Re: forall and do loop

OK, it may simply be that I misunderstood your emphasis, and anyway the kind
of stuff I develop is rarely running within one shared memory box. It's
just that whenever I hear the contention that shared memory programming,
and in particular OpenMP, is a simpler model than message passing I find
that I can not agree, after all one just has private variables while the
other has both private and public. But that, yet again, is quite likely a
function of my experience and the problems I am trying to solve,

Ian

The model itself may not be simpler, but definitely OpenMP is much
simpler to use. I've been able to learn OpenMP and successfully
parallelize my first program within a few hours.
For OpenMP, I just code up a "normal" (serial) program, barely
considering the future parallelism, debug, then throw directives here
and there, and it normally works on the first try.
Running on 2 CPUs usually gives 2x speed-up, running on 8 CPUs only
rarely approaches 8x speed-up, but it scales at least to some extent
with very few extra work.

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