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 lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 92C56CE79D1 for ; Wed, 20 Sep 2023 13:58:26 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-4.v29.lw.sourceforge.com) by sfs-ml-4.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1qixii-0004X0-Jf; Wed, 20 Sep 2023 13:58:25 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1qixih-0004Wu-EL for linux-f2fs-devel@lists.sourceforge.net; Wed, 20 Sep 2023 13:58:24 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=MIME-Version:Content-Transfer-Encoding:Content-ID: Content-Type:In-Reply-To:References:Message-ID:Date:Subject:CC:To:From:Sender :Reply-To:Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To :Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=4mqUiXBysWSrAjbIn2bo72BSbBFc4mdnL3V0feLD1eU=; b=aithafnXK0CS7+gNmDN1iUiqZf a/BoSIk0QgcUSlWmyGA5ilU0wOK06sT8yzIjnw2gQ6+5JqwDBIApy7mzZxkrx8RdcD+C72SwdsOz/ S7xQbpfnysH9N7ekq2ln86uoxUyZcIExjHPrn1GkSD+5NxOGQvEbCTruUWINnxYVwJGA=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=MIME-Version:Content-Transfer-Encoding:Content-ID:Content-Type: In-Reply-To:References:Message-ID:Date:Subject:CC:To:From:Sender:Reply-To: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=4mqUiXBysWSrAjbIn2bo72BSbBFc4mdnL3V0feLD1eU=; b=mt+U0h2Vc7imCElR4/0+xDjMeO E2jugNDDapaVEYWZpKd3OEuaG1n7PfBqI+lMVynd0jaYkiHz7+0oTHf8e/TZaz4uN6JO7bhXBEjDD I+rk+oy5e8/pLA2ndpczgjNYSPn0OMnxl/lS+ekKOPAIIutbr3Yz2UjKcfZEOpEO0Gjg=; Received: from mx0b-00069f02.pphosted.com ([205.220.177.32]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1qixiZ-0007QL-O9 for linux-f2fs-devel@lists.sourceforge.net; Wed, 20 Sep 2023 13:58:23 +0000 Received: from pps.filterd (m0246631.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38K9sh7K031087; Wed, 20 Sep 2023 13:57:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=corp-2023-03-30; bh=4mqUiXBysWSrAjbIn2bo72BSbBFc4mdnL3V0feLD1eU=; b=G0aV8HdTG/QFwxCGAKkuoFnI+8HZ9g0Y0HIgm7M6FNNTCWFNod8F0Pobl3EWAZNRR8CQ F1wLpmo8JfHeCjqevpNDSMOTDeOdtJIAW+ifm+9oBJrLnYNJfTBs6WuBuTuFZK+dkK3x hR2RSQpEa231UJasKCLnQ34Ppa58pHPuuVV4YNH4eEVtoEjts3IueqA0sOClCevwRiCH fud9MB/ERlliPtpes3gFE8FuBFKbgPOR6KPaRb1zudihmQ/BJdnPpmqqR1Htw5Csf+/+ osaxy6CASJ0zWPiAUs8I8+iOylqjhu9haJK6c+5olHUE8gud+gmoXd/fsKkKqT0MzHSG Yg== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3t5352ydrb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 20 Sep 2023 13:57:26 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 38KCaVSi002078; Wed, 20 Sep 2023 13:57:24 GMT Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10lp2109.outbound.protection.outlook.com [104.47.55.109]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3t52t6vnpm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 