From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f181.google.com ([209.85.213.181]:38888 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754194AbbK3PHK (ORCPT ); Mon, 30 Nov 2015 10:07:10 -0500 Received: by igbxm8 with SMTP id xm8so73950041igb.1 for ; Mon, 30 Nov 2015 07:07:09 -0800 (PST) Subject: Re: shall distros run btrfsck on boot? To: Jeff Mahoney , Christoph Anton Mitterer , linux-btrfs@vger.kernel.org References: <1448337754.14125.33.camel@scientia.net> <5659DBD9.1070802@suse.com> From: Austin S Hemmelgarn Message-ID: <565C6611.1000405@gmail.com> Date: Mon, 30 Nov 2015 10:06:57 -0500 MIME-Version: 1.0 In-Reply-To: <5659DBD9.1070802@suse.com> Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030508070401010502030400" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms030508070401010502030400 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-11-28 11:52, Jeff Mahoney wrote: > On 11/23/15 11:02 PM, Christoph Anton Mitterer wrote: >> Hey. >> >> Short question since that came up on debian-devel. >> >> Now that btrfs check get's more and more useful, are the >> developers going to recommend running it periodically on boot (of >> course that wouldn't work right now, as it would *always* check)? > > Running fsck on boot is a holdover from an era where non-journaling > file systems were the norm. It persists in the ext* world mostly due > to inertia, but it shouldn't be run on boot with ext3 or ext4 either. > As Eric noted, fsck.xfs is a no-op. We have something similar for > btrfs and have no intention of ever running fsck on boot with btrfs > except in the case of a mount failure of the root file system. The bit about ext* is debatable, the code doesn't appear to do any=20 automatic repairs on an online filesystem like XFS does (and BTRFS does=20 when you scrub it), which would indicate to me that it should be run,=20 but not forced on boot for ext3/4, assuming the FS is configured sanely=20 (which means on the systems I manage, it only gets run at most once=20 every 24 hours unless I break into the boot sequence and force it manuall= y). > >> Plus... is btrfs check (without any arguments) non-desctructive, or >> are there corner-cases where it may lead to any changes on the >> devices? > > I haven't reviewed it in detail, but a quick glance makes it look like > it will, minimally, create transactions even in check-only mode. I agree with Qu here, if this is the case, it's a bug that needs to be=20 fixed. --------------ms030508070401010502030400 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0BBwEAAKCC Brgwgga0MIIEnKADAgECAgMRLfgwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwOTIxMTEzNTEzWhcNMTYwMzE5MTEzNTEzWjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz ZXIxIzAhBgkqhkiG9w0BCQEWFGFoZmVycm9pbjdAZ21haWwuY29tMSIwIAYJKoZIhvcNAQkB FhNhaGVtbWVsZ0BvaGlvZ3QuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA