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 37251C6FD1D for ; Wed, 22 Mar 2023 01:35:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B2D066B007D; Tue, 21 Mar 2023 21:35:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id ADC826B007E; Tue, 21 Mar 2023 21:35:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 92EA1900002; Tue, 21 Mar 2023 21:35:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 7E1976B007D for ; Tue, 21 Mar 2023 21:35:20 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 439BC40337 for ; Wed, 22 Mar 2023 01:35:20 +0000 (UTC) X-FDA: 80594816400.06.EE21AC7 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf30.hostedemail.com (Postfix) with ESMTP id 9773280002 for ; Wed, 22 Mar 2023 01:35:14 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=cIQPghdD; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf30.hostedemail.com: domain of fengwei.yin@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=fengwei.yin@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1679448916; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=777O0UmJ8P9NYDVR7wee2gS8aeL8P758PqlEf4JxUzc=; b=7xXpq3FHcnKwOjWujJKuRHX1xll3ITfbqo80Qg4ITDUDZTmfzaB8rRK+dm5uFfFVDwkH2q wFblMwusQxqTRH3ygBddlmNn0xUE7zg1DtpzO+mypsza3frTpx40fniaylg0lb7Svzi0/W cLHdTkzpy7iC8aeuqWKc3g4c48U1WeA= ARC-Authentication-Results: i=2; imf30.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=cIQPghdD; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf30.hostedemail.com: domain of fengwei.yin@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=fengwei.yin@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1679448916; a=rsa-sha256; cv=fail; b=rFD//POiHhiSiovZsngKmv1kspCKaJ3+CdC4ApW3P6Qu7S+NUSakuLSbSswN07QFFeJTYE yOgEHdPMQFlvndXlqN+nE/eiIMoqhXqL+WKvcGuGwd9cg4HMN2Jxh4etc2vyaMlcbTshbq Kk2R6lmrB6wmCaZNUOKNP3JaHndvL0Q= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679448914; x=1710984914; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=3lqEgbufv+G+OR6Gjp6GL6uHn9vCMvua/O16z8Y4+O4=; b=cIQPghdDNePwVdEk5A30h4O9zRqZiDY+4beuLTaDynGGWk6+dhVlNlfc PbDMLIZu+DJpiJE1tLTDa+lMwM0HSuQ1C3VXxCyNLWf0dW0h7BrXMA9vc F3J0NvSKvdSh1HKEn7CYi7SpcxQ2CR17RCj5Nb4OZ4wxgywaTuMqILqND V6yFf8z73IgabUaBZfZf4dR8HhwqMpkSIAY5Yb7oJNpS2TxgdIFcTVW/B xHedbe8z+NyY8E+jSNvW9QmkjITFnYR/5WoOvDNkDYQxiERT/zvZ3rLa0 3JNKFB6cHre8O2+J7oBhzghMP61LYkNDJV6VlKoqVYIbQL0gMCmJhLtKU A==; X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="403988012" X-IronPort-AV: E=Sophos;i="5.98,280,1673942400"; d="scan'208";a="403988012" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Mar 2023 18:35:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="712049554" X-IronPort-AV: E=Sophos;i="5.98,280,1673942400"; d="scan'208";a="712049554" Received: from fmsmsx603.amr.corp.intel.com ([10.18.126.83]) by orsmga008.jf.intel.com with ESMTP; 21 Mar 2023 18:35:11 -0700 Received: from fmsmsx603.amr.corp.intel.com (10.18.126.83) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 21 Mar 2023 18:35:11 -0700 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21 via Frontend Transport; Tue, 21 Mar 2023 18:35:11 -0700 