20 Sep 2023 13:57:24 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=bmv6srboKPeoI8d0Hk7VrwirSj8R7LcPoxPUSpt8Kyzi1ASn2dLQbdunTOuXARay0LM9VVsg+AiI3x00cDj75VAcO7a/NkNOsnqQTQJLYKx0kJKJi3MMol0Vul1sf9k9LD3T39wbpzligWVziultPz79pJd1BPqh7yhF7dxVSY2aAQ0uK3wSetJ6OwXUzo8BFUk3GlmUvjke5tF1MCjIfv0BRB4fTLEhtBBOejNybGf7wqE8nC1k+TY70wBdd7Fi/MFoOO/UdrQwDKabj6uYw2HsJVYf7R312QLoR4gnrVAKXHHK7KSUgMhzoVzDjZlVj5Qwllm6Xr/5P4tiYcnkCw== 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=4mqUiXBysWSrAjbIn2bo72BSbBFc4mdnL3V0feLD1eU=; b=oMXtZqHpBolI1NVS/DDH8J4sHN/yqGVnTJ6xy1g3+r7om9vv8VX3soXkHWTgtebgbp80+4wBEdpBHYbLC/53u/WaO/ECE4kir0bZ/lykK1nAxRyH4qTnUsT5vKQNwHIhOvyLZzIUDk2VtlIWTIkgD5SBvPsW2eq63UAAev3e5Nt0Pcoo7ESNI0T1btvxRsbvkW2LSbje7jnEB+3rjofaloHBY67HeVSxL5rsGGzp9Q9L7VscB2XG/DFVJEmFuxnyzreV55msWWOMRT8yMAi+v2Sf28zDCxqR8Kps//rKLiB+Vg0/mTt0dyFDbAH6uIaKmrqncshdGyMFWB8mIVYRrg== 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=4mqUiXBysWSrAjbIn2bo72BSbBFc4mdnL3V0feLD1eU=; b=gCQ82UaU0/eGe9/NfLz5dggdxq0JsBg7dJKN5lFBQ23XsyTkQ3OBirVbjOwq2f+6JnyFflvipA7t5nVgyc8nUgrTCudsBSbxuVBDqKVfzLDUrxHlIF1moQHNJXAQ3FWVTGCidBCBSHbJFyZGcQFIUrOXw3yyqZnjoKkhB5N89cM= Received: from BN0PR10MB5128.namprd10.prod.outlook.com (2603:10b6:408:117::24) by CH3PR10MB7138.namprd10.prod.outlook.com (2603:10b6:610:122::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6813.20; Wed, 20 Sep 2023 13:57:20 +0000 Received: from BN0PR10MB5128.namprd10.prod.outlook.com ([fe80::bffc:4f39:2aa8:6144]) by BN0PR10MB5128.namprd10.prod.outlook.com ([fe80::bffc:4f39:2aa8:6144%4]) with mapi id 15.20.6792.026; Wed, 20 Sep 2023 13:57:20 +0000 From: Chuck Lever III To: Christian Brauner Thread-Topic: [PATCH v7 12/13] ext4: switch to multigrain timestamps Thread-Index: AQHZ6sjv7JGmOLGi70WrXuPbQ19SCbAh/K6AgAAH9ICAAFNcAoABDvAAgAAa1ICAAAT4AIAAFJaAgAAjz4A= Date: Wed, 20 Sep 2023 13:57:20 +0000 Message-ID: <57C103E1-1AD2-4D86-926C-481BC6BDB191@oracle.com> References: <20230807-mgctime-v7-0-d1dec143a704@kernel.org> <20230919110457.7fnmzo4nqsi43yqq@quack3> <1f29102c09c60661758c5376018eac43f774c462.camel@kernel.org> <4511209.uG2h0Jr0uP@nimes> <08b5c6fd3b08b87fa564bb562d89381dd4e05b6a.camel@kernel.org> <20230920-leerung-krokodil-52ec6cb44707@brauner> <20230920101731.ym6pahcvkl57guto@quack3> <317d84b1b909b6c6519a2406fcb302ce22dafa41.camel@kernel.org> <20230920-raser-teehaus-029cafd5a6e4@brauner> In-Reply-To: <20230920-raser-teehaus-029cafd5a6e4@brauner> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-mailer: Apple Mail (2.3731.700.6) x-ms-publictraffictype: Email x-ms-traffictypediagnostic: BN0PR10MB5128:EE_|CH3PR10MB7138:EE_ x-ms-office365-filtering-correlation-id: 191ae751-f64b-42ff-3af0-08dbb9e1820d 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:BN0PR10MB5128.namprd10.