Raid Advice

Deonilin · 28 Jun 2008 at 14:31

Hi,

I’m looking for some advice for a new rig which is currently on the cards. In previous builds I have always gone with a standard setup but after research I now have a basic understanding of raid types, for my purpose raid0 is the most suitable. When it comes to performance is it more logical to increase the number of drives say 6x80Gb instead of a 2x250Gb drive configuration.

I do have separate backups in place, NAS and external HDD, but is drive failure a problem with raid – drives tend to be more prone to failier?

Thanks

Duncan

Greenlizard0 · 28 Jun 2008 at 15:21

I'm not sure whether individual drives are more prone to fail by being in a RAID array, however if you strip that many when one fails, the whole array fails.

rpstewart · 28 Jun 2008 at 15:33

Deonilin said:
When it comes to performance is it more logical to increase the number of drives say 6x80Gb instead of a 2x250Gb drive configuration.

Not really. As you increase the number of disks in the array the latency will increase as well which will affect performance. Then you have to consider the speed of the individual drives, these days 80Gb 7200rpm disks are pretty slow to the point that a pair in RAID0 will struggle to out perform a single 250Gb drive. As a result 6 x 80Gb isn't going to be a lot faster than 2 x 250Gb.

Deonilin · 28 Jun 2008 at 15:38

Thanks great help

lopkinfop · 28 Jun 2008 at 16:36

also the limiting factor with a large number of drives in raid would be the controller

Namistai · 28 Jun 2008 at 20:46

I guess that the more drives you have in a RAID0 array, the more risk you have of failure. More components to go wrong!

Cob · 28 Jun 2008 at 22:00

Yeah. But then each disk is only being accessed half as long if using two disks, a third as long if using 3 disks etc etc.

AbsenceJam · 28 Jun 2008 at 22:13

Cob said:
Yeah. But then each disk is only being accessed half as long if using two disks, a third as long if using 3 disks etc etc.

FireShadow who doesn't seem to know a thing posted that theory in another topic, well not just the theory the clear statement that you should never use single disks as RAID0 is much safer, and RAID5/6 etc are crap apparently.... It's complete rubbish.
With RAID0 all your disks are in constant use, with separate disks your OS disk is in constant use but other disks aren't necessarily being used so it's better for them. It's putting wear on all drives vs. more wear on one (given normal use).
And since you have the same capacity either way if you constantly read/write data with either option the wear per disk would be just the same.

RAID0 is added risk for speed, nothing more.