Received: from NAM12-BN8-obe.outbound.protection.outlook.com (104.47.55.174) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.21; Tue, 21 Mar 2023 18:35:10 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=RBSWZiuaGdO+P5xUP+sAxdTpk8QQKvFFdiUQy6fntcNsYtf+Wsu1nssvvELO7Xnjs6C8G9RPngBmeIkS2z8pIhzMKRed2a0GVz8yGf9FkhqSVSb+axrM/lqxMnlRnHua+nkkQh47bQ7xm/Zn0pSY+eDu1py4KcZpl63kHK1AiXWu30tZDPwNjBRrQdzAViLfFws604B0zitPyap63/3bJ+4RThmr1LoYaWcaqj02SIQkEpZN9TlwoJrCLN+RLQrus1Lvv5P2HvFy+C9MZ+bgtiigoQ8S1QkgZvCLiACxvaaYdh5iSl7ShIFpt5i9a7gVxyWdxgBTQ4pftUB4R35nCw== 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=777O0UmJ8P9NYDVR7wee2gS8aeL8P758PqlEf4JxUzc=; b=Zuttopy7aURDZXN3/CDV4GakPbR0auc9GK3/qobG/loi6bYa+59SI+H2v7IPSxUJpraoqwP7gtDCRwINlDLr0ym03HDPldm9HYX6YopYeL7ASELrUYtpC8tx6vDERevWsoCxOhLDcpZjzMaTiHYyG5G7dIAAalQFYNEPQpCEDET2Q/dF7VDpervzG/JwcARVgrocIeGs/t27+gz2aUOdIAihcOCgxsgo8ltN6nnyszip0Szsq6+Ju+XI3Hhdxf26JQiNTe+8tXhsKQ74Tm9hMfOnCHOHfD1qYbOEv5/NBVo3tAaIsVFYwBbpeWO+t7gHXRj0RTb+0AiqfDiJn9gZWA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Received: from CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) by SA3PR11MB8074.namprd11.prod.outlook.com (2603:10b6:806:302::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6178.37; Wed, 22 Mar 2023 01:35:08 +0000 Received: from CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::8073:f55d:5f64:7c6]) by CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::8073:f55d:5f64:7c6%8]) with mapi id 15.20.6178.037; Wed, 22 Mar 2023 01:35:08 +0000 Message-ID: Date: Wed, 22 Mar 2023 09:31:04 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v4 0/5] batched remove rmap in try_to_unmap_one() Content-Language: en-US To: David Hildenbrand , Andrew Morton CC: , , , , , References: <20230313124526.1207490-1-fengwei.yin@intel.com> <20230313114900.96cfad6c3e4b684646f74e61@linux-foundation.org> <9c6f1e65-d460-8204-4ef6-bf76d1a78b58@redhat.com> From: Yin Fengwei In-Reply-To: <9c6f1e65-d460-8204-4ef6-bf76d1a78b58@redhat.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: BN7PR02CA0001.namprd02.prod.outlook.com (2603:10b6:408:20::14) To CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PR11MB4820:EE_|SA3PR11MB8074:EE_ X-MS-Office365-Filtering-Correlation-Id: 6f99fca8-35f9-4589-0808-08db2a75ab48 X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr 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:CO1PR11MB4820.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230025)(396003)(376002)(346002)(39860400002)(136003)(366004)(451199018)(41300700001)(66946007)(36756003)(66556008)(66476007)(8676002)(4326008)(38100700002)(82960400001)(2906002)(8936002)(5660300002)(6506007)(86362001)(6512007)(26005)(31696002)(53546011)(6666004)(2616005)(6486002)(31686004)(83380400001)(110136005)(66899018)(478600001)(186003)(316002)(45980500001)(43740500002);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?L0JOMlNzUVJMMnAzWmtNd0JTR2xuREw1UUE3SEIrSnhqR0M2ZWhWSWdQSWVy?= =?utf-8?B?WEx4U3A0MUozVjNmdFdxUWFUOGFqWm5Da3dtU3J4ZEpDTmFNSXFTb1FUNkJo?= =?utf-8?B?QjVNT3JTRmpLWTdmWjR3U01oR05aZFhBeHh6V0p3aHUvMytiTXhseEwxZi9a?