Reproducing old machines with newer technology

Chuck Guzis cclist at
Sun Jul 19 00:26:36 CDT 2015

On 07/18/2015 09:06 PM, Mike Stein wrote:

> I always wondered which was more efficient, multiplexing among
> essentially complete 'computers per user' sharing a common I/O 'channel'
> or swapping processes and memory banks...

Well, the multiplexing (via hardware) memory among a single processor 
did have the advantage that it was possible to hang a single "processor" 
without taking down the whole shebang--you could simply label the 
processor as unavailable in the processor pool.  Believe me, when 
debugging PPU programs that was very handy--hang a PPU, try again, 
without rebooting the system.

Later versions of the Cyber (e.g. 170/180) actually used separate 
completely autonomous processors.


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