--- /dev/null
+/* Copyright (c) 2010-2020. The SimGrid Team. All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "mpi.h"
+#include "simgrid/s4u.hpp"
+
+#include <stdio.h> /* snprintf */
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(msg_test, "Messages specific for this msg example");
+
+static void master(std::vector<std::string> args)
+{
+ xbt_assert(args.size() > 4, "The master function expects at least 3 arguments");
+
+ long tasks_count = std::stol(args[1]);
+ double compute_cost = std::stod(args[2]);
+ double communication_cost = std::stod(args[3]);
+ std::vector<simgrid::s4u::Mailbox*> workers;
+ for (unsigned int i = 4; i < args.size(); i++)
+ workers.push_back(simgrid::s4u::Mailbox::by_name(args[i]));
+
+ XBT_INFO("Got %zu workers and %ld tasks to process", workers.size(), tasks_count);
+
+ for (int i = 0; i < tasks_count; i++) { /* For each task to be executed: */
+ /* - Select a worker in a round-robin way */
+ simgrid::s4u::Mailbox* mailbox = workers[i % workers.size()];
+
+ /* - Send the computation cost to that worker */
+ XBT_INFO("Sending task %d of %ld to mailbox '%s'", i, tasks_count, mailbox->get_cname());
+ mailbox->put(new double(compute_cost), communication_cost);
+ }
+
+ XBT_INFO("All tasks have been dispatched. Request all workers to stop.");
+ for (unsigned int i = 0; i < workers.size(); i++) {
+ /* The workers stop when receiving a negative compute_cost */
+ simgrid::s4u::Mailbox* mailbox = workers[i % workers.size()];
+
+ mailbox->put(new double(-1.0), 0);
+ }
+}
+
+static void worker(std::vector<std::string> args)
+{
+ xbt_assert(args.size() == 1, "The worker expects no argument");
+
+ const simgrid::s4u::Host* my_host = simgrid::s4u::this_actor::get_host();
+ simgrid::s4u::Mailbox* mailbox = simgrid::s4u::Mailbox::by_name(my_host->get_name());
+
+ double compute_cost;
+ do {
+ const double* msg = static_cast<double*>(mailbox->get());
+ compute_cost = *msg;
+ delete msg;
+
+ if (compute_cost > 0) /* If compute_cost is valid, execute a computation of that cost */
+ simgrid::s4u::this_actor::execute(compute_cost);
+
+ } while (compute_cost > 0); /* Stop when receiving an invalid compute_cost */
+
+ XBT_INFO("Exiting now.");
+}
+
+static int master_mpi(int argc, char* argv[])
+{
+ MPI_Init(&argc, &argv);
+
+ int rank;
+ MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+ XBT_INFO("here for rank %d", rank);
+ int test[1000] = {rank};
+ if (rank == 0)
+ MPI_Send(&test, 1000, MPI_INT, 1, 1, MPI_COMM_WORLD);
+ else
+ MPI_Recv(&test, 1000, MPI_INT, 0, 1, MPI_COMM_WORLD, MPI_STATUSES_IGNORE);
+
+ XBT_INFO("After comm %d", rank);
+ MPI_Finalize();
+
+ XBT_INFO("After finalize %d %d", rank, test[0]);
+ return 0;
+}
+
+static int alltoall_mpi(int argc, char* argv[])
+{
+ MPI_Init(&argc, &argv);
+
+ int rank;
+ int size;
+ MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+ MPI_Comm_size(MPI_COMM_WORLD, &size);
+ XBT_INFO("alltoall for rank %d", rank);
+ int* out = new int[1000 * size];
+ int* in = new int[1000 * size];
+ MPI_Alltoall(out, 1000, MPI_INT, in, 1000, MPI_INT, MPI_COMM_WORLD);
+
+ XBT_INFO("after alltoall %d", rank);
+ delete[] out;
+ delete[] in;
+ MPI_Finalize();
+ return 0;
+}
+
+int main(int argc, char* argv[])
+{
+ simgrid::s4u::Engine e(&argc, argv);
+
+ SMPI_init();
+
+ xbt_assert(argc > 2,
+ "Usage: %s platform_file deployment_file\n"
+ "\nexample: %s msg_platform.xml msg_deployment.xml\n",
+ argv[0], argv[0]);
+
+ e.load_platform(argv[1]);
+
+ e.register_function("master", master);
+ e.register_function("worker", worker);
+ // launch two MPI applications as well, one using master_mpi function as main on 2 nodes
+ SMPI_app_instance_register("master_mpi", master_mpi, 2);
+ // the second performing an alltoall on 4 nodes
+ SMPI_app_instance_register("alltoall_mpi", alltoall_mpi, 4);
+ e.load_deployment(argv[2]);
+
+ e.run();
+
+ XBT_INFO("Simulation time %g", e.get_clock());
+
+ SMPI_finalize();
+ return 0;
+}
