From: Martin Quinson Date: Tue, 18 Sep 2018 17:55:49 +0000 (+0200) Subject: smpi tuto: finish the Lab0 X-Git-Tag: v3_21~78 X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/ed222923c9c49abf78f766c9ea38677a67328ca0?ds=sidebyside smpi tuto: finish the Lab0 --- diff --git a/docs/source/tuto_smpi.rst b/docs/source/tuto_smpi.rst index fe11f833c5..95116cbbd5 100644 --- a/docs/source/tuto_smpi.rst +++ b/docs/source/tuto_smpi.rst @@ -333,11 +333,11 @@ nodes from the ``cluster_crossbar.xml`` platform as follows: .. code-block:: shell - $ smpirun -np 16 -platform cluster_crossbar.xml -hostfile cluster_hostfile.txt ./roundtrip + $ smpirun -np 16 -platform cluster_crossbar.xml -hostfile cluster_hostfile ./roundtrip - The ``-np 16`` option, just like in regular MPI, specifies the number of MPI processes to use. -- The ``-hostfile cluster_hostfile.txt`` option, just like in regular +- The ``-hostfile cluster_hostfile`` option, just like in regular MPI, specifies the host file. If you omit this option, ``smpirun`` will deploy the application on the first machines of your platform. - The ``-platform cluster_crossbar.xml`` option, **which doesn't exist @@ -346,9 +346,12 @@ nodes from the ``cluster_crossbar.xml`` platform as follows: - At the end of the line, one finds the executable name and command-line arguments (if any -- roundtrip does not expect any arguments). - - -We will use following simple MPI program, roundtrip.c, in which the processes pass around a message and print the elpased time: - +Feel free to tweak the content of the XML platform file and the +prorgam to see the effect on the simulated execution time. Note that +the simulation accounts for realistic network protocol effects and MPI +implementation effects. As a result, you may see "unexpected behavior" +like in the real world (e.g., sending a message 1 byte larger may lead +to significant higher execution time). + .. LocalWords: SimGrid