= =?utf-8?B?R2o3UWFya2FteldvempJVzNlbnN1MmE3QTBkTmpSUE40NEJNU2xTa2R0OUdY?= =?utf-8?B?U2ZSdGk0MUNDMU9SazErc3ltRy9KUU1sRFlTV3FUZlhTSXVFbjl3OXJqbzJV?= =?utf-8?B?RFIwR2I4T2pqWVJ3cWQwR3pOUFA0dFhiTVBBT2J3aUF0ZVFNNTMwTjlLY3ZL?= =?utf-8?B?b0JBbWZiNVVTQ04vNzdZSkFqYXlZN3M0cGFMVC9CSzh3L3h0bHkyYldNTmRP?= =?utf-8?B?UkdsYUYydjVpWDAzc1UwV3M2aGJNeDJpTG9xQ3RRRFgvejRKQS9vVnF1K1F5?= =?utf-8?B?V2hNZXdpMVpwd1BycXZIRlI2clVHSHBlbTNsUytVTW04S0htV1hSNUxleXBW?= =?utf-8?B?ZFFaTWtzT3pnU1N1SEJLZUNOUVUxUXJ3UEdybFk4YUFCbUVRWDRoMXJ3SXJH?= =?utf-8?B?N1p0eFdNVjVtWnoweWZhbEk3Sk92ZGdpaktsNG9ic0VjcEZXdlFQd2N5dlRP?= =?utf-8?B?SWF0MzVEUzZHZVRsWm5YU21uWklwRDQvbnZaWkRlMkptRmVMMXI4MjNnUWVu?= =?utf-8?B?UCtENkdaWmhJWWJ6OHRQWlJlL09TclBLY2pDZ1hscUpvbkFkRDc0NTYxelZm?= =?utf-8?B?bkJNVkZDdnlKVmg3a0RjTDJTczlYTWh6TUZ2QUhCaVBxZ09vMnU2dHRVTnhO?= =?utf-8?B?dCt3czQ1RUZmM1FLUitZZjBXTE1OK1dXelJtRjJtTWdRRUlOdVpRaDhMcHQy?= =?utf-8?B?c29QVGJ5Rldnci9ITjUvcEl6ZURtWi9Rakp3R2piUi9LaWpJdXM2Y0srdTNn?= =?utf-8?B?cFNhK1JuUzZBUkxTSW5jdjFlcXZpNklHdVYyN1JTOGI5Q2d0Y2ZsQWVod3pu?= =?utf-8?B?NGZ1K244bEg2Uk84WUsyMG92d2g3aFc4Vkxkb0w0UUhRQVZ4K0N6TmdYbVZn?= =?utf-8?B?ZU1WdHpNOTdTaG1KL005NUxBNXpxaDNzTzlDTVVydzhBOGEwd0lTM0ZYbE4x?= =?utf-8?B?d0I2aHBWdGdOR2tCMnkxKzNuNThrdllwZm1jTmR5dStraVZibjdhdEZxTzdx?= =?utf-8?B?SlBoNjBDR2hxY28zR0t4SzZTeHVHSmNKa0N1Rk9NUG1HeDVqazBtaStrZWov?= =?utf-8?B?Sml3RTdtR0lHN2pvY0I5RGtuRExnWHhJZC9rVXBYREZMQllBbTFpUjMxMUlD?= =?utf-8?B?NXZWMzRBMTAyaW00RHJZb2ZEVFBZNUhWWTYvMFRGS3o3YUExbDdMa05HdXoy?= =?utf-8?B?NzgyakpHTVgzYXp3NVZ1cndwZnhHZ3BZQ0s1NHZqNys2LysrWlh2dkNmSnJH?= =?utf-8?B?MVNIZll5NkRVN2hIamt0OG1vd3NibnhmWVRWdUY1ZDg5TTlJOFJvZFdDVFhS?= =?utf-8?B?VHFkTHp6blB2NnQ3L04wU1ZwZk5ycTlwQ0s2ZnhXbFNkR1NXWXpqeGl3UHNj?= =?utf-8?B?bURlM292MC9QdDVaZnpqcHQ5d0JFZHFwazhRVG5iM1ZRSnV6Q1YzUUxIZm9k?= =?utf-8?B?OXNCVDdpMDIxU2tXakx2SFBZbCtJMVRZUWZaYkxRYXVyVGZhWFdabDF2VCtt?= =?utf-8?B?dnBwaWRybFBaRGxTYThBZUQrR056VC9aMDJhMzJxdjg4UjJ1UE94b3BDeDB6?= =?utf-8?B?ZVJpek5KZ3ptZnhRQithS0YvMDhVYWc5a2JmKytXSkpBYkF3V0lBdjVxMnB5?= =?utf-8?B?NTdKc3NBVWM2RUZTRmVDS0xlbElWd0tyTG9hbmJacVE1d1JBdmtxUXhiYkZL?= =?utf-8?B?TG54ZmVuclB1TEN5NGxNZDJadFJUbjZMbkhhMVo4K2YvWTh5TUozVmxYWGFQ?= =?utf-8?B?WTNNQjdUdXlBR2dyZFQ0b1lrTjhhbjRQRHN0S0RzNk00ZENuL0lkUzAvR1lk?= =?utf-8?B?VWsxTktVNzg4RG1vTXU3cElNMm8zc3ZZUCt3UmdZaWZvYVlzMUtZS3l3OUpH?= =?utf-8?B?a1BGK21EWHFRQWdoWC9TV1FTV3RwLy84M2hEMzlubFFkOUxUWUpEckpka3FD?= =?utf-8?B?RXFyanNnMDlzZDAvVm5wOUZJZVc3MU1EYWRodjYrZFppQ0N6Z2VNZGMyRHA5?= =?utf-8?B?Ymc9PQ==?= X-MS-Exchange-CrossTenant-Network-Message-Id: 6f99fca8-35f9-4589-0808-08db2a75ab48 X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB4820.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Mar 2023 01:35:08.2939 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: HiiuLHUDDuV9kJHAiYYyl3UGWK2wCqAzN/lyTrnZv3+s7vVyJTDnJtlguTgDOmv4KPMMjNRnCffAwEDCmG/few== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR11MB8074 X-OriginatorOrg: intel.com X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 9773280002 X-Stat-Signature: en3yuidc45b6zsf81gx7ohiewshjjqip X-HE-Tag: 1679448914-577592 X-HE-Meta: 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 yzvU2MSv