=====================
SimGrid was conceived as a tool to study distributed algorithms. Its
-modern :ref:`S4U interface <S4U_doc>` makes it easy to assess Cloud,
-P2P, HPC, IoT, and similar settings.
+:ref:`S4U interface <S4U_doc>` makes it easy to assess Cloud,
+P2P, HPC, IoT, and other similar settings (:ref:`more info <index>`).
A typical SimGrid simulation is composed of several |Actors|_, that
execute user-provided functions. The actors have to explicitly use the
Each actor executes a user-provided function on a simulated |Host|_
with which it can interact. Communications are not directly sent to
-actors, but posted onto a |Mailbox|_ that serves as a rendezvous point
+actors, but posted onto a |Mailbox|_ that serves as a rendez-vous point
between communicating actors.
.. |Actors| replace:: **Actors**
application. We will detail each part of the code and the necessary
configuration to make it work. After this tour, several exercises
are proposed to let you discover some of the SimGrid features, hands
-on the keyboard. This practical session will be given in C++, which you
-are supposed to know beforehand.
+on the keyboard. This practical session will be given in C++ or Python,
+which you are supposed to know beforehand.
Discover the Master/Workers
.. SimGrid documentation master file
+.. _index:
+
The Modern Age of Computer Systems Simulation
=============================================
* under the terms of the license (GNU LGPL) which comes with this package. */
/* ************************************************************************* */
-/* Take this tutorial online: https://simgrid.frama.io/simgrid/tuto_s4u.html */
+/* Take this tutorial online: https://simgrid.org/doc/latest/Tutorial_Algorithms.html */
/* ************************************************************************* */
#include <simgrid/s4u.hpp>
* under the terms of the license (GNU LGPL) which comes with this package. */
/* ************************************************************************* */
-/* Take this tutorial online: https://simgrid.frama.io/simgrid/tuto_s4u.html */
+/* Take this tutorial online: https://simgrid.org/doc/latest/Tutorial_Algorithms.html */
/* ************************************************************************* */
#include <simgrid/s4u.hpp>
foreach(example actor-create actor-daemon actor-join actor-kill actor-migrate actor-suspend actor-yield actor-lifetime
+ app-masterworkers
comm-wait comm-waitall comm-waitany
exec-async exec-basic exec-dvfs exec-remote
network-nonlinear clusters-multicpu io-degradation exec-cpu-nonlinear)
--- /dev/null
+# Copyright (c) 2010-2022. 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.
+
+# ##################################################################################
+# Take this tutorial online: https://simgrid.org/doc/latest/Tutorial_Algorithms.html
+# ##################################################################################
+
+from simgrid import Actor, Engine, Host, Mailbox, this_actor
+import sys
+
+def master(*args):
+ if len(args) < 2:
+ raise AssertionError(
+ f"Actor master requires 3 parameters plus the workers' names, but got only {len(args)}")
+ tasks_count = int(args[0])
+ compute_cost = int(args[1])
+ communicate_cost = int(args[2])
+ workers = []
+ for i in range(3, len(args)):
+ workers.append(Mailbox.by_name(args[i]))
+ this_actor.info(f"Got {len(workers)} workers and {tasks_count} tasks to process")
+
+ for i in range(tasks_count): # For each task to be executed:
+ # - Select a worker in a round-robin way
+ mailbox = workers[i % len(workers)]
+
+ # - Send the computation amount to the worker
+ if (tasks_count < 10000 or (tasks_count < 100000 and i % 10000 == 0) or i % 100000 == 0):
+ this_actor.info(f"Sending task {i} of {tasks_count} to mailbox '{mailbox.name}'")
+ mailbox.put(compute_cost, communicate_cost)
+
+ this_actor.info("All tasks have been dispatched. Request all workers to stop.")
+ for i in range (len(workers)):
+ # The workers stop when receiving a negative compute_cost
+ mailbox = workers[i]
+ mailbox.put(-1, 0)
+
+def worker(*args):
+ assert len(args) == 0, "The worker expects to not get any argument"
+
+ mailbox = Mailbox.by_name(this_actor.get_host().name)
+ done = False
+ while not done:
+ compute_cost = mailbox.get()
+ if compute_cost > 0: # If compute_cost is valid, execute a computation of that cost
+ this_actor.execute(compute_cost)
+ else: # Stop when receiving an invalid compute_cost
+ done = True
+
+ this_actor.info("Exiting now.")
