+/* Copyright (c) 2017-2023. 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. */
+
+/* This example illustrates how to use Simgrid Tasks to reproduce the workflow 2.a of the article
+ * "Automated performance prediction of microservice applications using simulation" by Clément Courageux-Sudan et al.
+ *
+ * To build this workflow we create;
+ * - each Execution Task
+ * - each Communication Task
+ * - the links between the Tasks, i.e. the graph
+ *
+ * We also increase the parallelism degree of each Task to 10.
+ *
+ * In this scenario we send 500 requests per second (RPS) to the entry point of the graph for 7 seconds,
+ * and we count the number of processed requests between 2 and 7 seconds to evaluate the number of requests processed
+ * per second.
+ */
+
+#include "simgrid/s4u.hpp"
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(task_microservice, "Messages specific for this s4u example");
+namespace sg4 = simgrid::s4u;
+
+static void request_sender(sg4::TaskPtr t, int requests_per_second)
+{
+ for (int i = 0; i < requests_per_second * 7; i++) {
+ t->enqueue_firings(1);
+ sg4::this_actor::sleep_for(1.0 / requests_per_second);
+ }
+}
+
+int main(int argc, char* argv[])
+{
+ sg4::Engine e(&argc, argv);
+ e.load_platform(argv[1]);
+
+ // Retrieve Hosts
+ auto pm0 = e.host_by_name("PM0");
+ auto pm1 = e.host_by_name("PM1");
+
+ // Set concurrency limit
+ pm0->set_concurrency_limit(10);
+ pm1->set_concurrency_limit(10);
+
+ // Create Exec Tasks
+ auto nginx_web_server = sg4::ExecTask::init("nginx_web_server", 783 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_0 = sg4::ExecTask::init("compose_post_service_0", 682 * pm0->get_speed() / 1e6, pm0);
+ auto unique_id_service = sg4::ExecTask::init("unique_id_service", 12 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_1 = sg4::ExecTask::init("compose_post_service_1", 140 * pm0->get_speed() / 1e6, pm0);
+ auto media_service = sg4::ExecTask::init("media_service", 6 * pm1->get_speed() / 1e6, pm1);
+ auto compose_post_service_2 = sg4::ExecTask::init("compose_post_service_2", 135 * pm0->get_speed() / 1e6, pm0);
+ auto user_service = sg4::ExecTask::init("user_service", 5 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_3 = sg4::ExecTask::init("compose_post_service_3", 147 * pm0->get_speed() / 1e6, pm0);
+ auto text_service_0 = sg4::ExecTask::init("text_service_0", 296 * pm0->get_speed() / 1e6, pm0);
+ auto text_service_1 = sg4::ExecTask::init("text_service_1", 350 * pm0->get_speed() / 1e6, pm0);
+ auto text_service_2 = sg4::ExecTask::init("text_service_2", 146 * pm0->get_speed() / 1e6, pm0);
+ auto user_mention_service = sg4::ExecTask::init("user_mention_service", 934 * pm0->get_speed() / 1e6, pm0);
+ auto url_shorten_service = sg4::ExecTask::init("url_shorten_service", 555 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_4 = sg4::ExecTask::init("compose_post_service_4", 138 * pm0->get_speed() / 1e6, pm0);
+ auto home_timeline_service_0 = sg4::ExecTask::init("home_timeline_service_0", 243 * pm0->get_speed() / 1e6, pm0);
+ auto social_graph_service = sg4::ExecTask::init("home_timeline_service_0", 707 * pm0->get_speed() / 1e6, pm0);
+ auto home_timeline_service_1 = sg4::ExecTask::init("home_timeline_service_0", 7 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_5 = sg4::ExecTask::init("compose_post_service_5", 192 * pm0->get_speed() / 1e6, pm0);
+ auto user_timeline_service = sg4::ExecTask::init("user_timeline_service", 913 * pm0->get_speed() / 1e6, pm0);
+ auto compose_post_service_6 = sg4::ExecTask::init("compose_post_service_6", 508 * pm0->get_speed() / 1e6, pm0);
+ auto post_storage_service = sg4::ExecTask::init("post_storage_service", 391 * pm1->get_speed() / 1e6, pm1);
+
+ // Create Comm Tasks
+ auto compose_post_service_1_to_media_service =
+ sg4::CommTask::init("compose_post_service_1_to_media_service", 100, pm0, pm1);
+ auto media_service_to_compose_post_service_2 =
+ sg4::CommTask::init("media_service_to_compose_post_service_2", 100, pm1, pm0);
+ auto compose_post_service_6_to_post_storage_service =
+ sg4::CommTask::init("media_service_to_compose_post_service_2", 100, pm1, pm0);
+
+ // Create the graph
+ nginx_web_server->add_successor(compose_post_service_0);
+ compose_post_service_0->add_successor(unique_id_service);
+ unique_id_service->add_successor(compose_post_service_1);
+ compose_post_service_1->add_successor(compose_post_service_1_to_media_service);
+ compose_post_service_1_to_media_service->add_successor(media_service);
+ media_service->add_successor(media_service_to_compose_post_service_2);
+ media_service_to_compose_post_service_2->add_successor(compose_post_service_2);
+ compose_post_service_2->add_successor(user_service);
+ user_service->add_successor(compose_post_service_3);
+ compose_post_service_3->add_successor(text_service_0);
+ text_service_0->add_successor(text_service_1);
+ text_service_0->add_successor(text_service_2);
+ text_service_1->add_successor(user_mention_service);
+ text_service_2->add_successor(url_shorten_service);
+ user_mention_service->add_successor(compose_post_service_4);
+ compose_post_service_4->add_successor(home_timeline_service_0);
+ home_timeline_service_0->add_successor(social_graph_service);
+ social_graph_service->add_successor(home_timeline_service_1);
+ home_timeline_service_1->add_successor(compose_post_service_5);
+ compose_post_service_5->add_successor(user_timeline_service);
+ user_timeline_service->add_successor(compose_post_service_6);
+ compose_post_service_6->add_successor(compose_post_service_6_to_post_storage_service);
+ compose_post_service_6_to_post_storage_service->add_successor(post_storage_service);
+
+ // Dispatch Exec Tasks
+ std::vector<sg4::TaskPtr> exec_tasks = {nginx_web_server,
+ compose_post_service_0,
+ unique_id_service,
+ compose_post_service_1,
+ compose_post_service_1_to_media_service,
+ media_service,
+ media_service_to_compose_post_service_2,
+ compose_post_service_2,
+ user_service,
+ compose_post_service_3,
+ text_service_0,
+ text_service_1,
+ text_service_2,
+ user_mention_service,
+ url_shorten_service,
+ compose_post_service_4,
+ home_timeline_service_0,
+ social_graph_service,
+ home_timeline_service_1,
+ compose_post_service_5,
+ user_timeline_service,
+ compose_post_service_6,
+ compose_post_service_6_to_post_storage_service,
+ post_storage_service};
+ for (auto t : exec_tasks)
+ t->set_parallelism_degree(10);
+
+ // Create the actor that will inject requests during the simulation
+ sg4::Actor::create("request_sender", pm0, request_sender, nginx_web_server, 500);
+
+ // Add a function to be called when tasks end for log purpose
+ int requests_processed = 0;
+ sg4::Task::on_completion_cb([&e, &requests_processed](const sg4::Task* t) {
+ if (t->get_name() == "post_storage_service" and e.get_clock() < 7 and e.get_clock() > 2)
+ requests_processed++;
+ });
+
+ // Start the simulation
+ e.run();
+ XBT_INFO("Requests processed per second: %f", requests_processed / 5.0);
+ return 0;
+}