-/* Copyright (c) 2017. The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2017-2018. 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. */
+/* Parallel tasks are convenient abstractions of parallel computational kernels that span over several machines.
+ * To create a new one, you have to provide several things:
+ * - a vector of hosts on which the task will execute
+ * - a vector of values, the amount of computation for each of the hosts (in flops)
+ * - a matrix of values, the amount of communication between each pair of hosts (in bytes)
+ *
+ * Each of these operation will be processed at the same relative speed.
+ * This means that at some point in time, all sub-executions and all sub-communications will be at 20% of completion.
+ * Also, they will all complete at the exact same time.
+ *
+ * This is obviously a simplistic abstraction, but this is very handful in a large amount of situations.
+ *
+ * Please note that you must have the LV07 platform model enabled to use such constructs.
+ */
+
#include "simgrid/plugins/energy.h"
#include <simgrid/s4u.hpp>
-#include <xbt/ex.hpp>
-#include <xbt/log.h>
XBT_LOG_NEW_DEFAULT_CATEGORY(s4u_energyptask, "Messages specific for this s4u example");
static void runner()
{
/* Retrieve the list of all hosts as an array of hosts */
- int hosts_count = sg_host_count();
- simgrid::s4u::Host** hosts = sg_host_list();
+ std::vector<simgrid::s4u::Host*> hosts = simgrid::s4u::Engine::get_instance()->get_all_hosts();
+ int hosts_count = hosts.size();
XBT_INFO("First, build a classical parallel task, with 1 Gflop to execute on each node, "
"and 10MB to exchange between each pair");
- double* computation_amounts = new double[hosts_count]();
- double* communication_amounts = new double[hosts_count * hosts_count]();
- for (int i = 0; i < hosts_count; i++)
- computation_amounts[i] = 1e9; // 1 Gflop
+ std::vector<double> computation_amounts;
+ std::vector<double> communication_amounts;
+ /* ------[ test 1 ]----------------- */
+ computation_amounts.assign(hosts.size(), 1e9 /*1Gflop*/);
+ communication_amounts.assign(hosts.size() * hosts.size(), 0);
for (int i = 0; i < hosts_count; i++)
for (int j = i + 1; j < hosts_count; j++)
communication_amounts[i * hosts_count + j] = 1e7; // 10 MB
- simgrid::s4u::this_actor::parallel_execute(hosts_count, hosts, computation_amounts, communication_amounts);
+ simgrid::s4u::this_actor::parallel_execute(hosts, computation_amounts, communication_amounts);
+ /* ------[ test 2 ]----------------- */
XBT_INFO("We can do the same with a timeout of one second enabled.");
- computation_amounts = new double[hosts_count]();
- communication_amounts = new double[hosts_count * hosts_count]();
-
- for (int i = 0; i < hosts_count; i++)
- computation_amounts[i] = 1e9; // 1 Gflop
-
+ computation_amounts.assign(hosts.size(), 1e9 /*1Gflop*/);
+ communication_amounts.assign(hosts.size() * hosts.size(), 0);
for (int i = 0; i < hosts_count; i++)
for (int j = i + 1; j < hosts_count; j++)
communication_amounts[i * hosts_count + j] = 1e7; // 10 MB
try {
- simgrid::s4u::this_actor::parallel_execute(hosts_count, hosts, computation_amounts, communication_amounts,
+ simgrid::s4u::this_actor::parallel_execute(hosts, computation_amounts, communication_amounts,
1.0 /* timeout (in seconds)*/);
XBT_WARN("Woops, this did not timeout as expected... Please report that bug.");
} catch (xbt_ex& e) {
XBT_DEBUG("Caught expected exception: %s", e.what());
}
+ /* ------[ test 3 ]----------------- */
XBT_INFO("Then, build a parallel task involving only computations and no communication (1 Gflop per node)");
- computation_amounts = new double[hosts_count]();
- for (int i = 0; i < hosts_count; i++)
- computation_amounts[i] = 1e9; // 1 Gflop
- simgrid::s4u::this_actor::parallel_execute(hosts_count, hosts, computation_amounts, nullptr /* no comm */);
+ computation_amounts.assign(hosts.size(), 1e9 /*1Gflop*/);
+ communication_amounts.clear(); /* no comm */
+ simgrid::s4u::this_actor::parallel_execute(hosts, computation_amounts, communication_amounts);
+
+ /* ------[ test 4 ]----------------- */
+ XBT_INFO("Then, build a parallel task involving only heterogeneous computations and no communication");
+ computation_amounts.resize(hosts.size());
+ for (int i = 0; i < hosts_count; i++)
+ computation_amounts[i] = 5 * (i + 1) * 1e8; // 500Mflop, 1Gflop, 1.5Gflop
+ communication_amounts.clear(); /* no comm */
+ simgrid::s4u::this_actor::parallel_execute(hosts, computation_amounts, communication_amounts);
+ /* ------[ test 5 ]----------------- */
XBT_INFO("Then, build a parallel task with no computation nor communication (synchro only)");
- computation_amounts = new double[hosts_count]();
- communication_amounts = new double[hosts_count * hosts_count]();
- simgrid::s4u::this_actor::parallel_execute(hosts_count, hosts, computation_amounts, communication_amounts);
+ computation_amounts.clear();
+ communication_amounts.clear();
+ simgrid::s4u::this_actor::parallel_execute(hosts, computation_amounts, communication_amounts);
- XBT_INFO("Finally, trick the ptask to do a 'remote execution', on host %s", hosts[1]->getCname());
- computation_amounts = new double[1]{1e9};
+ /* ------[ test 6 ]----------------- */
+ XBT_INFO("Finally, trick the ptask to do a 'remote execution', on host %s", hosts[1]->get_cname());
+ std::vector<simgrid::s4u::Host*> remote;
+ remote.push_back(hosts[1]);
+ computation_amounts.assign(1, 1e9);
+ communication_amounts.clear();
- simgrid::s4u::Host* remote[] = {hosts[1]};
- simgrid::s4u::this_actor::parallel_execute(1, remote, computation_amounts, nullptr);
+ simgrid::s4u::this_actor::parallel_execute(remote, computation_amounts, communication_amounts);
XBT_INFO("Goodbye now!");
- std::free(hosts);
}
int main(int argc, char* argv[])
if (argc == 3 && argv[2][2] == 'e')
sg_host_energy_plugin_init();
- e.loadPlatform(argv[1]);
+ e.load_platform(argv[1]);
/* Pick a process, no matter which, from the platform file */
- simgrid::s4u::Actor::createActor("test", simgrid::s4u::Host::by_name("MyHost1"), runner);
+ simgrid::s4u::Actor::create("test", simgrid::s4u::Host::by_name("MyHost1"), runner);
e.run();
XBT_INFO("Simulation done.");
