From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: What's the typical RAID10 setup? Date: Fri, 04 Feb 2011 02:27:38 -0600 Message-ID: <4D4BB87A.30800@hardwarefreak.com> References: <20110131192858.GD27952@www2.open-std.org> <4D4718E1.9040607@hardwarefreak.com> <20110131203725.GB2283@www2.open-std.org> <4D475AB5.10600@hardwarefreak.com> <20110203110428.GA26762@www2.open-std.org> <4D4B3DAE.3070502@hardwarefreak.com> <20110204070613.GA3788@www2.open-std.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20110204070613.GA3788@www2.open-std.org> Sender: linux-raid-owner@vger.kernel.org To: =?ISO-8859-1?Q?Keld_J=F8rn_Simonsen?= Cc: Jon Nelson , =?ISO-8859-1?Q?Mathias_?= =?ISO-8859-1?Q?Bur=E9n?= , Roberto Spadim , Denis , Linux-RAID List-Id: linux-raid.ids Keld J=F8rn Simonsen put forth on 2/4/2011 1:06 AM: > Well RAID1+0 is not the best combination available. I would argue tha= t > raid10,f2 is significantly better in a number of areas. I'd guess Linux software RAID would be lucky to have 1% of RAID deploym= ents worldwide--very lucky. The other 99%+ are HBA RAID or SAN/NAS "applian= ces" most often using custom embedded RTOS with the RAID code written in assemble= r, especially in the case of the HBAs. For everything not Linux mdraid, R= AID 10 (aka 1+0) is king of the hill, and has been for 15 years+ >> Something smells bad here. Does one of the RAID companies own a pat= ent or >> trademark on "RAID 10"? I'll look into this. It just doesn't make = any sense >> for RAID 10 to be omitted from the SNIA DDF but to be referenced in = the manner >> it is. >=20 > It looks like they do define all major basic RAID disk layouts. (exce= pt > raid10,f2 of cause) . RAID1+0 is a derived format, maybe that is out = of > scope of the DDF standard. "A secondary virtual disk is a VD configured using hybrid RAID levels l= ike RAID10 or RAID50. Its elements are BVDs." So apparently their Disk Data Format specification doesn't include hybr= id RAID levels. This makes sense, as the _on disk_ layout of RAID 10 is identi= cal to RAID 1. We apparently need to be looking for other SNIA documents to find their definition of RAID 10. That is what started us down this tunnel isn't = it? We're so deep now there's no light and I can't see the path behind me a= nymore. ;) --=20 Stan -- 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