[Zope] RE: offtopic RE: [Zope] HD

[Alexander Staubo]

> > IDE/ATAPI drive? Unless money is really tight, don't go for 
> anything but
> Absolutly right ;)
> Only the really tight isn't appropiate anymore nowadays :(, I've just
> calculated the ratio for big discs, and it comes to 2.73 :(
> 
> 36400MB IBM DRHS-336400LVD                     2.85 cent/MB
> 25000MB IBM DJNA-352500 Janus                  1.04 cent/MB
> 
> I know, you get completely two different kinds of discs, but both
> basically store data. 

Well, I'm not even sure the comparison was worthwhile (fyi, floppy disks
basically store data, too ;).

Without wanting to go into an extremely detailed, esoteric discussion...
[I tried to match your model numbers with the IBM catalogue, I hope I
got this right]

DRHS-336400LVD (IBM Ultrastar 36XP):
  36.4GB 
  U2W Low-Voltage Differential 
  7200RPM?, 7.5 ms avg seek time
  19.7MB/sec sustained transfer rate
  4.0MB cache
  SCSI controller on-deck

DJNA-352500 (IBM Desktar 25GP)
  25GB
  Ultra DMA/66
  5400RPM, 8.5ms avg seek time
  15.5MB/sec sustained transfer rate
  2.0MB cache
  Brainless

> > SCSI. SCSI is a much more flexible solution, and generally 
> faster, less
> > CPU-intensive, and more compatible.
> That is not really true. Well done DMA is about the same 
> level than SCSI,

If you have one disk or two disks on separate chains -- yes. Now,
exactly how realistic is that? Not to mention you can't have more than
four devices in total, two of which can never be accessed concurrently
because of IDE design limitations. You can chuck in more controllers,
but you have only so many PCI slots. ;)  And never mind the fact that
ATA66 pushes 66MB/sec max, whereas U2W now is at 80MB/sec with standard
SCA-2 cabling, up to 200MB/sec with FCAL. And never mind the fact that
they simply don't make really fast ATAPI drives. ;)

-- 
Alexander Staubo             http://www.mop.no/~alex/
"QED?" said Russell.
"It's Latin," said Morgan. "It means, 'So there you bastard'."
--Robert Rankin, _Nostramadus Ate My Hamster_