From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: util-linux-owner@vger.kernel.org Received: from mail-io0-f169.google.com ([209.85.223.169]:36071 "EHLO mail-io0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751646AbbIIMkd (ORCPT ); Wed, 9 Sep 2015 08:40:33 -0400 Subject: Re: mkfs.btrfs cannot find rotational file for SSD detection for a pmem device To: Boaz Harrosh , "Elliott, Robert (Persistent Memory)" , "dan.j.williams@intel.com" References: <94D0CD8314A33A4D9D801C0FE68B40295BD1BF1F@G4W3202.americas.hpqcorp.net> <55EEDAE8.1060905@gmail.com> <94D0CD8314A33A4D9D801C0FE68B40295BD1EB13@G4W3202.americas.hpqcorp.net> <55F017CE.1090505@gmail.com> <55F02239.3090809@plexistor.com> Cc: "Knippers, Linda" , "util-linux@vger.kernel.org" , "Kani, Toshimitsu" , "linux-btrfs@vger.kernel.org" , "linux-nvdimm@lists.01.org" From: Austin S Hemmelgarn Message-ID: <55F028B7.9080707@gmail.com> Date: Wed, 9 Sep 2015 08:40:23 -0400 MIME-Version: 1.0 In-Reply-To: <55F02239.3090809@plexistor.com> Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms060300090808010408050400" Sender: util-linux-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms060300090808010408050400 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-09-09 08:12, Boaz Harrosh wrote: > On 09/09/2015 02:28 PM, Austin S Hemmelgarn wrote: >> On 2015-09-08 16:00, Elliott, Robert (Persistent Memory) wrote: > <> > >> this may actually make things slower (the particular effect of SSD mod= e >> is that it tries to spread allocations out as much as possible, as thi= s >> helps with wear-leveling on many SSD's). >> > > For DRAM based NvDIMM it matters not at all. For Flash based or the new= > 3d Xpoint it is a plus, so no harm in leaving it in > Looking at it from another perspective however, a lot of modern RAM=20 modules will stripe the bits across multiple chips to improve=20 performance. In such a situation, BTRFS making the effort to spread out = the allocation as much as possible may have an impact because that=20 allocation path is slower than the regular one (not by much, but even a=20 few microseconds can make a difference when it is getting called a lot). --------------ms060300090808010408050400 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 hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwOTA5MTI0MDIzWjBPBgkq hkiG9w0BCQQxQgRAZkDMzo7WfvNZ/okWJ9PiSOhpLTfeQvMisbH/xPRijff+BQmP0T3Uviha LgJolOA9WPV9yoX+e7rbtsxAUdL1pTBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgA3Le3I9phDsihc0IJI82ED5/wTIn5BtbEe096G6fZ8WajdCX8B dbektg8ZcvURMftBsZDpv5WZrycI+xXkV9DmnlIFQQA1cBeTLhuIQu8yN+/cbbQdddT1mIm1 wCsVasoehRJuB7Fban2eXmOy5w68coZvq5yaY/RzhnupO65rqfNWN7B5uB3sHvLpUP7K3eCe GnxCDC9F0/ayMGT+BuIlzoXajA+u7d+G3pOimehkD/AxGjiUHVqpq1iJDaAU2XRsIYg4Q2rb QuTGRQdYQscm5bmt4E8sDB7VC1holIXKJagfpfBGFVVkzU7HJx3+fXvTcBRhplIx4Spl6ApZ 0DJ7CKEk86mchM5U+AKOOvhzuKafZPZwvX5XDKPvP5A5RWbt4HH87NAYtrXnMO+53OoC/vPK tjOVP8umqVORsqkBvVsgbnH67LCmhKOu5b0d0tfcJ6CYKOkIZrJtHen+uL4c8rmGtDtg2oNd xMZ+nX+o02GznZEx8caGwgivKiMToVDETp4oVaDndktM2tduDU3S5AGcpjx3SVhMTenva+35 fFCKAIPkErHS2hHkn4t9/YMqeCWRx2LwuRnOPpbSX5JJElSZAHwaz20Zv9DIG4uFwY7Qh9px HrYuVDGeDR21pQY4aWQYM3q0iOXe29+kUc6k71JNXkXge4xxAW2UnTT88gAAAAAAAA== --------------ms060300090808010408050400--