idea for a universal disk interface

[Fred Cisin]

>>> 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" :-)
>
On Fri, 15 Apr 2022, Paul Koning wrote:
> "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.

50K would be bordering on extreme in the 1950s, and considered a LARGE 
buffer through the 1970s.  Certainly wasn't practical with less than 16 
bits of addressing.



> 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.