nQ/81tq0QBQi5w316VsVNfjg6kVVIMx760TuwA1MUaNQgQ3NyUl+UyFtjhpkNwwChjgAqfGd LIMTHAdObcwGfzO5uI2o1a8MHVQna8FRsU3QGouysIOGQlX8jFYXMKPEdnlt0GoQcd+BtESr pivbGWUEkPs1CwM6WOrs+09bAJP3qzKIr0VxervFrzrC5Dg9Rf18r9WXHElBuWHg4GYHNJ2V Ab8iKc10h44FnqxZK8RDN8ts/xX93i9bIBmHnFfyNRfiOUtNVeynJbf6kVtdHP+CRBkXCNRZ qyQT7gbTGD24P92PS2UTmDfplSBcWcTn65o3xWfesbf02jF6PL3BCrVnDRI4RgYxG3zFBJuG qvMoEODLhHKSXPAyQhwZINigZNdw5G1NqjXqUw+lIqdQvoPijK9J3eijiakh9u2bjWOMaleI SMRR6XsdM2O5qun1dqOrCgRkM0XSNtBQ2JjY7CycIx+qifJWsRaYWZz0aQU4ZrtAI7gVhO9h pyNaAGjvm7PdjEBiXq57e4QcgpwzvNlv8pG1c/hnt0msfDWNJtl3b6elhQ2Pz4w/QnWifZ8E BrFEmjeeJa2dqjE3giPVWrsH+lOvQQONsYJOuVb8b0zao4vrWeGmW2q2e3pdv0Axzm/60cJQ haZUv8+JdX9ZzqxOm5w5eUQSclt84u+D+hsCAwEAAaOCAVkwggFVMAwGA1UdEwEB/wQCMAAw VgYJYIZIAYb4QgENBEkWR1RvIGdldCB5b3VyIG93biBjZXJ0aWZpY2F0ZSBmb3IgRlJFRSBo ZWFkIG92ZXIgdG8gaHR0cDovL3d3dy5DQWNlcnQub3JnMA4GA1UdDwEB/wQEAwIDqDBABgNV HSUEOTA3BggrBgEFBQcDBAYIKwYBBQUHAwIGCisGAQQBgjcKAwQGCisGAQQBgjcKAwMGCWCG SAGG+EIEATAyBggrBgEFBQcBAQQmMCQwIgYIKwYBBQUHMAGGFmh0dHA6Ly9vY3NwLmNhY2Vy dC5vcmcwMQYDVR0fBCowKDAmoCSgIoYgaHR0cDovL2NybC5jYWNlcnQub3JnL3Jldm9rZS5j cmwwNAYDVR0RBC0wK4EUYWhmZXJyb2luN0BnbWFpbC5jb22BE2FoZW1tZWxnQG9oaW9ndC5j b20wDQYJKoZIhvcNAQENBQADggIBADMnxtSLiIunh/TQcjnRdf63yf2D8jMtYUm4yDoCF++J jCXbPQBGrpCEHztlNSGIkF3PH7ohKZvlqF4XePWxpY9dkr/pNyCF1PRkwxUURqvuHXbu8Lwn 8D3U2HeOEU3KmrfEo65DcbanJCMTTW7+mU9lZICPP7ZA9/zB+L0Gm1UNFZ6AU50N/86vjQfY WgkCd6dZD4rQ5y8L+d/lRbJW7ZGEQw1bSFVTRpkxxDTOwXH4/GpQfnfqTAtQuJ1CsKT12e+H NSD/RUWGTr289dA3P4nunBlz7qfvKamxPymHeBEUcuICKkL9/OZrnuYnGROFwcdvfjGE5iLB kjp/ttrY4aaVW5EsLASNgiRmA6mbgEAMlw3RwVx0sVelbiIAJg9Twzk4Ct6U9uBKiJ8S0sS2 8RCSyTmCRhJs0vvva5W9QUFGmp5kyFQEoSfBRJlbZfGX2ehI2Hi3U2/PMUm2ONuQG1E+a0AP u7I0NJc/Xil7rqR0gdbfkbWp0a+8dAvaM6J00aIcNo+HkcQkUgtfrw+C2Oyl3q8IjivGXZqT 5UdGUb2KujLjqjG91Dun3/RJ/qgQlotH7WkVBs7YJVTCxfkdN36rToPcnMYOI30FWa0Q06gn F6gUv9/mo6riv3A5bem/BdbgaJoPnWQD9D8wSyci9G4LKC+HQAMdLmGoeZfpJzKHMYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUxMTMwMTUwNjU3WjBPBgkq hkiG9w0BCQQxQgRAcQ5vyXQ29Q5M9KHE+oqBJbThl2Ski0vLpV/UqissGsWXRUvT0dYrQL7x 8nD8uMiROW3KgS0cNzhR6noR3KsM5jBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxEt+DCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DAN BgkqhkiG9w0BAQEFAASCAgCO0g+h2l/zCHPfiuqHOpa2xUDzxAiM6uZKaxbkOHYugyTI0i1J /q8Ze9ckcOqwxAwmbe0OKHACJCL48zNWY8B+JV2BjulYzB3fFpRKQvP2cfR19V5a09a1Gzmt Yre1Gtp1SCHReWlTxsJzmBP64owhWTkjzmphvvVkkgl857zRu4x8vwnzDWd9Bo/hMFcV3s5V OPXMBc7v944mmWjfjJ8dGMsDuznVdHANKHlXrGLTumoOE635clFsvm9HWwV4QpmZidGAUrn6 IR9hdbEIBKXemM9ZiZT0uDJg3svEEFe/t1pzPK+qKOp4n1cOCzrpifwyqf+W2CAA1ljczrvA 7tNtJPe1foc89k1FuRpNMIi9fKfebns070wxjFNT8WBwRbg8TDgNMZtLyjb7+wnt5omZrzZ8 ze7XLGSyW7GMdENBrUWHp7up/kk10opoptQei8eGv/Nw9FSeYD76CtlG6F0qfbbIdJveO28Q /OFtOO1LqfzaBH2hM6U0z49NZUmoh26aZYQc/QnUBib8yrpKd+hA8ODN1DlMTOsPFXpQh26F KbeI63hujBVxFc8k9qQ9x4M8l3Oc5PPafvFQb7Y03y0rdPmiO5bXZaQZgnIsI7pqU8o6vmG1 wTaZICSP08yNlswt+vpq/FfdOBej/sO+HyyNbP15Mdy/qZ5D4RRUfyGVUwAAAAAAAA== --------------ms030508070401010502030400--