Hello,<br><br>In the context of my PhD research, I have been developing a run-time performance analyzer for MPI-based applications.<br>My
tool provides a controller process for each MPI task. In particular,
when a MPI job is started, a special wrapper script is generated that
first starts my controller processes and next each controller spawns an actual MPI task (that performs MPI_Init etc.). I use dynamic
instrumentation API (DynInst API) to control and instrument MPI tasks. <br><br>The point is I need to intercommunicate my controller
processes, in particular I need a point-to-point communication between
arbitrary pair of controllers. So it seems reasonable to take advantage
of MPI itself and use it for communication. However I am not sure what
would be the impact of calling MPI_Init and communicating from
controller processes taking into account both controllers and actual
MPI&nbsp; processes where started with the same mpirun invocation. Actually
I would need to assure that controllers have a separate MPI execution
enviroment while the application has another one.
<br><br>Any suggestions how to achive that? Obviously another option
is to use sockets to intercommunicate controllers, but having MPI this
seems to be overkill.<br><br>Thank you in advance for your help.<br><br>Regards,<br>
--Oleg<br><br><font size="1">PhD student, Universitat Autonoma de Barcelona, Spain<br><br></font>