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 4C755C433F5 for ; Thu, 2 Dec 2021 17:27:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 90CD46B0072; Thu, 2 Dec 2021 12:27:41 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BC546B0074; Thu, 2 Dec 2021 12:27:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6E7686B0075; Thu, 2 Dec 2021 12:27:41 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0149.hostedemail.com [216.40.44.149]) by kanga.kvack.org (Postfix) with ESMTP id 599F56B0072 for ; Thu, 2 Dec 2021 12:27:41 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 1E50D89D3B for ; Thu, 2 Dec 2021 17:27:31 +0000 (UTC) X-FDA: 78873535902.05.131D22E Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by imf04.hostedemail.com (Postfix) with ESMTP id 939A240003 for ; Thu, 2 Dec 2021 17:27:30 +0000 (UTC) Received: from pps.filterd (m0246631.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 1B2HHa2b020441; Thu, 2 Dec 2021 17:27:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=message-id : date : subject : to : references : cc : from : in-reply-to : content-type : content-transfer-encoding : mime-version; s=corp-2021-07-09; bh=GzBpBm8OlnMNs5eemPJt8t33n+nr2gqdhKsL4FPOLvg=; b=veW0liEiihbiJlh6IS5h4O0uhmdFiMJDwNjhMucMDo2JtA9YhsLm/S51NDMLGpXp5577 QDMIiVZ3H+s0CZabNDlt6jJfYfBWDAVDoNZ2KYMX27ERyA2GeG+2AcaaLzAqeaSvHtv8 uvXEXWAa95NPJWIQvFKcgrfz9Lv7ifNmfQbL4z8qj8YSLlVYFtR8NIe4qYE4f0V5otN6 XLVQxIcfwZi2GJuXDsm6wYCThDIQhnAIfjX14SqNjjSJqij75B5RDqpmzHopCspNjqw7 XKrCszX0oLy0Rn6585pUNaqMar4z9/9yVLYpmEM6tZe4ZiN+3lLvANgdu75UynGG2gp1 6g== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by mx0b-00069f02.pphosted.com with ESMTP id 3cp9gksa6n-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 02 Dec 2021 17:27:24 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.1.2/8.16.1.2) with SMTP id 1B2HGQO2001589; Thu, 2 Dec 2021 17:27:22 GMT Received: from nam12-bn8-obe.outbound.protection.outlook.com (mail-bn8nam12lp2174.outbound.protection.outlook.com [104.47.55.174]) by userp3020.oracle.com with ESMTP id 3cke4ukg15-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 02 Dec 2021 17:27:21 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=QndwIEuHD9eDyTXAIvg6Uotx94+yQNfzwBDrzng/PZGI3LCyXTSwIwYYNYRa6favjuZyLl1Gwn+aq+bKAAqTUOnVI/44gNsb/UxpFQDX4fidctPTMEWmUfXR88B2j78COKSmpSsQSJEZj3XMJTX7OjGsCgQisejQCItJvfiiEJPMuF3booQp/x4YVlqGPOdiiuDUhMNA2c2OH4JgZAENMI8QB9BqD5u/5XgHcqh83JoUENs/g4/gHzzOa+bK9RkNkRWORODh2TVyRovutItS51P7vnG+YN/LbdtlkFjd2e/q+n5FKY42ZadvaKFpfiQTMgpsOKcviDny22ifl4LSlw== 