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230031)(136003)(396003)(376002)(366004)(39860400002)(346002)(1800799009)(186009)(451199024)(6506007)(53546011)(6486002)(6512007)(478600001)(83380400001)(26005)(2616005)(2906002)(7336002)(7366002)(4326008)(7406005)(7416002)(76116006)(54906003)(66446008)(64756008)(66556008)(6916009)(66946007)(66476007)(316002)(8676002)(91956017)(5660300002)(8936002)(41300700001)(71200400001)(86362001)(36756003)(33656002)(38100700002)(38070700005)(122000001)(66899024)(45980500001); DIR:OUT; SFP:1101; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?60avSYq2fwYZ7dG+1aS5kmkpnkeKwXxhURWlbIIn/9mqvpayoyRHzaeB03lD?= =?us-ascii?Q?m6okOLiMlCh9sI8WMzFkqvGmgadQgYjVrT+eJl2VMyvQ5dxSl/i3sJw98xtj?= =?us-ascii?Q?nhc6XTHVFsvw4D1+wRbCQiHhR7RNjr5PhQKCB60jBg/r8GFtqD1jOwJakOYU?= =?us-ascii?Q?2g3QxIxFA+gPe6vr9rsLakM2JahY8oEe9PQCW0kWlfIhHXqy3nXYACOFa9kR?= =?us-ascii?Q?/cFfbNzc5BzL+4UFEXB0avbAvB5b6Oyyv0WNOPFF6w6WXZuyT8c65GlhjaLg?= =?us-ascii?Q?zjECrKxzQ5zjlR4VbETlkpYWWtyGWTnY0U96B6x6xFx2Rg0gVJCcEoHjDETV?= =?us-ascii?Q?Adg9VLh+PVhAI+G5Gezran6AOcaRTmOoixkyzTg0XKOcSg478Pmjc9vpDKpB?= =?us-ascii?Q?BvOhgj+/AdeoXdgWH9WrW79T/NyYJw+xaXN5Y4yj+mRXtgyd3EHsjafpHajq?= =?us-ascii?Q?K55UB4M4ViV9d5HUMC44iYtkC3I4R5vEW886jgOy0ftHI/gfWJZvlOxsO1SK?= =?us-ascii?Q?Ma4v0Ij+DrxvEDnVzJ2P+hyDZ9OXbY1/tfKDWef6fHt2l/VlFofoMXrqfg3A?= =?us-ascii?Q?klo9kn3dOpqJDmtYheUOnMGEynSkyQNWc8YFWGj30bxSvJS/wnCx/6fYPfoS?= =?us-ascii?Q?zLyeRt+kGCydaJYyYr1qFY3OgmX6gip6lfiQfgO9S0+VZsOj8Zl7G4BKvieR?= =?us-ascii?Q?4JHQyFhKTNF/tEji9FctKf86eUL0zPAJ4G4JApyR0Hs+tIdlBlu94bCcUAXt?= =?us-ascii?Q?7Wwj9bc0jVfaCfqqfI1sQwnDnD9ie5Km8YJNkQpjQlY66idznjS8TAXV+Tiv?= =?us-ascii?Q?5nLDUfI0Ky8Tqa9PHW/J67K6SWFA2+tuQAjAx0VOTNraYyuJQRf6QeeEh1A2?= =?us-ascii?Q?XPZJBRp0iYpzwYxS8D2hUHLtmJUr/pM6kOnLY/ajmkW42xRmyjxTNG/6gnxt?= =?us-ascii?Q?gkyGzr4vwReE2M/JBkVXSJSIBzVyXDbF+kJBge4Mdo8qDifOkghMD0zRyORS?= =?us-ascii?Q?s34n9u4QVKDVJS5ZbaqwsH3Nj1CA2HiQa1VHq16mJoDx/MtfOFBASwccICMy?= =?us-ascii?Q?1BU1R19qOqxdLRhAtzvSdm7tH8HEfC3Ho/rCFyXJh6C+g2hT9ZL3QgFgHdHV?= =?us-ascii?Q?ZQtYJwjy3vGCHTAmXphXL8G16+cvsHTaUm+lIF2aYFHo4PVNz0DXK7DgU0wu?= =?us-ascii?Q?VnTw2PZnWBPgU0kJ+NeDmE8QunGs9n75aUYAAXyZLI7etqXhqWrLoEqEEije?= =?us-ascii?Q?opCXk5INovHsb2pf+E1elAL7GUeukuL7gDd/Y7yWbsmwVA9dKRE36oMmmDXC?= =?us-ascii?Q?PibH9bv1i7paXH9y4io5zZQrwmpO20J2jCXCseWuWMAYhxS9wH39aw/H0xn+?= =?us-ascii?Q?EYOKTz66TkMyXPtMAV62d2qYVeGidTt6lBtmb81FaZ/ek5a4BIx2kpF8baTX?= =?us-ascii?Q?EbKi0hzUGO/gmZbXiPLUkrEyY7vxm7Ce03xBC5/9eepbG0Gab1gP0N2GO/sY?= =?us-ascii?Q?PFPBAYOekJgeGIwFKma63umXwV344zFQO/imsOFZegRXsnzbY/xaD97je5aL?= =?us-ascii?Q?owZgvydQQEuuMr+bIXR9KfjZdL6hW0MG0oxtQbBEwDfS3PPz9tsLLBJu8UbK?= =?us-ascii?Q?MQ=3D=3D?