1 /* Copyright (c) 2010-2022. 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 block on the completion of a set of communications.
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 occur concurrently.
11 * The sender then blocks until all ongoing communication terminate, using simgrid::s4u::Comm::wait_all()
15 #include "simgrid/s4u.hpp"
19 namespace sg4 = simgrid::s4u;
21 XBT_LOG_NEW_DEFAULT_CATEGORY(s4u_async_waitall, "Messages specific for this s4u example");
23 static void sender(unsigned int messages_count, unsigned int receivers_count, long msg_size)
25 // sphinx-doc: init-begin (this line helps the doc to build; ignore it)
26 /* Vector in which we store all ongoing communications */
27 std::vector<sg4::CommPtr> pending_comms;
29 /* Make a vector of the mailboxes to use */
30 std::vector<sg4::Mailbox*> mboxes;
31 for (unsigned int i = 0; i < receivers_count; i++)
32 mboxes.push_back(sg4::Mailbox::by_name(std::string("receiver-") + std::to_string(i)));
33 // sphinx-doc: init-end
35 /* Start dispatching all messages to receivers, in a round robin fashion */
36 for (unsigned int i = 0; i < messages_count; i++) {
37 std::string msg_content = std::string("Message ") + std::to_string(i);
38 // Copy the data we send: the 'msg_content' variable is not a stable storage location.
39 // It will be destroyed when this actor leaves the loop, ie before the receiver gets it
40 auto* payload = new std::string(msg_content);
42 XBT_INFO("Send '%s' to '%s'", msg_content.c_str(), mboxes[i % receivers_count]->get_cname());
44 /* Create a communication representing the ongoing communication, and store it in pending_comms */
45 sg4::CommPtr comm = mboxes[i % receivers_count]->put_async(payload, msg_size);
46 pending_comms.push_back(comm);
49 /* Start sending messages to let the workers know that they should stop */ // sphinx-doc: put-begin
50 for (unsigned int i = 0; i < receivers_count; i++) {
51 XBT_INFO("Send 'finalize' to 'receiver-%u'", i);
52 sg4::CommPtr comm = mboxes[i]->put_async(new std::string("finalize"), 0);
53 pending_comms.push_back(comm);
55 XBT_INFO("Done dispatching all messages");
57 /* Now that all message exchanges were initiated, wait for their completion in one single call */
58 sg4::Comm::wait_all(pending_comms);
59 // sphinx-doc: put-end
61 XBT_INFO("Goodbye now!");
64 /* Receiver actor expects 1 argument: its ID */
65 static void receiver(int id)
67 sg4::Mailbox* mbox = sg4::Mailbox::by_name(std::string("receiver-") + std::to_string(id));
68 XBT_INFO("Wait for my first message");
69 for (bool cont = true; cont;) {
70 auto received = mbox->get_unique<std::string>();
71 XBT_INFO("I got a '%s'.", received->c_str());
72 cont = (*received != "finalize"); // If it's a finalize message, we're done
73 // Receiving the message was all we were supposed to do
77 int main(int argc, char* argv[])
79 sg4::Engine e(&argc, argv);
81 e.load_platform(argv[1]);
83 sg4::Actor::create("sender", e.host_by_name("Tremblay"), sender, 5, 2, 1e6);
84 sg4::Actor::create("receiver", e.host_by_name("Ruby"), receiver, 0);
85 sg4::Actor::create("receiver", e.host_by_name("Perl"), receiver, 1);