The differences I've seen between "raid edition" drives and regular drives are:
* Dramatically better vibration resistance. If you are going to bolt a drive or two into a desktop it doesn't matter so much. If you are going to plug a drive into a 16 bay enclosure or even into a 1U node with a ton of fast fans you might well see a large performance difference because of the vibration. The specification sheets do reflect this btw, I assume this is mostly lower density platters and stronger motors for positioning the heads. This is especially noticeable on the consumer drives with the higher density platters (375-500GB per platters). I've seen consumer drives that manage 120MB/sec drop to a noisy fluctuation between 18-30 MB/sec because of vibration * Consumer drives (at least the non-media ones) often have occasional thermal recalibrations. This seems better these days, but last thing you want is a recal triggering a degraded array. * Consumer drives will go to heroic efforts to read a bad sector, exactly the opposite of what you want in a RAID drive. In a RAID it's better to fail and yell bloody murder... especially when the rereading a sector a bunch causes the raid to time out and drop the disk. Of course manufactures claim various things about error rates per billion bits, designed duty cycles (40 hours a week vs 24/7), improve temperature envelops, and related. Alas while this is nice to hear I've not seen any direct results because of it. As an example, 500GB wd caviar $64.99, 500GB WD RE3 $89.99. IMO if you are building a raid or heavily used 1U with a ton of fans the extra $25 is worth it. _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
