-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Clayton Milos wrote:
> If you want awesome performance and reliability the real way to go is > RAID10 (or more correctly RAID 0+1). RAID10 and RAID0+1 are very different beasts. RAID10 is the best choice for a read/write intensive f/s with valuable data, exactly what you need to support a RDBMS. It is built by pairing up all of the drives as RAID1 mirrors[*] and then creating a RAID0 stripe across all of the mirrors. It's the least economical RAID setup, giving you a usable space which is 50% of the total raw disk space, but it is the most resilient -- potentially being able to survive half of the drives failing -- and much the best performing of the RAID types. RAID0+1 on the other hand is what you give to someone you don't like very much. In this case, you divide the disks into two equal sets, create a RAID0 stripe over each set and then a RAID1 mirror over the stripes. It has the /delightful/ feature that failure of any one drive immediately puts half of the available disks out of action: ie it is *less* resilient than any other RAID setup (other than a RAID0 stripe over all the drives). Space economy-wise it's exactly like RAID10 and performance characteristics are pretty similar to RAID10, leading to the obvious conclusion: use RAID10 instead. Cheers, Matthew [*] The correctly paranoid sysadmin will of course ensure that each of the disks in those pairs hangs off a different bus, comes from a different manufacturing batch and is preferably connected to a different controller and with different, independent power supplies. Or, in extreme cases, that each half of the mirrors are in completely different datacenters. - -- Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard Flat 3 PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate Kent, CT11 9PW -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFGxqmh8Mjk52CukIwRCPvyAJ4k/POTK9Moqu80nV9TKHZqLIC5ngCfYEd4 oiV2MAAiFIXcNSTSiCM4D6M= =GDZN -----END PGP SIGNATURE----- _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"