1 /* Copyright (c) 2010-2018. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 /* This example shows how to use simgrid::s4u::this_actor::wait_any() to wait for the first occurring event.
8 * As for the other asynchronous examples, the sender initiate all the messages it wants to send and
9 * pack the resulting simgrid::s4u::CommPtr objects in a vector. All messages thus occurs concurrently.
11 * The sender then loops until there is no ongoing communication. Using wait_any() ensures that the sender
12 * will notice events as soon as they occur even if it does not follow the order of the container.
14 * Here, finalize messages will terminate earlier because their size is 0, so they travel faster than the
15 * other messages of this application. As expected, the trace shows that the finalize of worker 1 is
16 * processed before 'Message 5' that is sent to worker 0.
20 #include "simgrid/s4u.hpp"
25 XBT_LOG_NEW_DEFAULT_CATEGORY(msg_async_waitall, "Messages specific for this msg example");
28 long messages_count; /* - number of tasks */
29 long receivers_count; /* - number of receivers */
30 double msg_size; /* - communication cost in bytes */
33 explicit Sender(std::vector<std::string> args)
35 xbt_assert(args.size() == 4, "Expecting 3 parameters from the XML deployment file but got %zu", args.size());
36 messages_count = std::stol(args[1]);
37 msg_size = std::stod(args[2]);
38 receivers_count = std::stol(args[3]);
42 std::vector<simgrid::s4u::CommPtr> pending_comms;
44 /* Start dispatching all messages to receivers, in a round robin fashion */
45 for (int i = 0; i < messages_count; i++) {
47 std::string mboxName = std::string("receiver-") + std::to_string(i % receivers_count);
48 simgrid::s4u::MailboxPtr mbox = simgrid::s4u::Mailbox::byName(mboxName);
49 std::string msgName = std::string("Message ") + std::to_string(i);
50 std::string* payload = new std::string(msgName); // copy the data we send:
51 // 'msgName' is not a stable storage location
52 XBT_INFO("Send '%s' to '%s'", msgName.c_str(), mboxName.c_str());
53 /* Create a communication representing the ongoing communication */
54 simgrid::s4u::CommPtr comm = mbox->put_async(payload, msg_size);
55 /* Add this comm to the vector of all known comms */
56 pending_comms.push_back(comm);
59 /* Start sending messages to let the workers know that they should stop */
60 for (int i = 0; i < receivers_count; i++) {
61 std::string mboxName = std::string("receiver-") + std::to_string(i % receivers_count);
62 simgrid::s4u::MailboxPtr mbox = simgrid::s4u::Mailbox::byName(mboxName);
63 std::string* payload = new std::string("finalize"); // Make a copy of the data we will send
65 simgrid::s4u::CommPtr comm = mbox->put_async(payload, 0);
66 pending_comms.push_back(comm);
67 XBT_INFO("Send 'finalize' to 'receiver-%ld'", i % receivers_count);
69 XBT_INFO("Done dispatching all messages");
71 /* Now that all message exchanges were initiated, wait for their completion, in order of termination.
73 * This loop waits for first terminating message with wait_any() and remove it with erase(), until all comms are
75 * Even in this simple example, the pending comms do not terminate in the exact same order of creation.
77 while (not pending_comms.empty()) {
78 int changed_pos = simgrid::s4u::Comm::wait_any(&pending_comms);
79 pending_comms.erase(pending_comms.begin() + changed_pos);
81 XBT_INFO("Remove the %dth pending comm: it terminated earlier than another comm that was initiated first.",
85 XBT_INFO("Goodbye now!");
89 /* Receiver actor expects 1 argument: its ID */
91 simgrid::s4u::MailboxPtr mbox;
94 explicit Receiver(std::vector<std::string> args)
96 xbt_assert(args.size() == 2, "Expecting one parameter from the XML deployment file but got %zu", args.size());
97 std::string mboxName = std::string("receiver-") + args[1];
98 mbox = simgrid::s4u::Mailbox::byName(mboxName);
102 XBT_INFO("Wait for my first message");
103 for (bool cont = true; cont;) {
104 std::string* received = static_cast<std::string*>(mbox->get());
105 XBT_INFO("I got a '%s'.", received->c_str());
106 cont = (*received != "finalize"); // If it's a finalize message, we're done
107 // Receiving the message was all we were supposed to do
113 int main(int argc, char *argv[])
115 xbt_assert(argc > 2, "Usage: %s platform_file deployment_file\n", argv[0]);
117 simgrid::s4u::Engine e(&argc, argv);
118 e.register_function<Sender>("sender");
119 e.register_function<Receiver>("receiver");
121 e.load_platform(argv[1]);
122 e.load_deployment(argv[2]);