= Content-ID: <0C645C8D819FE4428F17CF964FD859C3@namprd10.prod.outlook.com> MIME-Version: 1.0 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 2 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: =?us-ascii?Q?Yv+C8y2Cckn475Yhj3ETSOj/qvDGxFNXhQvLUEYI0V+DCO8O6kmxB7c/mBjM?= =?us-ascii?Q?BPh5KhfZquc5QrPv05/vstysdpT/N/uimg9vUjb4Ez/VgRVuasyv0azVgN9c?= =?us-ascii?Q?M9oBsmXFage8g4x5Qyve6od0sROFXOU1cHq6rlXjESrm87rQDKp6aTmTowms?= =?us-ascii?Q?VJXLEZ4mBLJmlXdpQ98iEovnGTNVfynA6WBO25aV0YLRvZ1rEjT6k+3SnKE/?= =?us-ascii?Q?RuNgnPNt680fSnTwQ8++XcGGg5QXrEhoo+fILdwFoGm5BcTm4eHHRb5TwK25?= =?us-ascii?Q?za12DNzOZCgb9dvumdLsHkHiMSFVDlVcW/Omvppqw2pOWf1llROwuDJZfLd/?= =?us-ascii?Q?96PmPU/4jR3Dt2bBWwXj1N5psornBSdE+1qJOILqgHczZGKqHhrNynwbrc1z?= =?us-ascii?Q?Tau82jq5BkuSPX4SSbSfO3FcxbqMwtl3A0M3S3SsQxUG4twIjvWl3IhMT+8j?= =?us-ascii?Q?/JzUAxfLLFdzef9b8kqHurXwQmKnfiRDgOAfWnEpbkK90ArXBTMkyMNrdHtI?= =?us-ascii?Q?VR0N+x3Gkg/gi/fKTkySZv76ZiD8DT7rpLezSKR2St2kcmc71Wr7J3eZbaj/?= =?us-ascii?Q?K8QWmPsGDZizADjgeULPPp5SY6cOZoGyA7J763zVdlGQKuPUkMgXzzPTuxpa?= =?us-ascii?Q?mokXFuvvxVJPtKup8+EfIztqgIdcevWw2NCprXXW7TTv7xXgr2awY6dTV1R0?= =?us-ascii?Q?j50/99NtaCSfjcWWWA7yFJSFmeq7Pm2ckYvdjgmpYXh3kiXrY4p05Wotf+8z?= =?us-ascii?Q?nBpiBaoXReiCOZKMuGnn8Ycsxp5VhJrXUjYZhy91NCUewZgxT0aLR/iFMyfT?= =?us-ascii?Q?HplapJyuhaaxfuNF/l53lHdbduOAdRfC/JXygg0IMzdmsEbuEESw6gh1RIVK?= =?us-ascii?Q?mnV7NL9Syh6bZGMGePdsfoBNZEO3bw2SAuLWuMh5329AaOXMT5WNsfn4bKHi?= =?us-ascii?Q?kUtc0ZYCk/TfWL8HfV4AcGU9w2fhYShyOshvQVjwurStWUpHeOH43rt6DECI?= =?us-ascii?Q?HWYP8BKtGuLXNMs6SG+sG/q7FvjmS5DfDNLl803D2sKr9AiJ4PZET0a3hvHQ?= =?us-ascii?Q?UN23kTV1H+doMdAxA1W1/ioecQrzkU5IAaedPDWI4DcANn8fiPL+Y7SrfBjK?= =?us-ascii?Q?r0NkuytYSPGyM+we3fEmGRztOfeqmABVbHD3dHD3PBaSyfsT7rN4/jfOisJr?= =?us-ascii?Q?oBdYR8EhKc8Hi0jWujrZd/PxkrqWFdfsBUgDcmpEZ44tLKpOJjiAKfojLFi2?= =?us-ascii?Q?hEOsIAH0FebymDtAXdukCDQN/icZNyomqxCFZ5aM/jrgCuT/U+JDT9WmjJTs?= =?us-ascii?Q?Yv89tpeBaMD5irl2PUR5Jzr1wqCQF1X1GxV0cD+3pfoCWEMJ5IXPxm8wY6U7?= =?us-ascii?Q?C6mEhW3AjLSoGsIA81DD1mgwbi81CPepT/YUjnz54unCwE7YEPZt1Op6qm82?= =?us-ascii?Q?dnw2OiLmL/UfVaPKUHfMMk2oXc6GQxdjs6MOj8l3vVUVaEPxIHTq0KYjKwt1?= =?us-ascii?Q?r9y2PQq6FYOQgeyOo2XAoQb9xF2S5KS4AOE8XwTs87tw+mKF19eMqAKxZyOy?= =?us-ascii?Q?LhJuwZxoV23/h7gpLFZKZV3gQnt4vuoakBPmF+WKFxYoB2tGwFYeAtsz5zSU?= =?us-ascii?Q?PvGpH4eRroTf5Vg+pQ3hii3oFqdOO69NoZQalEpIp6mh49yh1iHd0zVi35d6?= =?us-ascii?Q?TnvRRMUWMxvMCnmc5SGvJLik37FN733cFReh4SEpSBuj4THIs1u7fLgp9Kou?= =?us-ascii?Q?nxS5K3P0+CAFU7uBK8o90l8B/LUB0Ni12NNW42IMp67jjCSf0LFqdpZrWJVt?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-1: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN0PR10MB5128.