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=GzBpBm8OlnMNs5eemPJt8t33n+nr2gqdhKsL4FPOLvg=; b=ZrAG+4GKkGalLBkvK7yocRKNsft5z3g8ypKqzYaOJ7Nrh4O+TRZPr8uqFsk/oSVGIkOuXmGvwdyhI6WmtcYygyLZIR2fiIBMH6LFn5cqO1zx4gdLsG2+lpL7s3MuloFOneJcPtxlW0cKqGX5+UsJrWAVUSB1Zk+ES/S2L07+DgH/L0fazbTJKw9F3A1ECQEZhXMpN9rlJJgmFIOu5G2d3ewQYpLGyHBBF8YTOycTUhcSoUhOD7JyomyA268YFNLMu2TVZEYAs/zWPyGCG9QV+lQIqFNMI0wmCpUdb0VfQuxnG2hChm/iXf5vri04TjmHL1YtdLucDJdqXgf55cb+dg== 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=GzBpBm8OlnMNs5eemPJt8t33n+nr2gqdhKsL4FPOLvg=; b=yX8OBDYzWmAE2LoomiVVJy8356VepBqD8CY/dEV/ygzJ4A947PEUAGh5o42p0gx2M1K4tWICNgFIezA48obgwltmBHd656WssqhfMMD03r2tkoKJ7S4dKKQ4JWOpCkh0/zjFHeF9pgwCk0kMVy83XhLLPnfM6RD4y6i59ZGIEdM= Received: from BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) by BY5PR10MB4273.namprd10.prod.outlook.com (2603:10b6:a03:205::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4734.28; Thu, 2 Dec 2021 17:27:19 +0000 Received: from BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::b5bc:c29f:1c2d:afd7]) by BY5PR10MB4196.namprd10.prod.outlook.com ([fe80::b5bc:c29f:1c2d:afd7%9]) with mapi id 15.20.4755.016; Thu, 2 Dec 2021 17:27:19 +0000 Message-ID: Date: Thu, 2 Dec 2021 09:27:17 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.0 Subject: Re: [RFD] clear virtual machine memory when virtual machine is turned off Content-Language: en-US To: David Hildenbrand , fei luo , akpm@linux-foundation.org, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org References: <673c5628-da97-83d3-028f-46219f203caf@redhat.com> Cc: Joao Martins From: Mike Kravetz In-Reply-To: <673c5628-da97-83d3-028f-46219f203caf@redhat.com> Content-Type: text/plain; charset=UTF-8 X-ClientProxiedBy: MW4PR04CA0352.namprd04.prod.outlook.com (2603:10b6:303:8a::27) To BY5PR10MB4196.namprd10.prod.outlook.com (2603:10b6:a03:20d::23) MIME-Version: 1.0 Received: from [192.168.2.123] (50.38.35.18) by MW4PR04CA0352.namprd04.prod.outlook.com (2603:10b6:303:8a::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4755.11 via Frontend Transport; Thu, 2 Dec 2021 17:27:19 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: ab3b1cbf-c9a1-4781-8fea-08d9b5b8fe68 X-MS-TrafficTypeDiagnostic: BY5PR10MB4273: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8882; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: /+t0AQpxvDZSFWQUjudVZ+a4cb5Vbnq1qj5B1tN38dZtJhi2Gtxz/vpNUiarfpVbos0S99UxrFOSDwNgZY0tNDjyUWRqDzoftvR/eC6XHPc+utkZTZJ7NX22q2ABD16ATQXgrvueHP/2FsplA0rqOFjeaPcaSPlawbvCeC3Irx6bhot544jkYuANFaFTmV3TR9YLl2iSeRNV2G8ubrxrFAnr5ipXNkEbAJKNAhNK6KQG1/3eX8Jgi6f+XNQBXaBHwHtY3n0Z60djme/2pLKTrswShy7zQrq7pJUMRfokdlBPgPwumvPCxXI8SLyB5s80XpNgRHYVUpUYO41tGBFs9B03kxSJe5crTMODpInZrYUc8JzSCFvfZZH2lK5H5+MQm/v5acp870fG3NqWhtd4ok7gizh+YC+nN0ZjcGAYp4qHatTKXqZdu7098Z4TFK/EpoHnaEJBnTjHAoS9wocdAqxi/lHABFPb/N+2ygDpL1nmE/yyZk6UphswPQlUODHJhu+D8N1neAHJjqr4o/9Z1LpOCx1nLmEwCjAWNfGsw1UzP07XCunAAFZ5SE38ZLqI7aBrF+LVJd+AVDS4JOuKlVbzhNdc3qDtyme5D6XhjEFPHD7L61M/o7XeXBvpq6SMnr/D50NVzkHwjvPkn582CsiUP7o3NAaF3uJfcE3hFBHVolKn2JNQxwhtiO5d/kXSfa6CPUjxT8JB1DlRfzSQegExFuJSAukmN6/VMBjcLLy8eyicQfd+HX569y4UWwiq9ELDhxbsvbY6ZLik8rW/EA== 