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Brians256 · 06-18-2007, 06:29 AM

Older U-SCSI isn't bad, it merely suffers from techno-age. There are two consequences for being out of date, though. First, the parts get more expensive than they used to be instead of getting cheaper. Second, there exists another standard that is "better" (in this case, faster).

If you want to have higher performance than 320MB SCSI, you can get faster throughput by using SATA array. The newer SATA drives are faster on latency and throughput, and the cmd queuing and other SCSI advantages aren't quite good enough to catch up. Also, the SATA-2 standard is 300Mbps per drive, not an aggregate 320Mbps per cable of up to 7 drives.

If you want more reliability, then (to me) having RAID-6 with cheap and (most importantly) easily available drives is wonderful. The key here is cheap and easily available. The older SCSI drives just aren't as easy to find. Being able to get a replacement drive for my array within 40 minutes is very convenient (local stores carry SATA drives but no one locally carries SCSI drives any more). No standard can prevent failures, but RAID-6 makes failures very unlikely to be serious and SATA makes the failures easy to deal with.

Those are my opinions. Real IT people will certainly have more info and may have different criteria.

06-18-2007, 06:29 AM	#15
Brians256 Pro/Staff Join Date: Oct 2001 Location: Klamath Falls, OR Posts: 1,439	Re: picked up a free computer Older U-SCSI isn't bad, it merely suffers from techno-age. There are two consequences for being out of date, though. First, the parts get more expensive than they used to be instead of getting cheaper. Second, there exists another standard that is "better" (in this case, faster). If you want to have higher performance than 320MB SCSI, you can get faster throughput by using SATA array. The newer SATA drives are faster on latency and throughput, and the cmd queuing and other SCSI advantages aren't quite good enough to catch up. Also, the SATA-2 standard is 300Mbps per drive, not an aggregate 320Mbps per cable of up to 7 drives. If you want more reliability, then (to me) having RAID-6 with cheap and (most importantly) easily available drives is wonderful. The key here is cheap and easily available. The older SCSI drives just aren't as easy to find. Being able to get a replacement drive for my array within 40 minutes is very convenient (local stores carry SATA drives but no one locally carries SCSI drives any more). No standard can prevent failures, but RAID-6 makes failures very unlikely to be serious and SATA makes the failures easy to deal with. Those are my opinions. Real IT people will certainly have more info and may have different criteria.