1 .. S4U (Simgrid for you) is the modern interface of SimGrid, which new project should use.
3 .. This file follows the ReStructured syntax to be included in the
4 .. documentation, but it should remain readable directly.
11 SimGrid comes with an extensive set of examples, documented on this
12 page. Most of them only demonstrate one single feature, with some
13 larger exemplars listed below.
15 The C++ examples can be found under examples/cpp while python examples
16 are in examples/python. Each such directory contains the source code (also listed
17 from this page), and the so-called tesh file containing how to call
18 the binary obtained by compiling this example and also the expected
19 output. Tesh files are used to turn each of our examples into an
20 integration test. Some examples also contain other files, on need.
22 A good way to bootstrap your own project is to copy and combine some
23 of the provided examples to constitute the skeleton of what you plan
28 ===========================
29 Actors: the Active Entities
30 ===========================
32 Starting and Stopping Actors
33 ----------------------------
35 - **Creating actors:**
36 Most actors are started from the deployment XML file because this
37 is a :ref:`better scientific habit <howto_science>`, but you can
38 also create them directly from your code.
42 .. example-tab:: examples/cpp/actor-create/s4u-actor-create.cpp
44 You create actors either:
46 - Directly with :cpp:func:`simgrid::s4u::Actor::create`
47 - From XML with :cpp:func:`simgrid::s4u::Engine::register_actor` (if your actor is a class)
48 or :cpp:func:`simgrid::s4u::Engine::register_function` (if your actor is a function)
49 and then :cpp:func:`simgrid::s4u::Engine::load_deployment`
51 .. example-tab:: examples/python/actor-create/actor-create.py
53 You create actors either:
55 - Directly with :py:func:`simgrid.Actor.create()`
56 - From XML with :py:func:`simgrid.Engine.register_actor()` and then :py:func:`simgrid.Engine.load_deployment()`
58 .. example-tab:: examples/c/actor-create/actor-create.c
60 You create actors either:
62 - Directly with :cpp:func:`sg_actor_create` followed by :cpp:func:`sg_actor_start`.
63 - From XML with :cpp:func:`simgrid_register_function` and then :cpp:func:`simgrid_load_deployment`.
65 .. example-tab:: examples/python/actor-create/actor-create_d.xml
67 The following file is used in both C++ and Python.
69 - **React to the end of actors:** You can attach callbacks to the end of
70 actors. There are several ways of doing so, depending on whether you want to
71 attach your callback to a given actor and on how you define the end of a
72 given actor. User code probably wants to react to the termination of an actor
73 while some plugins want to react to the destruction (memory collection) of
78 .. example-tab:: examples/cpp/actor-exiting/s4u-actor-exiting.cpp
80 This example shows how to attach a callback to:
82 - the end of a specific actor: :cpp:func:`simgrid::s4u::Actor::on_exit()`
83 - the end of any actor: :cpp:member:`simgrid::s4u::Actor::on_termination()`
84 - the destruction of any actor: :cpp:member:`simgrid::s4u::Actor::on_destruction()`
86 .. example-tab:: examples/c/actor-exiting/actor-exiting.c
88 This example shows how to attach a callback to the end of a specific actor with
89 :cpp:func:`sg_actor_on_exit()`.
92 Actors can forcefully stop other actors.
96 .. example-tab:: examples/cpp/actor-kill/s4u-actor-kill.cpp
98 See also :cpp:func:`void simgrid::s4u::Actor::kill(void)`, :cpp:func:`void simgrid::s4u::Actor::kill_all()`,
99 :cpp:func:`simgrid::s4u::this_actor::exit`, :cpp:func:`simgrid::s4u::Actor::on_exit`.
101 .. example-tab:: examples/python/actor-kill/actor-kill.py
103 See also :py:func:`simgrid.Actor.kill`, :py:func:`simgrid.Actor.kill_all`, :py:func:`simgrid.this_actor.exit`,
104 :py:func:`simgrid.this_actor.on_exit`.
106 .. example-tab:: examples/c/actor-kill/actor-kill.c
108 See also :cpp:func:`sg_actor_kill`, :cpp:func:`sg_actor_kill_all`, :cpp:func:`sg_actor_exit`, :cpp:func:`sg_actor_on_exit`.
