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From: Greg Lindahl (lindahl_at_[hidden])
Date: 2005-10-12 12:42:17

On Wed, Oct 12, 2005 at 12:05:13PM +0100, Ashley Pittman wrote:

> Thirdly is the performance issue, any MPI vendor worth his salt tries
> very hard to reduce the number of function calls and library's between
> the application and the network, adding another one is a step in the
> wrong direction. This may not matter so much for ethernet clusters but
> certainly for some people the software stack accounts for a surprising
> percentage of "network" latency.

OK, so that's a new item for the Technical List Of Things To Do:
measure the overhead. I suspect it'll turn out to be small, even for
interconnects that care about 50 nanoseconds of additional overhead.

-- greg