[computer-go] MPI vs. threads

[Darren Cook]

>>> Can MPI be as quick as threads on a 2- or 4-core single
>>> machine?
> 
> no, but I think you are worried about something that is such a a small
> percentage of compute time that I doubt that it is significant for a Go
> program.

A random playout might complete in 10 microseconds. Is thread or MPI
overhead going to be say less than 5% of that? If so, yes, I probably
don't care.

>> The usage of MPI that I've seen required explicit population of
>> (user-defined) communication structures that get copied in the process
>> of doing an MPI call.
> 
> This is true and something we tried to put some wrappers around to
> simplify, but this underlying fact could not be removed. 

Have you seen Boost.MPI?
http://www.generic-programming.org/~dgregor/boost.mpi/doc/mpi/tutorial.html

Is it successfully hiding the issue you are talking about?

(MPI was accepted into boost, but isn't in boost 1.34, and I doubt we'll
see 1.35 released for over 6 months; it seems to have a non-trivial
install and build stage...)

Darren