg= ARC-Authentication-Results: i=2; imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=PQKkrw49; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=FgtiOKNB; spf=pass (imf13.hostedemail.com: domain of mike.kravetz@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=mike.kravetz@oracle.com; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=none) header.from=oracle.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1678911820; a=rsa-sha256; cv=pass; b=46vVUNqklwJ8bqm9hDZSK4jBfxNuH8HQZR0EiY5sQa8DHWUypP0zYEU8tBgR+g3Z0dqVwO 1E2PKWkQILgFLm2FJAnznkwnqRnczplOiEuPFdz7bUa7mxVkrXk3lUK1Y3GGEUQins3q2y ObqpgHOgKHEZqnJfWJXVVa1d5A3Xpik= Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 32FKERPU018201; Wed, 15 Mar 2023 20:23:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : content-type : in-reply-to : mime-version; s=corp-2022-7-12; bh=h+9w5tHZTyDBaR8+1R6/ERMRV4DRR0Nntcr8pzs4h5E=; b=PQKkrw498QUqoj07tq5wYCR5Ssmac90I55ArMC9yuuZB3gs1Ufj9I3X+tS9pviOIhmm4 KJblLBZpXdUrcIpcnR1Z3g3UXwUwOfSeARkWpE9hiN0ukVtVN8i3biPsOpOGHe4ND7A3 iJWmNxWYGxTHfevllLU8NyLeSyGZLHM5MVfeVBb+J08Fn9inKUBqXeC4odU4VtgsH9dq UXgTaNrsQ4fcfIFBm3oxdtw16zZULTpMg6kLNZVY9wPg4G8Dm2cGmQwA9l9SEBznGoRD fkf2UwfUIrIgnRdcnWRq49jAGq4J6RJpjREFzk0z764kS1EehtgAbSBTDsJyXuLTr/As hQ== Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.appoci.oracle.com [147.154.18.20]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3pbmvq00fk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 15 Mar 2023 20:23:33 +0000 Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 32FKKvOw017424; Wed, 15 Mar 2023 20:23:31 GMT Received: from nam11-bn8-obe.outbound.protection.outlook.com (mail-bn8nam11lp2169.outbound.protection.outlook.com [104.47.58.169]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 3pbmyqr22c-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 15 Mar 2023 20:23:31 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=EvkLBIP/VNqR/dHRCc2YB/bxgzN2xBWmRpDAYk5JGdRMFOGWoC3m5+x/AvxXE7ElIzzRoycbOFXImc6ohrE22yOtd38bKhUvmkH5e43L4yGvYbOurlSp1fB7Dgul5IO0/RF4X9uuM7sqDTl5isygsKqw9QYr8jE0+P/OURbivQ0ubLqMvQhx3fbWXgIKIfM0qhMgIx2+9/heSY0i5oR/AlqCB2GJr53TezNKO3GxENpXkXDxOiH9wp8AaVyJCB69CE/oW+41VjzcxXXVVin010I/+0OW0Bn6MIYwB+sYP5/QOUXVEduSVN4w5/xwkabV4EbHjSrL3n7pccCFTtrwNw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=h+9w5tHZTyDBaR8+1R6/ERMRV4DRR0Nntcr8pzs4h5E=; b=cTNNOFTLTM/n9BV0cnHwhGuAJrGIAfi6V5+Ig1MhsZNJ1zueDIlJY8yjxDODa8qKYZF22R7TObCQLr99nNJyM/V1k3gZ2PnDyX4nvU5JjC8HYXcOkd09oSEYiw7F598+m82F7MLG7pZRUa+HO+LwfA4PMl4mfaS+hT/m48j1pCUJ4zvP6wOEc1fKPnw0bANHIMN3y2Kp/TYMtfNNcMZC01ai7S4SQNRHfl0tdx0kO2Mr563y5pKDXdUoD9EWD5fSJCrgc5xdl0sDPfwsNGoU/zRjdLI6eEXZenHe1YpzFiPOIPT366plK/pmmFgf0+E7pKnki+FriW9vUaAoaAOVvw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=h+9w5tHZTyDBaR8+1R6/ERMRV4DRR0Nntcr8pzs4h5E=; b=FgtiOKNBPZLLQ7DWdjM5O1nH18ThYo6Z6sf1zb8AccFECYOIK65Jb5x2AFgk/SntrUCbd4Q2IVtf3+sx6UrXhr/vp/2hdri0R0e5Vy9FJvsieHMsXcg/gJLBfxlMeWFNL45I3YVSzoWYWIUb2smcH8P+D53ZJEo6qddUeiP3jeI= Received: from BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) by DM4PR10MB6087.namprd10.prod.outlook.com (2603:10b6:8:bf::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6178.24; Wed, 15 Mar 2023 20:23:06 +0000 Received: from BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::3db5:6e11:9aca:708a]) by BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::3db5:6e11:9aca:708a%8]) with mapi id 15.20.6178.029; Wed, 15 Mar 2023 20:23:06 +0000 Date: Wed, 15 Mar 2023 13:23:03 -0700 From: Mike Kravetz To: David Hildenbrand Cc: Stefan Roesch , kernel-team@fb.com, linux-mm@kvack.org, riel@surriel.com, mhocko@suse.com, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org Subject: Re: [PATCH v4 0/3] mm: process/cgroup ksm support Message-ID: <20230315202303.GB3092@monkey> References: <20230310182851.2579138-1-shr@devkernel.io> <273a2f82-928f-5ad1-0988-1a886d169e83@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <273a2f82-928f-5ad1-0988-1a886d169e83@redhat.com> X-ClientProxiedBy: MW4PR03CA0114.namprd03.prod.outlook.com (2603:10b6:303:b7::29) To BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BY5PR10MB4196:EE_|DM4PR10MB6087:EE_ X-MS-Office365-Filtering-Correlation-Id: 095dbd7a-531d-4156-7488-08db259315f4 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BY5PR10MB4196.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230025)(7916004)(39860400002)(396003)(346002)(136003)(376002)(366004)(451199018)(44832011)(5660300002)(7416002)(83380400001)(478600001)(1076003)(53546011)(33716001)(66556008)(6666004)(26005)(6506007)(6486002)(6512007)(4326008)(38100700002)(8936002)(33656002)(8676002)(66946007)(66476007)(9686003)(6916009)(86362001)(316002)(186003)(2906002)(41300700001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?GVEmkh1C2h8FSJ+8vRRxaSbNJRIpRNhEw9KEa3WjWlB8m4mC9PuBBIi8zXlq?= =?us-ascii?Q?tRgZ8Ln825uJUIbsnJqAuMuJXgu+Ue1XBz5tGPtHYnI6+VVCxxAMf7YxyUUp?= =?us-ascii?Q?6atRk7ltItWYaAv/ar+57ImnTDD7uekyxGOkTHxY8z8McVci4tVE/3BW8tuo?= =?us-ascii?Q?t3fHzaq8WY6eoBkZf2TBv/YvqK88WtXTuOGJgo8Iws+bFeZAzzx2XDNxWHEI?= =?us-ascii?Q?PpW+eZCljx6mAEtUUDzufdkG4mO1scHj7ThostN259hbWJBYgfng6jU0+r1b?= =?us-ascii?Q?Qwoky/qTkVZz6AXhsjVZm5canPMdp9i9m3P2BWzNS9cUzuqgfyDimsfAP4jm?= =?us-ascii?Q?0lCkuCsi+1lJNgJr8YZauQk8SqemQmx0Ekl2A7yIEIcki6Y+7GkAunc73dqr?= =?us-ascii?Q?REtqRidXVRRR2UYTPFR7YJAO3gPCX9WEfiF/gTGRuF7JJHoIQl2k86pZQ8yx?= =?us-ascii?Q?kxGEipnR2YiAFWai1RPluUhiKBI1FA8WxPkoQL1O/7jpvwhYU0O+oR5uZ0cz?= =?us-ascii?Q?cYN/ZPKekfUieS2OObrc60+udIznZPOXJNXdNFsGKaf4lNWsbPGMxoYElDgU?= =?us-ascii?Q?guMsc1yCu/VRXEqa55w8qyRzYAodemC4UWo5LqA20AI8S87bfbrNXB3U51pa?= =?us-ascii?Q?haF6wcV8ox6XnFUptTVsw7umDmuGNt8b/XeORn9/aLfTfTW7BvXqMvjM+I9X?= =?us-ascii?Q?QizVgdiAhksmTsCS7BVukcxM5j/3K302YfdvGyuzuZKnNOmdBLLmiB2j2EaR?