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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 66DC3C43381 for ; Tue, 12 Mar 2019 00:10:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22E5C2084F for ; Tue, 12 Mar 2019 00:10:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="k5MFHvIs"; dkim=pass (1024-bit key) header.d=fb.onmicrosoft.com header.i=@fb.onmicrosoft.com header.b="B4ePKuIK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726496AbfCLAJ7 (ORCPT ); Mon, 11 Mar 2019 20:09:59 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:53266 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725989AbfCLAJ6 (ORCPT ); Mon, 11 Mar 2019 20:09:58 -0400 Received: from pps.filterd (m0001255.ppops.net [127.0.0.1]) by mx0b-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x2C03GqP017275; Mon, 11 Mar 2019 17:09:37 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=facebook; bh=b7Pd1HiFaq8Q8LerO3yocf42b947cTLoE6rdxENJUnM=; b=k5MFHvIsXJPRsrUbcb47Agd0Tay/yDPLXojd5SvapSLwa3yGgALweMFalC2BunIqsNmN G1JAxxu3C8/Dsmz2IAQlV0kWvJsPx78vTD/A1FtMHViPra6ju8dKAqXVjM+3HVqvsBXp bu++xA33s0WE0yWMQ3/stxV0FvcUWvMsv+Y= Received: from maileast.thefacebook.com ([199.201.65.23]) by mx0b-00082601.pphosted.com with ESMTP id 2r5yvg0e4r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Mon, 11 Mar 2019 17:09:35 -0700 Received: from frc-mbx01.TheFacebook.com (2620:10d:c0a1:f82::25) by frc-hub02.TheFacebook.com (2620:10d:c021:18::172) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.1.1713.5; Mon, 11 Mar 2019 17:09:33 -0700 Received: from frc-hub04.TheFacebook.com (2620:10d:c021:18::174) by frc-mbx01.TheFacebook.com (2620:10d:c0a1:f82::25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.1.1713.5; Mon, 11 Mar 2019 17:09:33 -0700 Received: from NAM03-CO1-obe.outbound.protection.outlook.com (192.168.183.28) by o365-in.thefacebook.com (192.168.177.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.1.1713.5 via Frontend Transport; Mon, 11 Mar 2019 17:09:33 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.onmicrosoft.com; s=selector1-fb-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=b7Pd1HiFaq8Q8LerO3yocf42b947cTLoE6rdxENJUnM=; b=B4ePKuIKrUBLGS+T8FazeXSRUlrvmp2OKmvaPly2N4CLXHso50gjpZaJyaqYq1iJ26nRyuvr0aAhaYgsqyY7MdplmzsEsBKOaomNJGDKT5YMZb+NalFjzP8heb8n4+JeWTvoYov6Pohl9qLh49NNxSio40c8lnhseU9BeFLfXKM= Received: from BYAPR15MB2631.namprd15.prod.outlook.com (20.179.156.24) by BYAPR15MB2597.namprd15.prod.outlook.com (20.179.155.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1686.18; Tue, 12 Mar 2019 00:09:31 +0000 Received: from BYAPR15MB2631.namprd15.prod.outlook.com ([fe80::790e:7294:b086:9ded]) by BYAPR15MB2631.namprd15.prod.outlook.com ([fe80::790e:7294:b086:9ded%2]) with mapi id 15.20.1686.021; Tue, 12 Mar 2019 00:09:31 +0000 From: Roman Gushchin To: "Tobin C. Harding" CC: Andrew Morton , Christopher Lameter , Pekka Enberg , Matthew Wilcox , Tycho Andersen , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [RFC 00/15] mm: Implement Slab Movable Objects (SMO) Thread-Topic: [RFC 00/15] mm: Implement Slab Movable Objects (SMO) Thread-Index: AQHU1WWWNeCS+/ChkEynjyh1uhCoA6YHJOwA Date: Tue, 12 Mar 2019 00:09:31 +0000 Message-ID: <20190312000928.GA25059@tower.DHCP.thefacebook.com> References: <20190308041426.16654-1-tobin@kernel.org> In-Reply-To: <20190308041426.16654-1-tobin@kernel.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: BYAPR01CA0001.prod.exchangelabs.com (2603:10b6:a02:80::14) To BYAPR15MB2631.namprd15.prod.outlook.com (2603:10b6:a03:152::24) x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [2620:10d:c090:200::1:b487] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: db79a75b-38eb-440b-a824-08d6a67f0000 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600127)(711020)(4605104)(2017052603328)(7153060)(7193020);SRVR:BYAPR15MB2597; x-ms-traffictypediagnostic: BYAPR15MB2597: x-ms-exchange-purlcount: 1 x-microsoft-exchange-diagnostics: 1;BYAPR15MB2597;20:V3oCi9y5DXNhGoacojprWGP6D2MN/r/PHMyfQ5UtVBKcPTVODpILIdffqFRIAmEdLtOMf+u8o+uikivTZ5F1MW8ZYcUM85Q8QNsAu5Q7pZYRoVC6ZZgatIoWWjUYcnkRetgmhIGR+xkncYw+xVqJ/g9WsE/vKZ/u58osco54qFA= x-microsoft-antispam-prvs: