From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f177.google.com ([209.85.223.177]:33679 "EHLO mail-io0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751255AbbHNT7B (ORCPT ); Fri, 14 Aug 2015 15:59:01 -0400 Received: by iods203 with SMTP id s203so95925950iod.0 for ; Fri, 14 Aug 2015 12:59:00 -0700 (PDT) Subject: Re: The performance is not as expected when used several disks on raid0. To: Chris Murphy , Btrfs BTRFS References: <55CE4682.3080106@gmail.com> From: Austin S Hemmelgarn Message-ID: <55CE4866.6060207@gmail.com> Date: Fri, 14 Aug 2015 15:58:30 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms040603030407050100060507" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms040603030407050100060507 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-08-14 15:54, Chris Murphy wrote: > On Fri, Aug 14, 2015 at 1:50 PM, Austin S Hemmelgarn > wrote: >> On 2015-08-14 14:31, Chris Murphy wrote: >>> >>> On Fri, Aug 14, 2015 at 9:16 AM, Eduardo Bach wr= ote: >>> >>>> With btrfs the result approaches 3.5GB/s. When using mdadm+xfs the >>>> result reaches 6gb/s, which is the expected value when compared with= >>>> parallel dd made on discs. >>> >>> >>> mdadm with what chunk (strip) size? The default for mdadm is 512KiB. >>> On Btrfs it's fixed at 64KiB. While testing with 64KiB chunk with XFS= >>> on md RAID might improve its performance relative to Btrfs, at least >>> it's a more apples to apples comparison. >>> >> I have a feeling that XFS will still win this. It is one of the slowe= r >> filesystems for Linux, but it still beats BTRFS senseless when it come= s to >> performance as of right now. > > Yeah I was suggesting with a 64KiB chunk the XFS case might get even fa= ster. > > Ah, misunderstood what you meant. Yeah, that will almost certainly make = things faster for XFS. FWIW, running BTRFS on top of MDRAID actually works very well,=20 especially for BTRFS raid1 on top of MD-RAID0 (I get an almost 50%=20 performance increase for this usage over BTRFS raid10, although most of=20 this is probably due to how btrfs dispatches I/O's to disks in=20 multi-disk stetups). --------------ms040603030407050100060507 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 hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwODE0MTk1ODMwWjBPBgkq hkiG9w0BCQQxQgRA1aFVaHFTL11SzmJXDxvk1ngszxli1lzbyn+KmMOezdCBeZyphLlt7DEo Hy4CcrR3KXvjvwIc8megdp7bCAj9ZzBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgB4jZQXioqZc6p8PgkMZZlSx5p6N0UDTBCYzG6g2UGo+Eafa0ly wKj5B8GBc+OuVkjMerDJVro2soGPd+EjHekrKkJqXxj9Li183/p5yj13phPTW7Oi6pxUlze4 29juxXXNF2df5+HkB7Vs6+hP8rvUddxrIcKPX9EKaZdLbRN32yY5qSmXPJuC2iWCkLW8ofsK X/vbQj70rjVJugwyowUkUmxoIqWI+bPbtSTTSb8GmTPX6YETKBzvz/dGFDbtJ7exClDDieWZ sSs8oeWb8XZX5H6oLK2XJA42/otgIJfLmcnWLQp+Yesq5tnWkjdQeQkhk4AgnJOiJfDtiOzW wcNe2AexO/18BLvQ6tMmDFx+m8ngN7NiVhTlD1T7R/tjqrZ1YZXEZJHuG/WrKglQ9kcugqkl 1to0llHzijhTxnutGPEm9OfbTiPo4TBCcIVLI4IaT8r3LkOMJ/U7F/mHLmvG1bE3kiVrnFZ2 Zz5JdJ8lachYmEZcgOXoR8Bvasyo+ctuUhDFoYujWxeE1Xi4RP0uTmbMVDuiPMDWvxdxk703 iwWyH+VZv8DuwFjuzoHAaKG6VntFYQvWFg0wE5RxNrHs3urwMsEEuCvM22l/dPeGVncceOfE k41+sfinSHGmo3bHG4tBCFTz983gbEBmu8GjUEhLs2t9bRGMky1jHgdhpwAAAAAAAA== --------------ms040603030407050100060507--