= =?us-ascii?Q?iT4X1I4n0WvBQINRCYxfYI5HfI4/YkdWGVOSCxzdDzPyfLkXt5lSdr6xo9u2?= =?us-ascii?Q?aT3NjeoFN4922wg7M9E4NywJiMHsaFerbc9NiG6M8JgutRS/X8d4pjqQwYmY?= =?us-ascii?Q?vwHhBZY/PN+fKoNOb6Nuasuef/FOqQQdxUyVgCrAiKsjxWNdYvB8bEdt5p9g?= =?us-ascii?Q?SXteqO6fkxHnRz/lBBSYUsm+zAWsus6MR6uV0bDP3szTCgFi1anljh+aoOmJ?= =?us-ascii?Q?xkMlGgtSObwrY6mDPvTj3Dp+d+LZGOg1rA+yHE9yK8RV/FblLCY7BcUEcgHK?= =?us-ascii?Q?PL9tY48u+7rwpZf5VPyZubT6BKknNUhPVD6427fRTTTCiM/lgdUhsBSvUftR?= =?us-ascii?Q?OpnVQg4ucL2bc3cps74jYwdlpMwj4IFxb6WZs8uM+pXSs/+RaVPwkERU174e?= =?us-ascii?Q?i/LwVGJ3muq6e1XLwySKKxcKy5wtSrFkzwTym3mEsi1coPZ2sdGJ+qIMluuf?= =?us-ascii?Q?7jGNTYz8rnOb7471Q6J5fKGeJKe2VkdsQPhG6jIQg0v2ntKA/j256OeSy7Ue?= =?us-ascii?Q?ccr9CCPa25/dEGFzIKiH4hFvpZLykQYaoKd/6QqzU8JsTdzo1xndK4d0LY3/?= =?us-ascii?Q?TaQ9Xkq9LKJbsieGKVe1h0pPyIywKbj96u9uiJWO0NiOhfpZLG1V7aUTJ7sU?= =?us-ascii?Q?D7aUHUJr6j9exrfM4b+KvphqHLhqYZ44haHEPYGWNKPxq2YXhvYhBC7U3+d1?= =?us-ascii?Q?Bpf+gsj1S7+jTiE2Bt7qFpx0joeNW6fIO5DOJbvnQp0WdEV2hvj8Uucpnok/?= =?us-ascii?Q?5zuli283wXmRPtRJTyqjo4Tbk0chjV9t2jqJ7h+rm2ZBNMOOnEi6GjY4kkDQ?= =?us-ascii?Q?gA=3D=3D?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: =?us-ascii?Q?e2hVkjX4Yoo/4kParCdNiu7gbT6tYDR0mRDlLrjs2/eKYPLOYMage113CXyC?= =?us-ascii?Q?TQfSbXdCTB0JuRwv1u4LVaz6ZBjwu61q+4/76phIrAPzM59C2l9lBj/hxeX3?= =?us-ascii?Q?3juwxGcOCz7PRRXA6ZMJXiIpQDJBk7WWWR6bR4utWbwaNc0bnunznpXIiYU0?= =?us-ascii?Q?xL+NRw2gfOCuqKdCvDL6+AAdsbzlnnu0SDXIsSUPmryuknbibWGLSc/S7BuG?= =?us-ascii?Q?QyTmfMy/MnUF/K4du3x7AzYM9MKv+otgh+MON3FVHXRnvvKd9RCWLlYgrm8z?= =?us-ascii?Q?UK96zebp4H0ZoHyw7j3MGESi1C4KvE5EYqlP41xBw1MqJE2M5vsNzz+6aIrB?= =?us-ascii?Q?3QzvIawR5Bp1IVJU/mu5evvE4ONGnnNn4Rwq497miuD+iFluBOyyX6xvccy8?= =?us-ascii?Q?qAO98B3VzjpEkNREfygyYM/tDdRGLKE03coy4uP6Thc3r5JdXIxn4du1urpX?= =?us-ascii?Q?qhr6a9hvt8Ytcv/HGwB7HKNtA92RRdzIbSw1PAudKVWaPnJUEeKvCm58IqZJ?= =?us-ascii?Q?waXDklYOn229e9ALumNtSgFBXPwu6tJBVQ9Hdnq0bLd9iE+VgfXhFqICWlmb?= =?us-ascii?Q?OqlunheVX9qoEjxwoqmj8ub01pVtBwY33oJy4Rk0Wb/kvX15haNLGP4HZA2S?= =?us-ascii?Q?xprbJk3fISTYrJ6famx5vCUEdbUPf9AMQ9T0C2Bssncy0DqjjFkPwU5JF71Z?= =?us-ascii?Q?7N3+V2dznfMt81wARK89Z2EQ+4uUUk5MRgFIZ/XHTvn+IV/7XWX/rA7eCpZb?= =?us-ascii?Q?Go1d3EVmXnAf1tLd7VF/Pcs3685iEeY6Sslhs/75iSRR8Xf1NEFxQZKPKLem?= =?us-ascii?Q?2eCjnUk2ZW39gKJVP5fmpyiGZyfkjUzMy1vupAVW66Zv6zCr+r7HT2JmHFw2?= =?us-ascii?Q?AOTdCFcEqw6uY1iG7SeYDzRDSKxFvNHuh5I9PfC9+WEetYKhyHNzqdaYu2ds?= =?us-ascii?Q?pmoOGWjRdpyFdbXhVWtdWt7x8wsnB+T1MWXR1VGDwHZajGMvMhSOhKQZDWct?= =?us-ascii?Q?PbK3Hi4A3Xl5CvKnw6WvDQPoig=3D=3D?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 095dbd7a-531d-4156-7488-08db259315f4 X-MS-Exchange-CrossTenant-AuthSource: BY5PR10MB4196.