[mpich-discuss] MPI_Probe

[Nicolas Rosner]

Hi Jie,

The MPICH2 developers have already answered your questions, but may I
throw in an additional suggestion from an end user point of view?

> If in my process I have two threads, one of which issues the MPI_Probe call, will [...]

> In general I also want to understand what does MPI_Probe do [...]

I was wondering if perhaps you would be better off in such cases by
replacing "also" with "first"? Note that you don't need threads to
understand Probe, but you do need a firm grasp on the basics of Probe
to understand how it would behave in the presence of multithreading. I
mean this as just one possible example of a more general trend or
approach, of course (not really Probe-specific).

While mixing MPI with threads is possible and indeed quite common
nowadays, I think it's crucial to keep in mind that doing so
prematurely may be harmful to your learning curve. The complexities of
a scenario involving both are often considerably more than the sum of
their respective ones.

Personally, I'd ensure having understood any relevant MPI
functionality without threads first.

Hope this helps!

Nicolás