> On Aug 11, 2015, at 12:20 PM, Chuck Guzis <[email protected]> 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.
paul