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:(366004)(6486002)(4326008)(26005)(53546011)(186003)(38100700002)(38350700002)(107886003)(956004)(2616005)(66556008)(66946007)(8676002)(8936002)(66476007)(5660300002)(52116002)(2906002)(110136005)(316002)(31686004)(31696002)(4744005)(508600001)(36756003)(44832011)(16576012)(86362001)(45980500001)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?aDhDK1hQVk1WeGYvRVRpVDV6VFJMUmJXWm9tTkoxaVk0bWFlYzdObUIyV0Rp?= =?utf-8?B?MzhYbTRPU2FMZ2Frb2JwaVJWV0laM0JHTGZEazZhSDlUeXp4MnVpUFpkaVZo?= =?utf-8?B?Mkl3TUllRVZ6ekxGWElzM016UW5mdkIzQjZORnFjWkY5cTV1SjNQVmR0VWNH?= =?utf-8?B?MkZoNElDcXlzSUY0WnYvNDFsNUkrNjZTZ1U3THJvRWR6eW0vZUJJSW1abjZO?= =?utf-8?B?ZTVYVm52ek4wOTA3MHMxaVRWNVYwMkM5SitQRDdKQ1BuaWQ4Vkk2TXRBWVNO?= =?utf-8?B?aHFHUmVVMzZpeG9HalBjVWdmQ1pFV0lKS2RlUHpmKzg2OTZjRis4Ni9yK0dI?= =?utf-8?B?cVdvMjlPeGcra2NKZi8xSzJyd1RPeDRsUGh6Wjl3cHZ3azB2RXpwTWZrVUNu?= =?utf-8?B?WXBiVUxaVVFkV3kxcjNubUN1RmcwOERZekpNUGFwWHZQWUhhSnkza0RQZ3Ax?= =?utf-8?B?ZVZQdzBvNDNVSWczTjJ3Z0xvZFBpWnZZbWJYVUpISm16YjBMN0J3VFljaCtN?= =?utf-8?B?VkNVU1dBb3gvRUt5bE56YmN1ZVUvcW9NK2lEZldOK1B6M0dvZVlhbUE4M2hC?= =?utf-8?B?Uk1mSU5OUDRrL1B5aFJXdmNGUFlHTXlLRDM3UTdBenlMTFVHelhabWdDMUt6?= =?utf-8?B?cUZ0cXloUTJXbVZhMGJZRlphUkhnYVhBd0RIdWQrUks5TW03ZVdqUnlyVjRD?= =?utf-8?B?UW9OakEvdWlhRVhPNjZRU2RkbVZvdHJxQXhWektENG5JeHNwaW9CL2NCL1U1?= =?utf-8?B?UGwrajVlV0lpSGtBYW1UaHdneDY1QW8vbVBWLzArcnNQemp3QWJBTkJRb3Ex?= =?utf-8?B?amMwN24rL1AyVWY1UkdLSnFMeUI1OFZWSHU5d2pBQzc3cnkvVG96bm9rb2xu?= =?utf-8?B?M00yMEhJU1R6YlBrdWxrTE5qczAzL2JsN25MalA2aFYzaXJZY3o2RENSOE41?= =?utf-8?B?YXZDUFB0TkpJRDNhWlNFc1dNTmtQMHE4L2dDcDJEbjRRRko2VnV2ZnB2NmE4?= =?utf-8?B?bys5WjNIT2lBV1lFKzhMSzM4MU14bExJRG1RVmZKaXBiYk0zOU42T2VWeGxC?= =?utf-8?B?WXFaWEFUUmkvMkJtTVJpbERqK0RXMHJZeXYxUnpmVHlUMGRsN1FpakVRckll?= =?utf-8?B?VklJZlRJMWVNc1FsV0RyeThwNFQ5RU1MSEh0cTYrcjRIWEVwZzRRcmMvR2RF?= =?utf-8?B?OEwrRUNRcEIvQmhzVS9oY1FOYVZNbzB2QTdIVmtrT0dUc0ZZdzVhTmVVeDdm?= =?utf-8?B?ZW5MY3l2bWQxUFlQNmZMUkpyNkNIWGIvRmN2bzRQb1RoNXJGMUs5MnFvdnls?= =?utf-8?B?QmgwbjBycUFJc25vNy9aSHhMOVAxS0J3UTc2RWV5VnFUNExjY2lwRk1KcW5E?= =?utf-8?B?MEJhS3dTZDAxUlRPVHFCY05KMU1IV2hXK1JMWjlva3BrZGduUmZQSlZzcEdC?= =?utf-8?B?TTFya0hoWE9lYU1zaWxkd21WVUxJRE0xTUREakRuNUxRZ3JvL29QSzFpOG51?= =?utf-8?B?MXB2cDQxYW9EZStIYk52eFcraE1DYm9xQllGdFd5NnFUbStzU0x3UmZndGpn?= =?utf-8?B?WTE0TXhXR0w2WHZUR3VGS1U2cGlPM3FGc2x0ZWkrcG5mSGUxYzVia29DYW9F?= =?utf-8?B?cTVFbFJxeXdGc3NuZUwxTS83dGdrV2t6U3JVbzM5WUxhWnFMbmZDVlI2Qmpo?