x-forefront-prvs: 09749A275C x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(979002)(39860400002)(376002)(396003)(136003)(366004)(346002)(189003)(199004)(6306002)(486006)(6512007)(102836004)(33656002)(476003)(99286004)(966005)(6246003)(186003)(46003)(52116002)(53936002)(386003)(9686003)(76176011)(1076003)(105586002)(11346002)(6436002)(7736002)(81166006)(446003)(5660300002)(106356001)(81156014)(305945005)(68736007)(8676002)(478600001)(8936002)(2906002)(71190400001)(71200400001)(6506007)(14454004)(25786009)(6916009)(14444005)(316002)(256004)(4326008)(6486002)(6116002)(86362001)(54906003)(97736004)(229853002)(969003)(989001)(999001)(1009001)(1019001);DIR:OUT;SFP:1102;SCL:1;SRVR:BYAPR15MB2597;H:BYAPR15MB2631.namprd15.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: fb.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: Rqv+5v6EqJxOmWC/5Xtzjw5U5Eua9CJpIeOvO6Jqc080IrTELc5vO+O4upD7ZJsVtUlLfDOcta5iJ9cEUJ7UsMK4CnLWbdit7bhn/bWEv8zNyFoRm0DdBw/s2CLs0pw9EYfWeQnsSpB1gpZNweCkSDooizPwdamD0OxYfUHa7JwnPTL6RK1cdZLzqpN8c8kvhP21I61U7gagXOYja6kmzUv3BlO9lwUcpL+I2S7iFW/a2Ztmkts4qneVW8fRarOFWLEGjiO+62ezixpaWmvE/4kEdG6oJZ9taHk2mvjCjAmBMz18c8OKM4aLxFDRXy3nA3bWJFBgwi5+NdGesgoFGizcr8iArYGDYloMI7VbD3kMTz7Gm3Tfl3PO69PuutPFjPKY94rWOr5hMVhWkjBW3XqESUfZAevkGERPGG6taO8= Content-Type: text/plain; charset="us-ascii" Content-ID: <39E60E583FE06A488ECD823CDDDD8185@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: db79a75b-38eb-440b-a824-08d6a67f0000 X-MS-Exchange-CrossTenant-originalarrivaltime: 12 Mar 2019 00:09:31.3326 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB2597 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-03-11_17:,, signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 08, 2019 at 03:14:11PM +1100, Tobin C. Harding wrote: > Hi, >=20 > Here is a patch set implementing movable objects within the SLUB > allocator. This is work based on Christopher's patch set: >=20 > https://lore.kernel.org/patchwork/project/lkml/list/?series=3D377335 >=20 > The original code logic is from that set and implemented by Christopher. > Clean up, refactoring, documentation, and additional features by myself. > Blame for any bugs remaining falls solely with myself. Patches using > Christopher's code use the Co-developed-by tag. >=20 > After movable objects are implemented a number of useful features become > possible. Some of these are implemented in this series, including: >=20 > - Cache defragmentation. =20 >=20 > Currently the SLUB allocator is susceptible to internal > fragmentation. This occurs when a large number of cached objects > are allocated and then freed in an arbitrary order. As the cache > fragments the number of pages used by the partial slabs list > increases. This wastes memory. >=20 > Patch set implements the machinery to facilitate conditional cache > defragmentation (via kmem_cache_defrag()) and unconditional > defragmentation (via kmem_cache_shrink()). Various sysfs knobs are > provided to interact with and configure this. >=20 > Patch set implements movable objects and cache defragmentation for > the XArray. >=20 > - Moving objects to and from a specific NUMA node. >=20 > - Balancing objects across all NUMA nodes. >=20 > We add a test module to facilitate playing around with movable objects > and a python test suite that uses the module. >=20 > Everything except the NUMA stuff was tested on bare metal, the NUMA > stuff was tested with Qemu NUMA emulation. >=20 > Possible further work: >=20 > 1. Implementing movable objects for the inode and dentry caches. >=20 > 2. Tying into the page migration and page defragmentation logic so that > so far unmovable pages that are in the way of creating a contiguous > block of memory will become movable. This would mean checking for > slab pages in the migration logic and calling slab to see if it can > move the page by migrating all objects. Hi Tobin! Very interesting and promising patchset! Looking forward for inode/dentry moving support, might be a big deal for allocating huge pages dynamically. Thanks!