From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f175.google.com ([209.85.223.175]:33963 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751203AbbHTLws (ORCPT ); Thu, 20 Aug 2015 07:52:48 -0400 Received: by iodb91 with SMTP id b91so42587755iod.1 for ; Thu, 20 Aug 2015 04:52:48 -0700 (PDT) Subject: Re: Btrfs is amazing! (a lack-of-bug report) To: Tyler Bletsch , linux-btrfs@vger.kernel.org References: <55D1567B.3030809@gmail.com> <55D1CA1E.1060103@gmail.com> <55D23397.6090404@gmail.com> <55D31A3C.3080208@gmail.com> <55D4BBBB.9000008@gmail.com> From: Austin S Hemmelgarn Message-ID: <55D5BF80.500@gmail.com> Date: Thu, 20 Aug 2015 07:52:32 -0400 MIME-Version: 1.0 In-Reply-To: <55D4BBBB.9000008@gmail.com> Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms000600080708020103060304" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms000600080708020103060304 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-08-19 13:24, Tyler Bletsch wrote: > Thanks. I'd consider raid6, but since I'll be backing up to a second > btrfs raid5 array, I think I have sufficient redundancy, since > equivalent to raid 5+1 on paper. I'm doing that rather than something > like raid10 in a single box because I want the redundancy of a second > physical server so I can failover in the event of a system-level > component failure. > > (And of course, "failover" means "continue being able to watch TV shows= > and stuff") > > A question about what you said -- when you say people have hit bugs in > the raid56 code, which flavor do these bugs tend to be? Are they > "minding my own business and suddenly it falls over" bugs or "I tried t= o > do something weird with btrfs and it screwed up" bugs? More along the lines of 'I tried to do something that works fine with=20 the other raid profiles and it kind of messed up the filesystem'. In=20 general, you should be safe as long as you are using at least Linux 4.0=20 and the most recent version of btrfs-progs. It's been a while since I=20 saw any raid56 related bugs that caused actual data loss. If you are=20 using this on SSD's though, I would wait, there are known issues with=20 DISCARD/TRIM not working correctly on btrfs right now (nothing involving = data loss, just problems with it not properly trimming free space and=20 therefore causing issues with wear-leveling), and it looks like the fix=20 won't be in 4.2 as of right now. --------------ms000600080708020103060304 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 Brgwgga0MIIEnKADAgECAgMQblUwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwMzI1MTkzNDM4WhcNMTUwOTIxMTkzNDM4WjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz 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 b20wDQYJKoZIhvcNAQENBQADggIBABr5e8W+NiTER+Q/7wiA2LxWN3UdhT3eZJjqqSlP370P KL5iWqeTfxQ67Ai/mHbJcT2PgAJ+/D2Ji+aRR03UWnU/vtOwzyDLUMstqnfl0Zs+sz/CJe7x nBA5jlpjC2DKuMVfbPze7eySaen7XSGFHKE1QoVIIpQ2kVjC4nbbJQnUbAVX1Iz29WxeVGt9 XYigz3tDPf3tglN+q23E7YjQl4abTIoM7i98yV1H9gfY8lFfKZ6jREB9+n6ie2EwS3Kat2mG tl2wBx4MfRnoSQSKsLKQ5oTwhWf0JqlFwpLfl374p0Njcykej9/jnWG8Ks1V/AXTHqI4eyIP Mf5yMZkPv7n7LS9WWKdG4Nd38iv4T2EiAaWsmgu+r81qL5CJu9AyA0SBS4ttKf6k3e63w2Mv N9R45vpQ3QhAhfWyFxFhZN95APe3YECDG3+XIRJpRYPEtHuIsOyzI70ajF93gg/BidvqKsmV MM2ccktDMfqwZXea6zey7F8Geu9R7BqjXmG2HlNuXu7e/xnHOgXf5D3wPmnRLlBhXL1Ch97a w2KjaupjpAHfFjv5kGnZXN87UvvlwzIZiKXwa3vTDwK+rrKn/sHPkfDZPSiyt/ZBIK6lX83P 34H/CzGg+Kx57rHYOIHGumIvpDa5vfWp8O0sGgawb1C2Aae4sTUVIWmIjVuGI062MYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwODIwMTE1MjMyWjBPBgkq hkiG9w0BCQQxQgRAxtv20hS7eJajz/1m/xt2RMJoCDBXPa4RqbaMQrsKhSZQ5AUmH3wHFZw8 dL09kv08ZfciP6vS4UeSpEz7TfjEdzBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgAFGqoBqFD1N945k6ZaUC9L+RZK0H4gpHcLp0F8WxnV6ZrkzxS+ R7TSko06rOm6Kl4vWHdjkhj91h1IItAPo518hx/2oqWUzfB1oGVucqIBW4ZvsYAU1XXymE8E u5eI88EgUM8aFbd/Lh5k+1KKcAF3VoXW5+p1QIUjGQYbBvqeA0wCnOcWo3/+VTjhFTTEN6jE 6gZgxwEG0lzWHmSvlEFGeBQZjEbBq/Bu9P/hIJo8FL+RxbW+C8EsByuxwBM1XItz/4UEBbCq z+LyG00TERrW1HnHdyN2fNRfX4YVE8KbW7LvwN/8SFDOcMrfiB+CogTAM5QhiJrBNr8M9ss1 PvLVJmJ8pd2LmCpmrhseHv72x97BkDgwB+1NrZr6m3NIIoXgsP1j7TLmsXcDpDiXypWPvPwn 8jMK4ydlCm9cgQMtyXxJM9k94Y5nB3YUbyXu6hXhdIOrLhHHj0WsN9iABN9Zd3Az1k6f1WUX uu8O3p8Tf8Hq8h9KotuN+nvjA0/+TtWpEhDTV1+9cUds8XRM9n/zXM6zstsUYJG5mVPRF/9d v1prDCeGt2KPVIpGbRXeaOL0KTAsuCWWsWHOf+V2NUJasZzCRuylAofmz6USCs3NGU93icyV 6q69j9CXM1hNRelR/vxJu1m4+o9HhA9TRsiS6P3ZhlKhE8UxX7Dnrr97qQAAAAAAAA== --------------ms000600080708020103060304--