Is software RAID 0 faster?

piwacet · Guru Joined: 30 Dec 2004 Posts: 486

HI. I'm currently on UDMA hard disks, but my motherboard supports SATA II, and I was thinking of getting 2 SATA II disks and re-installing Gentoo with / on those SATA II disks in a RAID 0 setup. I would use the kernel/software raid. Have people noticed a performance increase when doing RAID 0 (compared with SATA disks w/o RAID)? I've read mixed opinions in forums, and was just trying to figure out if it was worth it.

TIA!

Chaosite · Posted: Sun Jun 18, 2006 12:02 pm Post subject:

Simply put - Yes.

PaveQ · Posted: Sun Jun 18, 2006 12:21 pm Post subject:

Yes, and with doubled failure risk. :wink:

Taladar · Posted: Sun Jun 18, 2006 1:34 pm Post subject:

There is a reason RAID 0 is known as Kamikaze Raid (and it isn't the speed).

John R. Graham · Posted: Sun Jun 18, 2006 2:00 pm Post subject:

Concur on both points: software RAID 0 is both faster and (at least) 50% down in reliability. The speed comes from interleaving writes to the two drives, effectively doubling the write bandwidth. The solution to the reliability issue is to combine RAID 0 with one of RAID's common fault tolerant modes, typically RAID 1 or 5, resulting in a hybrid. It's called variously RAID 10, 1+0, 1/0, 50, 5+0, 5/0. It's not too practical for most workstation users because it requires a minimum of 4 drives for RAID 10 or 6 drives for RAID 50. Software RAID 10 is supported by the kernel.

- John

piwacet · Guru Joined: 30 Dec 2004 Posts: 486

Thanks for the input everybody!