110 - **Controlling the actor life cycle from the XML:**
111 You can specify a start time and a kill time in the deployment file.
115 .. example-tab:: examples/cpp/actor-lifetime/s4u-actor-lifetime.cpp
117 This file is not really interesting: the important matter is in the XML file.
119 .. example-tab:: examples/cpp/actor-lifetime/s4u-actor-lifetime_d.xml
121 This demonstrates the ``start_time`` and ``kill_time`` attribute of the :ref:`pf_tag_actor` tag.
123 .. example-tab:: examples/python/actor-lifetime/actor-lifetime.py
125 This file is not really interesting: the important matter is in the XML file.
127 .. example-tab:: examples/c/actor-lifetime/actor-lifetime.c
129 This file is not really interesting: the important matter is in the XML file.
131 - **Daemonize actors:**
132 Some actors may be intended to simulate daemons that run in the background.
133 This example shows how to transform a regular
134 actor into a daemon that will be automatically killed once the simulation is over.
138 .. example-tab:: examples/cpp/actor-daemon/s4u-actor-daemon.cpp
140 See also :cpp:func:`simgrid::s4u::Actor::daemonize()` and :cpp:func:`simgrid::s4u::Actor::is_daemon()`.
142 .. example-tab:: examples/python/actor-daemon/actor-daemon.py
144 See also :py:func:`simgrid.Actor.daemonize()` and :py:func:`simgrid.Actor.is_daemon()`.
146 .. example-tab:: examples/c/actor-daemon/actor-daemon.c
148 See also :cpp:func:`sg_actor_daemonize` and :cpp:func:`sg_actor_is_daemon`.
150 - **Specify the stack size to use**
151 The stack size can be specified by default on the command line,
152 globally by changing the configuration with :cpp:func:`simgrid::s4u::Engine::set_config`,
153 or for a specific actor using :cpp:func:`simgrid::s4u::Actor::set_stacksize` before its start.
157 .. example-tab:: examples/cpp/actor-stacksize/s4u-actor-stacksize.cpp
159 .. example-tab:: examples/c/actor-stacksize/actor-stacksize.c
161 Inter-Actors Interactions
162 -------------------------
164 See also the examples on :ref:`inter-actors communications
165 <s4u_ex_communication>` and the ones on :ref:`classical
166 synchronization objects <s4u_ex_IPC>`.
168 - **Suspend and Resume actors:**
169 Actors can be suspended and resumed during their executions.
173 .. example-tab:: examples/cpp/actor-suspend/s4u-actor-suspend.cpp
175 See also :cpp:func:`simgrid::s4u::this_actor::suspend()`,
176 :cpp:func:`simgrid::s4u::Actor::suspend()`, :cpp:func:`simgrid::s4u::Actor::resume()`, and
177 :cpp:func:`simgrid::s4u::Actor::is_suspended()`.
179 .. example-tab:: examples/python/actor-suspend/actor-suspend.py
181 See also :py:func:`simgrid.this_actor.suspend()`,
182 :py:func:`simgrid.Actor.suspend()`, :py:func:`simgrid.Actor.resume()`, and
183 :py:func:`simgrid.Actor.is_suspended()`.
185 .. example-tab:: examples/c/actor-suspend/actor-suspend.c
187 See also :cpp:func:`sg_actor_suspend()`, :cpp:func:`sg_actor_resume()`, and
188 :cpp:func:`sg_actor_is_suspended()`.
190 - **Migrating Actors:**
191 Actors can move or be moved from a host to another very easily. It amounts to setting them on a new host.
195 .. example-tab:: examples/cpp/actor-migrate/s4u-actor-migrate.cpp
197 See also :cpp:func:`simgrid::s4u::this_actor::set_host()` and :cpp:func:`simgrid::s4u::Actor::set_host()`.
199 .. example-tab:: examples/python/actor-migrate/actor-migrate.py
201 See also :py:func:`simgrid.this_actor.set_host()` and :py:func:`simgrid.Actor.set_host()`.
203 .. example-tab:: examples/c/actor-migrate/actor-migrate.c
205 See also :cpp:func:`sg_actor_set_host()`.
207 - **Waiting for the termination of an actor:** (joining on it)
208 You can block the current actor until the end of another actor.
212 .. example-tab:: examples/cpp/actor-join/s4u-actor-join.cpp
214 See also :cpp:func:`simgrid::s4u::Actor::join()`.
216 .. example-tab:: examples/python/actor-join/actor-join.py
218 See also :py:func:`simgrid.Actor.join()`.
220 .. example-tab:: examples/c/actor-join/actor-join.c
222 See also :cpp:func:`sg_actor_join`.
224 - **Yielding to other actors**.
