[Beowulf] cluster softwares supporting parallel CFD computing

Geoff Jacobs gdjacobs at gmail.com
Thu Sep 14 19:16:42 PDT 2006


Patrick Geoffray wrote:
<snip>
> Alas, people use blocking calls in general because
> they are lazy (50%), they don't know (40%) or they don't care (10%).

They're writing around an unpatched race condition in MPICH 1.2.2.

> There is also the chicken and egg problem: nobody really tried to
> overlap, so MPI implementations didn't bother to support it, so you
> could not really overlap, so nobody really tried. However, some MPI
> implementations can overlap today and some applications can leverage it.
> 
> The best and only way to have MPI applications do the right thing would
> be to remove all blocking calls in MPI :-)

For those applications which organizationally cannot make use of
simultaneous message passing and computation, blocking sends and
receives are a nice convenience. If it makes you happy, implement
blocking sends and receives with non-blocking ones.

-- 
Geoffrey D. Jacobs

Go to the Chinese Restaurant,
Order the Special



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