[mythtv-users] Cheap SCSI scanners - was:The Bigger... Disk contest, Fall 2007 edition

[Brian Wood]

David Brodbeck wrote:
> On Oct 20, 2007, at 3:18 PM, Jay R. Ashworth wrote:
>> That datacenter buyers still use SCSI (and shortly, SAS) drives
>> exclusively, even over that 6:1 price disadvantage -- and the need to
>> sell it to PHBs -- tells me that the price differential exists for a
>> reason, or those guys would lose their jobs.
> 
> I just wonder if it exists for the same reason IBM systems used to  
> cost so much more than clones.  Is "no one ever regretted buying  
> SCSI" the modern version of "no one ever got fired for buying IBM?"

I suspect the "more drives per controller" was important, at least at
one time when giant drives were not available and controllers cost more.
It certainly made large RAID arrays easier to build.

Certainly before UDMA the transfer rates were very different.

Longer possible cable length was also significant, especially once LVD
came along. Ever see an external IDE case connected by a 6-foot cable?

Multiple LUNs made library systems possible, can you imagine trying to
make a 12-tape robot (or a 400 tape one) or a 10-drive CDROM jukebox
using IDE?

It is theoretically possible to have more than one controller on a scsi
bus, say two computers accessing the same scsi devices. Can you imagine
trying this with IDE? It wasn't done often, as there were huge issues,
but Solid State Logic and some other audio systems managed it (Roland?).

But most of these issues are of no concern to consumer users, so that
market went to IDE. It's just as silly to buy more than you need as to
buy less.

beww