Re: idea for a universal disk interface

[Paul Koning via cctalk]

> On Apr 15, 2022, at 6:54 PM, Fred Cisin via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> On Thu, 14 Apr 2022, Tom Gardner via cctalk wrote:
>> This was the approach IBM used in it's first RAMAC RAID where I think they 
>> had to buffer a whole cylinder but that was many generations ago
> 
> (my copy of the specs may not be exact):
> Buffering a whole cylinder, or a whole surface, of the RAMAC was no big deal.
> One hundred surfaces (52 platters, but not using bottom of bottommost nor top 
> of topmost) totalling to 5 million 6 bit characters.
> 
> That's 50,000 characters per surface.
> OR 50,000 characters per cylinder
> ("square geometry" :-)

"Was" as in "back in the day"?  50k characters would have been quiet a large 
memory in the 1950s.  And for an I/O device, any kind of buffer is not 
necessarily all that useful.

What does make sense is a track buffer in drum memory machines, as found for 
example in the Dutch ARMAC, where the first implementation of the famous 
"shortest path" algorithm was first implemented.

        paul