Re: Low Budget Performance

On Tue, Oct 29, 2002 at 10:43:33AM -0800, eric soroos wrote:
> Is a scsi system that much better? Looking at prices, scsi is 1/2
> the capacity and double the price for the 80 gig 7200rpm ide vs 36
> gig 10k rpm scsi. Assuming that I'll never run out of space before
> running out of performance, I can dedicate 2x the number of ide
> drives to the problem.

SCSI is dramatically better at using the interface.  It is much
smarter about, for instance, handling multiple disks at the same
time; and it requires less attention from the CPU.

That said, if you have enough high speed IDE controllers and disks,
you'll probably beat an older SCSI system.  And you can't beat the
price/performance of IDE RAID.  We use it for some applications.

Note also that you get better RAID controllers from SCSI vendors,
just because it's the official high speed offering.  The Promise IDE
RAID is nice, but it sure isn't as fast as the latest SCSI RAID
controllers.  (We have also found that there's some overhead in the
IDE RAID.  It was better under FreeBSD than I'm now experiencing
under Linux.  But that might just be my prejudices showing!)

A
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