From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f173.google.com ([209.85.213.173]:38900 "EHLO mail-ig0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750891AbbJ2UBt (ORCPT ); Thu, 29 Oct 2015 16:01:49 -0400 Received: by igbdj2 with SMTP id dj2so38672546igb.1 for ; Thu, 29 Oct 2015 13:01:49 -0700 (PDT) Subject: Re: Bad fs performance, IO freezes To: "cheater00 ." References: <562F638B.1040701@gmail.com> <562F7C7B.6060408@gmail.com> <562F97B5.8000108@gmail.com> <56322679.8050001@gmail.com> Cc: Liu Bo , Henk Slager , Btrfs BTRFS From: Austin S Hemmelgarn Message-ID: <56327B01.7010002@gmail.com> Date: Thu, 29 Oct 2015 16:01:05 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms050303050408040402030305" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms050303050408040402030305 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-10-29 11:49, cheater00 . wrote: > Hi Austin, > seek times are fine, but this literally freezes my computer for a > split second. I've had to re-type this email twice because the freezes > meant letters I typed would not arrive on the screen. > USB disks are so common they should not be having issues. That's debatable. USB is commonly used because it's almost impossible=20 to find a system that doesn't have it, not because it's reliable. The=20 original intent was for it to be used for stuff like mice and keyboards, = so it was designed with low-latency and fair scheduling in mind, both of = which really hurt performance of bulk data storage devices. > I have 4.3.0-040300rc7-generic #201510260712 which is just three days o= ld. That should be perfectly recent enough, although FWIW, the official=20 version of 4.3 should be out this Sunday. > > Please advise. Isn't it better to *not* use a vm to debug this? That depends. For something like this, it could go either way. I just=20 use a VM because that's what I always use, because it's nice not=20 crashing your system when trying to debug a kernel panic. > BTW, if we are talking about slow speed making things worse, I could > try downgrading the cable to usb2. > Is there a standard virtualbox VM that I could use? In general, it's pretty easy to set something like Ubuntu up in=20 VirtualBox, the install is essentially identical to regular hardware=20 aside from the initial setup of the VM itself. The documentation for=20 VirtualBox is really good, if you've never used virtualization before,=20 it's definitely worth reading. > I'll download Gentoo in the meantime. I have never used it. I'm > getting the "minimal installation cd" from 29th september. > http://distfiles.gentoo.org/releases/x86/autobuilds/20150929/install-x8= 6-minimal-20150929.iso I meant by no means that you needed to use Gentoo, I only mentioned it=20 because it's what I use (which in turn is because that's what I use on=20 just about everything except stuff like the Raspberry Pi or the=20 BeagleBoard). If you just want to debug this and then be done with it,=20 I would actually advise against using Gentoo, it takes a lot of effort=20 to get a system up and running with it, and it's very involved to=20 maintain compared to Ubuntu. On the other hand though, if you are=20 willing to learn to use it, it's one of the most highly customizable=20 Linux distros out there, and can have noticeably better performance than = more generic distros (FWIW, it's also one of the last big distros that=20 doesn't force systemd on it's users by default). --------------ms050303050408040402030305 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 hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUxMDI5MjAwMTA1WjBPBgkq hkiG9w0BCQQxQgRAHM7ECLhoEHGMi7ARf4ByY79A+yx3YxQ9gY6u4NUdrNtzwwdMaQSwoGXO eMGjT7AxddPi6I6UQw2gAKWeXwaLSDBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxEt+DCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DAN BgkqhkiG9w0BAQEFAASCAgB04jysWnJU5ziHNImh+Q7ZmMpk6NQFHmaVWMlq0O7IIMwJYrOf OEsZJTRWMh3GMywex4TW+aiGyIvYVM64sszRonrxXrCNdI8OCFR4Pktu1ZGmv4QZhM+ii/nL ZwgnO7LluMbFNbpSjFzQ6P91jk+A5nd+gHNlSS/VezS/V3OnRnlFCCpGuS3vVKh1BqI8BUs7 Y7+8W9S9PRGIQE2WGFffk0Ds8HKFw4FwNy+Bk7xMVe6dGelAFDKOem4CxWJbjz+3uVGh9+CZ VyoMQiFlB3GVbOhVlEivSSs1GjL4ElUIEDQwBNxfzDF2I57Yaar8vvhSbfiDd5e64cbS8/wO tedjpp7oWbOGQcgV85fSucPjTeARilN5jSkGxxb/pmM6vxDBzZsricJBQIPy9pEk/j6yDc3B zzM8TJ0vlvqRO3lqNq4ogLDvRgWZGC44IrcfcAKJCsFxw5C01cvQg8EOBvok75bsHoF0YLGh sNymlWo04Z8z9l89jj7V6zwok0RIfL0Sxiomw9UhJwf8OrNderRhy8hJX7seyRMVtx4kotN/ Ts7lUSkdtPC+3p/Yy8W33JoH0or8t+9SR4eM1eey2KoAY6R3oDFUspwpb9AzyDcJVamF+74T ZVvemmEDySHrFLxQnIQB1mZBw0tgRmqiyTLxvvWbZZnoD8xyzPu/zeNb3gAAAAAAAA== --------------ms050303050408040402030305--