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Mar 2023 20:23:06.3694 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: XyeAJm8EALycg0Kv6TLDHBky0KsVgBlvkNm8mzvBqLMieerDXVM6j3+2epoNL34L8dJOYg0AXNNpi7s/E8N0Rw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR10MB6087 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-03-15_11,2023-03-15_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 spamscore=0 phishscore=0 adultscore=0 malwarescore=0 bulkscore=0 mlxlogscore=741 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2303150000 definitions=main-2303150169 X-Proofpoint-GUID: JDE-wsrLgZfHZqyfHRaMh9fb0ddxckw3 X-Proofpoint-ORIG-GUID: JDE-wsrLgZfHZqyfHRaMh9fb0ddxckw3 X-Rspamd-Queue-Id: 3C64E2001E X-Stat-Signature: 4mtbs48uy19kt7dq4qecqe8hpr8huhth X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1678911820-50287 X-HE-Meta: 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 pWp9mBgH 0EZaONu208cF4n6SC/wMDPOP6j4Ev9DkwYH43BpzIezijYQ2T77qeLAOJvv0uj/dZ4zwl2UVMZMFGkV2QP1+WTKBLckJx4tNtCyBGW3aEiHWa8s5SkCGMYlhj9gVz9aPNkhjyRraOlRyyFnmay1JhQbegN8GjEn/c+hIGkPVv7DM1dHmOLMyDMP4bLmQ38lW2sCplOpOEXnl6hKp/m7p5W4oGBE53LMp5bgEaT7JIbqVf5tWC3QFFpbaEMQD67Y6e3Dk99BCn4RtWferMexV26humgYki4AY9nnw/x42XTXVzNEo0Hh0VO4rxzNxulBep70v6allv2zwtPwzKWh50YFdH6Oa8gVQXrmmZitdz1UuFUykuXXJ2Tq78BLnq7U1jQr1Y X-Bogosity: Ham, tests=bogofilter, spamicity=0.000003, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 03/15/23 21:03, David Hildenbrand wrote: > On 10.03.23 19:28, Stefan Roesch wrote: > > Stefan, can you do me a favor and investigate which pages we end up > deduplicating -- especially if it's mostly only the zeropage and if it's > still that significant when disabling THP? > > I'm currently investigating with some engineers on playing with enabling KSM > on some selected processes (enabling it blindly on all VMAs of that process > via madvise() ). > > One thing we noticed is that such (~50 times) 20MiB processes end up saving > ~2MiB of memory per process. That made me suspicious, because it's the THP > size. > > What I think happens is that we have a 2 MiB area (stack?) and only touch a > single page. We get a whole 2 MiB THP populated. Most of that THP is zeroes. > > KSM somehow ends up splitting that THP and deduplicates all resulting > zeropages. Thus, we "save" 2 MiB. Actually, it's more like we no longer > "waste" 2 MiB. I think the processes with KSM have less (none) THP than the > processes with THP enabled, but I only took a look at a sample of the > process' smaps so far. > > I recall that there was a proposal to split underutilized THP and free up > the zeropages (IIRC Rik was involved). > > I also recall that Mike reported memory waste due to THP. Interesting! 2MB stacks were also involved in our case. That stack would first get a write fault allocating a THP. The write fault would be followed by a mprotect(PROT_NONE) of the 4K page at the bottom of the stack to create a guard page. The mprotect would result in the THP being split resulting in 510 zero filled pages. I suppose KSM could dedup those zero pages. -- Mike Kravetz