From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Anton Mitterer Subject: Re: some general questions on RAID Date: Sat, 06 Jul 2013 17:15:15 +0200 Message-ID: <1373123715.5217.27.camel@fermat.scientia.net> References: <1372962602.8716.56.camel@heisenberg.scientia.net> <51D5F22C.70007@turmel.org> <1373074400.10569.49.camel@fermat.scientia.net> <51D7DADA.50200@hardwarefreak.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="sha1"; protocol="application/x-pkcs7-signature"; boundary="=-vsh/LbojUC8NF9e8tOaY" Return-path: In-Reply-To: <51D7DADA.50200@hardwarefreak.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids --=-vsh/LbojUC8NF9e8tOaY Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sat, 2013-07-06 at 03:52 -0500, Stan Hoeppner wrote: > > Since even though you'd have one dmcrypt thread per disk now,... each o= f > > them would have to en/decrypt the "same" actual data for different > > devices... so while you have 4x threads... you need to do 4x > > en/decryption works. >=20 > This would only be true if using n-way mirroring. Ah yes... (as you already assumed) I missed the point with striping... ;) ... But also for RAID5/6 you shouldn't get n times the performance (when n is the number of disks), probably "only" about (n-1) times respectively (n-2) times, right? Cheers, Chris. --=-vsh/LbojUC8NF9e8tOaY Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIQ/jCCBXUw ggNdoAMCAQICAwEBgjANBgkqhkiG9w0BAQUFADBUMRQwEgYDVQQKEwtDQWNlcnQgSW5jLjEeMBwG A1UECxMVaHR0cDovL3d3dy5DQWNlcnQub3JnMRwwGgYDVQQDExNDQWNlcnQgQ2xhc3MgMyBSb290 MB4XDTEyMDcyMzE0NTY0NVoXDTE0MDcyMzE0NTY0NVowfDEhMB8GA1UEAxMYQ2hyaXN0b3BoIEFu dG9uIE1pdHRlcmVyMSQwIgYJKoZIhvcNAQkBFhVjYWxlc3R5b0BzY2llbnRpYS5uZXQxMTAvBgkq hkiG9w0BCQEWIm1haWxAY2hyaXN0b3BoLmFudG9uLm1pdHRlcmVyLm5hbWUwggEiMA0GCSqGSIb3 DQEBAQUAA4IBDwAwggEKAoIBAQCq/4X3Urm/IHCIYUyqPrBN6FZ2pmd8V5epPyDlveqtdYvLBLNy gP3G3KhGoCA4Jf49KYGmbqk+F7fVWcG1zcdwEx7itKJyj39nYf2HWXogxUSfKFptbOgpsTcEWuxg ka2EkJuErTvYbwCEKT7mn4v6ScuFBc3Q+Hswlt1jbqjczi+OxcU1skvxM5jGjzRwYPUsiHZJRkWp ogbbhNWZNbwXiMPln380TAlryRAr5UE0dSe1dg1qHhF6HSNKwaer0+Dcd/goL4XQhHxCAGZKfCK0 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