From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keld =?iso-8859-1?Q?J=F8rn?= Simonsen Subject: Re: What's the typical RAID10 setup? Date: Mon, 31 Jan 2011 21:37:25 +0100 Message-ID: <20110131203725.GB2283@www2.open-std.org> References: <20110131152151.GD7861@cthulhu.home.robinhill.me.uk> <20110131192858.GD27952@www2.open-std.org> <4D4718E1.9040607@hardwarefreak.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <4D4718E1.9040607@hardwarefreak.com> Sender: linux-raid-owner@vger.kernel.org To: Stan Hoeppner Cc: Keld =?iso-8859-1?Q?J=F8rn?= Simonsen , Roberto Spadim , Denis , Linux-RAID List-Id: linux-raid.ids On Mon, Jan 31, 2011 at 02:17:37PM -0600, Stan Hoeppner wrote: > Keld J=F8rn Simonsen put forth on 1/31/2011 1:28 PM: > > Top-posting... > >=20 > > How is the raid0+1 problem of only 33 % survival for 2 disk with RA= ID10? > >=20 > > I know for RAID10,F2 the implementation in Linux MD is bad. > > It is only 33 % survival, while it with a probably minor fix could = be 66%. > >=20 > > But how with RAID10,n2 and RAID10,o2? >=20 > I don't care what Neil or anyone says, these "layouts" are _NOT_ RAID= 10. If > you want to discuss RAID 10, please leave these non-standard Frankens= tein > "layouts" out of the discussion. Including them only muddies things = unnecessarily. Please keep terminology clean, and non-ambigeous. Please refer to the old term RAID10 as RAID1+0, which is also the original and more precise term for that concept of multilevel RAID. RAID10 on this list refers to the RAID10 modules of the Linux kernel. I can concurr that this may be a somewhat misleading term, as it is easily confused with the popular understanding of RAID10, meaning RAID1+0. And I see Linux RAID10 as a family of RAID1 layouts. Indeed RAID10,n2 is almost the same as normal RAID1, and RAID10,o2 is an implementation of a specific layout of the RAID1 standard. RAID10,f2 could easily also be seen as a specific RAID1 layout. But that is the naming of terms that we have to deal with on this Linux kernel list for the RAID modules. best regards Keld -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html