MPI's Socket Communication Integration Test on 'local' system for the TVB-NEST/launcher application

[ringleschavez]

Aspect	Detail
Summary	The integration-test of the MPI's Socket communication approach for the TVB-NEST/launcher code.
Task Area	Research, Development
Assignee	@ringleschavez
Information	Exclusively Point-to-Point approach must be tested, i.e. one-to-one
Prerequisites
Dependencies	#74 #82

Summary

Having worked on the TVB-NEST-demo on "local" VM, there were found different issues related to the MPI's "socket-style" communication approach.

In order to become aware of the scope and limitations about of the mentioned approach, the Integration-Test on TVB-NEST/launcher will allow to have a set of test showing how the MPI's Socket-Style communication approach could be used in the Co-Simulation Framework.

Tasks

• [x] Designing and developing the Integration-Test XML Configuration Files
• [x] Developing the Socket-Server python scripts for the Integration-Test used by the TVB-NEST/launcher application
• [x] Implementing the Socket-Client python scripts for the Integration-Test used by the TVB-NEST/launcher application
• [x] Making up the Integration-Test and performing preliminary test on 'local' system (VM).
• [x] Fixing found issues
• [x] Tidying up the configuration files and python scripts.
• [x] Performing the pull-request.

Requirements

• A 'local' (VM) with a MPI library and MPI4PY able to compile and run in order to perform preliminary tests of the MPI's Socket-Style communication approach.

Acceptance criteria

• Integration-Test for the TVB-NEST/launcher application demonstrating the usage of the MPI's Socket-Style communication functional to the Co-Simulation Framework.

Remarks

• It would be worth to perform tests by using MPICH and OpenMPI.
• Similarly, testing the blocking and non-blocking calls could be a different Integration-Test.
• Finally, both communication method could be tested as well, namely, "memory buffer communication" (Comm.Send, Comm.Recv) and "Python objects communication" (Comm.send, Comm.recv).

• References:

  [1] https://mpi4py.readthedocs.io/en/stable/overview.html#collective-communications [2] https://mpi4py.readthedocs.io/en/stable/tutorial.html#point-to-point-communication [3] https://www.hlrs.de/about-us/media-publications/teaching-and-training-material/MPI-course-material/ [4] https://pages.tacc.utexas.edu/~eijkhout/pcse/html/mpi-proc.html#Socket-stylecommunications [5] https://web.corral.tacc.utexas.edu/CompEdu/pdf/pcse/

[ringleschavez]

Former list of task until 2022-02-27: Creating a Socket-Server program Creating a Socket-Client program Testing MPI Socket-Server on receive mode Testing MPI Socket-Server on send mode Testing MPI Socket-Server on mixed mode (receive/send) Testing MPI Socket-Server on 1-to-n approach Integration-Test Configuration Files Python scripts for the Integration-Test used by the TVB-NEST/launcher application

[ringleschavez]

Message Checking

Examples how MPI.Comm.Probe could be used for checking received messages beforehand.

https://github.com/mpi4py/mpi4py/blob/master/test/test_p2p_buf.py https://github.com/mpi4py/mpi4py/blob/master/demo/mpi-ref-v1/ex-2.29.py

[ringleschavez]

https://github.com/multiscale-cosim/TVB-NEST/pull/21/commits/bac545e9952028c3dde7472381446fb63764a4b6

[ringleschavez]

Important information about the OpenMPI rendezvous server ompi-server: issue # 6916 by rhc54

[ringleschavez]

Important information about the OpenMPI rendezvous server ompi-server: issue # 6916 by rhc54