= =?utf-8?B?YWlsRjVqMGpnQ0hhRDlEODNnSUE0ZzI1ek1KVCtvUlRhdlZGMVdGdVJDQjdH?= =?utf-8?B?ZE92THJFUHkzYVF6Q0hSeXBUSkR5aWlIZkVRbUx6b3JNMUkxQ3M3YkkwTEdS?= =?utf-8?B?SXowUGhsM3Q5eE0relRKWGhzNnNsbXc5bE5EaUhMYVdVWnE3YkJRLzhWblkx?= =?utf-8?B?Q0o2VE0rWXlDc0V3OE5zT3VJbXVYeTZ6UzJDRk12VHgvMXFtQzQrUkF5QnlK?= =?utf-8?B?UWQ3dytWOStyZDNhWUtjNHRZVlVxdE5QZlphNU9vckVVSU93VmdzQTBKc3Zm?= =?utf-8?B?ZWlXY1o1MGl6azJJN1ZNcWo3OWFZNWZaQzhScTFab2F1TGp2djM5MjVJci8y?= =?utf-8?B?R0NxVkpKM2ZGNFB2aUhEbCtUWDdCMXdKOE9LM0MxdENXaXd3SjBOU2ZidW9y?= =?utf-8?B?eW5Sc1Z0Q1FGNkRyNVZ3cTlpaWFoVlBTYkg0Wk5lTEJwdVAvdmlkZkt0QW1Y?= =?utf-8?Q?FP8d9Q7gOPxjNv7Ex+G3ggU=3D?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: ab3b1cbf-c9a1-4781-8fea-08d9b5b8fe68 X-MS-Exchange-CrossTenant-AuthSource: BY5PR10MB4196.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Dec 2021 17:27:19.8681 (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: nsdQpP3147L7knrt6rXueqj7hQareDZlWXFK64rSSIFwVUzZ6pIL0/NLsyWf5KdZJmvP6X1sNNDHetyp9nguZg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR10MB4273 X-Proofpoint-Virus-Version: vendor=nai engine=6300 definitions=10185 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 mlxlogscore=984 phishscore=0 suspectscore=0 spamscore=0 adultscore=0 mlxscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2112020113 X-Proofpoint-ORIG-GUID: E_wBlojeh1lYXQmCeSGiSIwIF3TQbdDm X-Proofpoint-GUID: E_wBlojeh1lYXQmCeSGiSIwIF3TQbdDm X-Stat-Signature: cqidwaizbshjcj7knkxn41qth9wjeb4u Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2021-07-09 header.b=veW0liEi; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=yX8OBDYz; dmarc=pass (policy=none) header.from=oracle.com; spf=none (imf04.hostedemail.com: domain of mike.kravetz@oracle.com has no SPF policy when checking 205.220.177.32) smtp.mailfrom=mike.kravetz@oracle.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 939A240003 X-HE-Tag: 1638466050-752313 Content-Transfer-Encoding: quoted-printable 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 12/2/21 04:47, David Hildenbrand wrote: > On 02.12.21 11:19, fei luo wrote: >> >> When reusing the page that has been cleared, there is no need to clear= it >> >> again,=C2=A0which also speeds up the memory allocation of user-mode pr= ograms. >> >> >> Is this feature feasible? >=20 > "init_on_free=3D1" for the system as a whole, which might sounds like w= hat > might tackle part of your use case. >=20 Certainly init_on_free will not make much difference if VMs are backed by hugetlb pages. We (Joao and myself) have thought about clearing hugetlb pages from user space in an attempt speed up launching of VMs backed by hugetlb pages. --=20 Mike Kravetz