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 191ae751-f64b-42ff-3af0-08dbb9e1820d X-MS-Exchange-CrossTenant-originalarrivaltime: 20 Sep 2023 13:57:20.3575 (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: gt2gy5hUzNI9y2DFfbA5T/SEsjfbKDQdcFZztpnR1XSkHUXgHRhK7SPca5XNr2tRzii70htTIcf7Ehl7tM74yg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR10MB7138 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-20_05,2023-09-20_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 adultscore=0 bulkscore=0 suspectscore=0 phishscore=0 malwarescore=0 mlxscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309200114 X-Proofpoint-ORIG-GUID: 1sVYCLy-lrnGMYMM408XV_XkB2BJbt1t X-Proofpoint-GUID: 1sVYCLy-lrnGMYMM408XV_XkB2BJbt1t X-Headers-End: 1qixiZ-0007QL-O9 Subject: Re: [f2fs-dev] [PATCH v7 12/13] ext4: switch to multigrain timestamps X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Latchesar Ionkov , Martin Brandenburg , Konstantin Komarov , Jan Kara , "linux-xfs@vger.kernel.org" , "Darrick J. Wong" , Dominique Martinet , Christian Schoenebeck , "linux-unionfs@vger.kernel.org" , David Howells , Chris Mason , Andreas Dilger , Hans de Goede , Marc Dionne , "samba-technical@lists.samba.org" , "codalist@coda.cs.cmu.edu" , "linux-afs@lists.infradead.org" , "linux-mtd@lists.infradead.org" , Mike Marshall , Paulo Alcantara , Amir Goldstein , Eric Van Hensbergen , "bug-gnulib@gnu.org" , Andreas Gruenbacher , Miklos Szeredi , Richard Weinberger , Mark Fasheh , Hugh Dickins , Benjamin Coddington , Tyler Hicks , "cluster-devel@redhat.com" , "coda@cs.cmu.edu" , "linux-mm@kvack.org" , Gao Xiang , Iurii Zaikin , Namjae Jeon , Trond Myklebust , Xi Ruoyao , Shyam Prasad N , "ecryptfs@vger.kernel.org" , Kees Cook , "ocfs2-devel@lists.linux.dev" , "linux-cifs@vger.kernel.org" , "linux-erofs@lists.ozlabs.org" , Josef Bacik , Tom Talpey , Tejun Heo , Yue Hu , Al Viro , Ronnie Sahlberg , David Sterba , Jaegeuk Kim , "ceph-devel@vger.kernel.org" , Xiubo Li , Ilya Dryomov , OGAWA Hirofumi , Jan Harkes , Linux NFS Mailing List , "linux-ext4@vger.kernel.org" , Theodore Ts'o , Joseph Qi , Greg Kroah-Hartman , "v9fs@lists.linux.dev" , "ntfs3@lists.linux.dev" , Jeff Layton , "linux-kernel@vger.kernel.org" , "linux-f2fs-devel@lists.sourceforge.net" , Steve French , Sergey Senozhatsky , Luis Chamberlain , Jeffle Xu , "devel@lists.orangefs.org" , Anna Schumaker , Jan Kara , Bo b Peterson , "linux-fsdevel@vger.kernel.org" , Andrew Morton , Sungjong Seo , Bruno Haible , "linux-btrfs@vger.kernel.org" , Joel Becker Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net > On Sep 20, 2023, at 7:48 AM, Christian Brauner wrote: > >>>> While we initially thought we can do this unconditionally it turns out >>>> that this might break existing workloads that rely on timestamps in very >>>> specific ways and we always knew this was a possibility. Move >>>> multi-grain timestamps behind a vfs mount option. >>> >>> Surely this is a safe choice as it moves the