+
+if __name__ == '__main__':
+ assert len(sys.argv) > 2, f"Usage: python app-masterworkers.py platform_file deployment_file"
+
+ e = Engine(sys.argv)
+
+ # Register the classes representing the actors
+ e.register_actor("master", master)
+ e.register_actor("worker", worker)
+
+ # Load the platform description and then deploy the application
+ e.load_platform(sys.argv[1])
+ e.load_deployment(sys.argv[2])
+
+ # Run the simulation
+ e.run()
+
+ this_actor.info("Simulation is over")
--- /dev/null
+#!/usr/bin/env tesh
+
+p Testing a simple master/workers example application
+
+! output sort 19
+$ ${pythoncmd:=python3} ${PYTHON_TOOL_OPTIONS:=} ${bindir:=.}/app-masterworkers.py ${platfdir}/small_platform.xml app-masterworkers_d.xml --trace "--log=root.fmt:[%10.6r]%e(%a@%h)%e%m%n"
+> [ 0.000000] (master@Tremblay) Got 5 workers and 20 tasks to process
+> [ 0.000000] (master@Tremblay) Sending task 0 of 20 to mailbox 'Tremblay'
+> [ 0.002265] (master@Tremblay) Sending task 1 of 20 to mailbox 'Jupiter'
+> [ 0.171420] (master@Tremblay) Sending task 2 of 20 to mailbox 'Fafard'
+> [ 0.329817] (master@Tremblay) Sending task 3 of 20 to mailbox 'Ginette'
+> [ 0.453549] (master@Tremblay) Sending task 4 of 20 to mailbox 'Bourassa'
+> [ 0.586168] (master@Tremblay) Sending task 5 of 20 to mailbox 'Tremblay'
+> [ 0.588433] (master@Tremblay) Sending task 6 of 20 to mailbox 'Jupiter'
+> [ 0.995917] (master@Tremblay) Sending task 7 of 20 to mailbox 'Fafard'
+> [ 1.154314] (master@Tremblay) Sending task 8 of 20 to mailbox 'Ginette'
+> [ 1.608379] (master@Tremblay) Sending task 9 of 20 to mailbox 'Bourassa'
+> [ 1.749885] (master@Tremblay) Sending task 10 of 20 to mailbox 'Tremblay'
+> [ 1.752150] (master@Tremblay) Sending task 11 of 20 to mailbox 'Jupiter'
+> [ 1.921304] (master@Tremblay) Sending task 12 of 20 to mailbox 'Fafard'
+> [ 2.079701] (master@Tremblay) Sending task 13 of 20 to mailbox 'Ginette'
+> [ 2.763209] (master@Tremblay) Sending task 14 of 20 to mailbox 'Bourassa'
+> [ 2.913601] (master@Tremblay) Sending task 15 of 20 to mailbox 'Tremblay'
+> [ 2.915867] (master@Tremblay) Sending task 16 of 20 to mailbox 'Jupiter'
+> [ 3.085021] (master@Tremblay) Sending task 17 of 20 to mailbox 'Fafard'
+> [ 3.243418] (master@Tremblay) Sending task 18 of 20 to mailbox 'Ginette'
+> [ 3.918038] (master@Tremblay) Sending task 19 of 20 to mailbox 'Bourassa'
+> [ 4.077318] (master@Tremblay) All tasks have been dispatched. Request all workers to stop.
+> [ 4.077513] (worker@Tremblay) Exiting now.
+> [ 4.096528] (worker@Jupiter) Exiting now.
+> [ 4.122236] (worker@Fafard) Exiting now.
+> [ 4.965689] (worker@Ginette) Exiting now.
+> [ 5.133855] (maestro@) Simulation is over
+> [ 5.133855] (worker@Bourassa) Exiting now.
--- /dev/null
+<?xml version='1.0'?>
+<!DOCTYPE platform SYSTEM "https://simgrid.org/simgrid.dtd">
+<platform version="4.1">
+ <!-- The master actor (with some arguments) -->
+ <actor host="Tremblay" function="master">
+ <argument value="20"/> <!-- Number of tasks -->
+ <argument value="50000000"/> <!-- Computation size of tasks -->
+ <argument value="1000000"/> <!-- Communication size of tasks -->
+ <!-- name of hosts on which the workers are running -->
+ <argument value="Tremblay"/>
+ <argument value="Jupiter" />
+ <argument value="Fafard" />
+ <argument value="Ginette" />
+ <argument value="Bourassa" />
+ </actor>
+ <!-- The worker actors (with no argument) -->
+ <actor host="Tremblay" function="worker" />
+ <actor host="Jupiter" function="worker" />
+ <actor host="Fafard" function="worker" />
+ <actor host="Ginette" function="worker" />
+ <actor host="Bourassa" function="worker" />
+</platform>
