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RE: rewriting CSP processes

Barry, et al.

> -----Original Message-----
> From:	B.M. Cook [SMTP:b.m.cook@xxxxxxxxxxxxxx]
> Sent:	Wednesday, September 27, 2000 8:00 AM
> To:	John.Campbell@xxxxxxxxxxxxxx
> Cc:	java-threads@xxxxxxxxx; occam-com@xxxxxxxxx
> Subject:	Re: rewriting CSP processes
> John, et al.
> > ...The words around the mathematics
> > talk about "events" being instantaneous transactions that
> > are handshaken ...    Handshaking 
> > protocols don't execute in zero time, and signals don't
> > propagate instantly.  
> Clocked logic only changes state on clock edges, it is not possible to
> distinguish time intervals less than a clock cycle time. ...
>  With real delays from propagating signals we increase the
> clock period (slow the system down) until the above holds. 
	But there is a price for such convenience...the performance of
	the whole system is at the mercy of the longest logic chain.

> (Aside, the
> maximum clock rate for things like processors is determined by propagation
> delays across the silicon. A proposed solution is to divide the chip into
> local clock domains with message passing between them - and the world
> re-invents transputers!)
	Well... That *is* the kind of thing CSP is good for!

> It is *very* much harder to synchronize logic with multiple clocks and
> other
> realities.
	Shouldn't it be possible to automatically deal with such issues?