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 if (messages_count == 0 || receivers_count == 0) {
26 XBT_WARN("Sender has nothing to do. Bail out!");
29 // sphinx-doc: init-begin (this line helps the doc to build; ignore it)
30 /* Vector in which we store all ongoing communications */
31 std::vector<sg4::CommPtr> pending_comms;
33 /* Make a vector of the mailboxes to use */
34 std::vector<sg4::Mailbox*> mboxes;
35 for (unsigned int i = 0; i < receivers_count; i++)
36 mboxes.push_back(sg4::Mailbox::by_name("receiver-" + std::to_string(i)));
37 // sphinx-doc: init-end
39 /* Start dispatching all messages to receivers, in a round robin fashion */
40 for (unsigned int i = 0; i < messages_count; i++) {
41 std::string msg_content = "Message " + std::to_string(i);
42 // Copy the data we send: the 'msg_content' variable is not a stable storage location.
43 // It will be destroyed when this actor leaves the loop, ie before the receiver gets it
44 auto* payload = new std::string(msg_content);
46 XBT_INFO("Send '%s' to '%s'", msg_content.c_str(), mboxes[i % receivers_count]->get_cname());
48 /* Create a communication representing the ongoing communication, and store it in pending_comms */
49 sg4::CommPtr comm = mboxes[i % receivers_count]->put_async(payload, msg_size);
50 pending_comms.push_back(comm);
53 /* Start sending messages to let the workers know that they should stop */ // sphinx-doc: put-begin
54 for (unsigned int i = 0; i < receivers_count; i++) {
55 XBT_INFO("Send 'finalize' to 'receiver-%u'", i);
56 sg4::CommPtr comm = mboxes[i]->put_async(new std::string("finalize"), 0);
57 pending_comms.push_back(comm);
59 XBT_INFO("Done dispatching all messages");
61 /* Now that all message exchanges were initiated, wait for their completion in one single call */
62 sg4::Comm::wait_all(pending_comms);
63 // sphinx-doc: put-end
65 XBT_INFO("Goodbye now!");
68 /* Receiver actor expects 1 argument: its ID */
69 static void receiver(int id)
71 sg4::Mailbox* mbox = sg4::Mailbox::by_name("receiver-" + std::to_string(id));
72 XBT_INFO("Wait for my first message");
73 for (bool cont = true; cont;) {
74 auto received = mbox->get_unique<std::string>();
75 XBT_INFO("I got a '%s'.", received->c_str());
76 cont = (*received != "finalize"); // If it's a finalize message, we're done
77 // Receiving the message was all we were supposed to do
81 int main(int argc, char* argv[])
83 sg4::Engine e(&argc, argv);
85 e.load_platform(argv[1]);
87 sg4::Actor::create("sender", e.host_by_name("Tremblay"), sender, 5, 2, 1e6);
88 sg4::Actor::create("receiver", e.host_by_name("Ruby"), receiver, 0);
89 sg4::Actor::create("receiver", e.host_by_name("Perl"), receiver, 1);