From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brown Subject: Re: RAID-10 with mixed block size HDDs Date: Fri, 29 Mar 2013 14:22:10 +0100 Message-ID: <51559582.7000406@hesbynett.no> References: <1036112.4.1364562908784.JavaMail.root@zimbra> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1036112.4.1364562908784.JavaMail.root@zimbra> Sender: linux-raid-owner@vger.kernel.org To: Roy Sigurd Karlsbakk Cc: Piergiorgio Sartor , linux-raid@vger.kernel.org List-Id: linux-raid.ids On 29/03/13 14:15, Roy Sigurd Karlsbakk wrote: >>>> Hi all, >>>> >>>> I've a two disk RAID-10 (far 2, I guess). >>> >>> You can't grow a RAID-10=E2=80=A6 >> >> I know, I've to replace a disk, non add. > > I just don't understand why anyone would create a two-drive RAID-10, > losing the flexibility of a mirror, and gaining nothing (since it's > only on two drives) > With "far" layout, linux RAID-10 on two harddisks will give you the=20 safety of RAID-1 mirroring with /faster/ than RAID-0 speeds on reads.=20 (Writes are often a little slower than standard RAID-1 due to more head= =20 movement, but slow writes can be buffered, while fast reads mean a=20 faster machine.) Yes, you lose a bit of flexibility, and it would be very nice if RAID-1= 0=20 could be re-shaped, grown, etc. But for a desktop system in particular= ,=20 RAID-10,far2 is the best you can get for two disks. -- 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