yHfYPJpA7BAca/NBUetpWCmIp0G13ImjQ66Ijbe4zkQUtymmiijdmprEfCDetb0aPutqR7JNYt45dqkrjqNr94W15RBJgY/RvPN/chxAdaMYFbwWo5crnVfrGw5sYOKZGjisiXyRCDEsZgQiHtpodg8/sr0MrnaTzPvKeNh+HsYgrtoxnxYBw6j8PWQ8IgpsAEDdjlnGNHHxgLowUoNGAXVLnNFQLKbmGHipygqrCEryBhJgnZJPWgahrixvXVzww7Zr7lqCJMcih2CsMA1izBGH3U0wX8NJil6dtu+2DnALozDSUx/tFUOgjHID57CdPPswXceLPSH2ZTv+HZSRnRtrkV6QskUu4PtIbakArbig5NxQ+nOvfVCZgGA== 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 3/21/23 22:17, David Hildenbrand wrote: > On 20.03.23 14:47, Yin, Fengwei wrote: >> Hi Andrew, David, >> >> On 3/14/2023 11:09 AM, Yin Fengwei wrote: >>> On 3/14/23 02:49, Andrew Morton wrote: >>>> On Mon, 13 Mar 2023 20:45:21 +0800 Yin Fengwei >>>> wrote: >>>> >>>>> This series is trying to bring the batched rmap removing to >>>>> try_to_unmap_one(). It's expected that the batched rmap >>>>> removing bring performance gain than remove rmap per page. >>>>> >>>>> This series reconstruct the try_to_unmap_one() from: >>>>>     loop: >>>>>        clear and update PTE >>>>>        unmap one page >>>>>        goto loop >>>>> to: >>>>>     loop: >>>>>        clear and update PTE >>>>>        goto loop >>>>>     unmap the range of folio in one call >>>>> It is one step to always map/unmap the entire folio in one call. >>>>> Which can simplify the folio mapcount handling by avoid dealing >>>>> with each page map/unmap. >>>>> >>>>> ... >>>>> >>>>> For performance gain demonstration, changed the MADV_PAGEOUT not >>>>> to split the large folio for page cache and created a micro >>>>> benchmark mainly as following: >>>> >>>> Please remind me why it's necessary to patch the kernel to actually >>>> performance test this?  And why it's proving so hard to demonstrate >>>> benefits in real-world workloads? >>>> >>>> (Yes, this was touched on in earlier discussion, but I do think these >>>> considerations should be spelled out in the [0/N] changelog). >>> OK. What about add following in cover letter: >>> " >>>   The performance gain of this series can be demonstrated with large >>>   folio reclaim. In current kernel, vmscan() path will be benefited by >>>   the changes. But there is no workload/benchmark can show the exact >>>   performance gain for vmscan() path as far as I am aware. >>> >>>   Another way to demonstrate the performance benefit is using >>>   MADV_PAGEOUT which can trigger page reclaim also. The problem is that >>>   MADV_PAGEOUT always split the large folio because it's not aware of >>>   large folio for page cache currently. To show the performance benefit, >>>   MADV_PAGEOUT is updated not to split the large folio. >>> >>>   For long term with wider adoption of large folio in kernel (like large >>>   folio for anonymous page), MADV_PAGEOUT needs be updated to handle >>>   large folio as whole to avoid splitting it always. >>> " >> I just want to check how I can move this work forward. Is it enough >> by adding above message? Or still need some other work be done first? >> Thanks. > > I think Andrew can add that, no need to resend. But we should see more > review (I'm fairly busy ...). OK. Regards Yin, Fengwei >