responsibility to the sysadmin >>> and the cases where finegrained timestamps are required. But I kind of >>> wonder how is the sysadmin going to decide whether mgtime is safe for his >>> system or not? Because the possible breakage needn't be obvious at the >>> first sight... >>> >> >> That's the main reason I really didn't want to go with a mount option. >> Documenting that may be difficult. While there is some pessimism around >> it, I may still take a stab at just advancing the coarse clock whenever >> we fetch a fine-grained timestamp. It'd be nice to remove this option in >> the future if that turns out to be feasible. >> >>> If I were a sysadmin, I'd rather opt for something like >>> finegrained timestamps + lazytime (if I needed the finegrained timestamps >>> functionality). That should avoid the IO overhead of finegrained timestamps >>> as well and I'd know I can have problems with timestamps only after a >>> system crash. >> >>> I've just got another idea how we could solve the problem: Couldn't we >>> always just report coarsegrained timestamp to userspace and provide access >>> to finegrained value only to NFS which should know what it's doing? >>> >> >> I think that'd be hard. First of all, where would we store the second >> timestamp? We can't just truncate the fine-grained ones to come up with >> a coarse-grained one. It might also be confusing having nfsd and local >> filesystems present different attributes. > > As far as I can tell we have two options. The first one is to make this > into a mount option which I really think isn't a big deal and lets us > avoid this whole problem while allowing filesytems exposed via NFS to > make use of this feature for change tracking. A mount option isn't hard to implement, but I think it would be a mistake. As Jan pointed out, the two alternative compromises are often very difficult to choose between. Tossing this decision to administrators doesn't seem like a responsible way to handle a question that might result in, at the least, unexpected behavior, and at worst, data corruption. Plus, on Linux, often times files are accessed locally on NFS servers as well as remotely -- how does the server's administrator pick the correct setting in that case? > The second option is that we turn off fine-grained finestamps for v6.6 > and you get to explore other options. You could put it behind an EXPERIMENTAL Kconfig option so that the code stays in and can be used by the brave or foolish while it is still being refined. > It isn't a big deal regressions like this were always to be expected but > v6.6 needs to stabilize so anything that requires more significant work > is not an option. -- Chuck Lever _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel