And speaking of ALGOL

Paul Koning paulkoning at
Tue Aug 11 12:59:28 CDT 2015

> On Aug 11, 2015, at 12:20 PM, Chuck Guzis <cclist at> wrote:
> ...
>> I suspect part of the reason is that Algol wasn’t all that popular in
>> the USA even if its heyday. Add to that the fact that most computer
>> designers weren’t all that skilled in software. And finally, as the
>> RISC experience has shown, it isn’t really worth it.
> ...
> What RISC does demand is a fast memory system.  The 6600 had 1 usec memory interleaved 10 ways, so it could issue a read or write every machine cycle (100 nsec).  Without that, the 6600 could well have been a real dog.

Every machine needs a fast memory system.  CISC machines just as much, after all the number of memory references per operation of a given kind doesn’t depend on the sort of CPU architecture you use.  All that changes is whether the cycles are issued by regular machine code, or micro-engine actions.

A full-up 6600 is 32 way interleaved; half size you get 16 way interleaving.  Once nice benefit is that context switching takes only a few microseconds, because the exchange jump would swap current and new context at memory speed: 16 words issued at 100 ns intervals once the operation gets moving.


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