225 The ```yield()``` function interrupts the execution of the current
226 actor, leaving a chance to the other actors that are ready to run
231 .. example-tab:: examples/cpp/actor-yield/s4u-actor-yield.cpp
233 See also :cpp:func:`simgrid::s4u::this_actor::yield()`.
235 .. example-tab:: examples/python/actor-yield/actor-yield.py
237 See also :py:func:`simgrid.this_actor.yield_()`.
239 .. example-tab:: examples/c/actor-yield/actor-yield.c
241 See also :cpp:func:`sg_actor_yield()`.
243 Traces Replay as a Workload
244 ---------------------------
246 This section details how to run trace-driven simulations. It is very
247 handy when you want to test an algorithm or protocol that only reacts
248 to external events. For example, many P2P protocols react to user
249 requests, but do nothing if there is no such event.
251 In such situations, you should write your protocol in C++, and separate
252 the workload that you want to play onto your protocol in a separate
253 text file. Declare a function handling each type of the events in your
254 trace, register them using :cpp:func:`xbt_replay_action_register()` in
255 your main, and then run the simulation.
257 Then, you can either have one trace file containing all your events,
258 or a file per simulated process: the former may be easier to work
259 with, but the second is more efficient on very large traces. Check
260 also the tesh files in the example directories for details.
262 - **Communication replay:**
263 Presents a set of event handlers reproducing classical communication
264 primitives (asynchronous send/receive at the moment).
268 .. example-tab:: examples/cpp/replay-comm/s4u-replay-comm.cpp
271 Presents a set of event handlers reproducing classical I/O
272 primitives (open, read, close).
276 .. example-tab:: examples/cpp/replay-io/s4u-replay-io.cpp
278 ==========================
279 Activities: what Actors do
280 ==========================
282 .. _s4u_ex_communication:
284 Communications on the Network
285 -----------------------------
287 - **Basic communications:**
288 This simple example just sends one message back and forth.
289 The tesh file laying in the directory shows how to start the simulator binary, highlighting how to pass options to
290 the simulators (as detailed in Section :ref:`options`).
294 .. example-tab:: examples/cpp/comm-pingpong/s4u-comm-pingpong.cpp
296 .. example-tab:: examples/c/comm-pingpong/comm-pingpong.c
299 - **Basic asynchronous communications:**
300 Illustrates how to have non-blocking communications, that are
301 communications running in the background leaving the process free
302 to do something else during their completion.
306 .. example-tab:: examples/cpp/comm-wait/s4u-comm-wait.cpp
308 See also :cpp:func:`simgrid::s4u::Mailbox::put_async()` and :cpp:func:`simgrid::s4u::Comm::wait()`.
310 .. example-tab:: examples/python/comm-wait/comm-wait.py
312 See also :py:func:`simgrid.Mailbox.put_async()` and :py:func:`simgrid.Comm.wait()`.
314 .. example-tab:: examples/c/comm-wait/comm-wait.c
316 See also :cpp:func:`sg_mailbox_put_async()` and :cpp:func:`sg_comm_wait()`.
318 - **Waiting for communications with timeouts:**
319 This example is very similar to the previous one, simply adding how to declare timeouts when waiting on asynchronous communication.
323 .. example-tab:: examples/cpp/comm-waituntil/s4u-comm-waituntil.cpp
325 See also :cpp:func:`simgrid::s4u::Activity::wait_until()` and :cpp:func:`simgrid::s4u::Comm::wait_for()`.
327 - **Suspending communications:**
328 The ``suspend()`` and ``resume()`` functions allow to block the
329 progression of a given communication for a while and then unblock it.
330 ``is_suspended()`` can be used to retrieve whether the activity is
331 currently blocked or not.
335 .. example-tab:: examples/cpp/comm-suspend/s4u-comm-suspend.cpp
337 See also :cpp:func:`simgrid::s4u::Activity::suspend()`
338 :cpp:func:`simgrid::s4u::Activity::resume()` and
339 :cpp:func:`simgrid::s4u::Activity::is_suspended()`.
342 - **Waiting for all communications in a set:**
343 The ``wait_all()`` function is useful when you want to block until
344 all activities in a given set have been completed.
348 .. example-tab:: examples/cpp/comm-waitall/s4u-comm-waitall.cpp
350 See also :cpp:func:`simgrid::s4u::Comm::wait_all()`.
352 .. example-tab:: examples/python/comm-waitall/comm-waitall.py
354 See also :py:func:`simgrid.Comm.wait_all()`.
356 .. example-tab:: examples/c/comm-waitall/comm-waitall.c
358 See also :cpp:func:`sg_comm_wait_all()`.
360 - **Waiting for the first completed communication in a set:**
361 The ``wait_any()`` function is useful
362 when you want to block until one activity of the set completes, no
363 matter which terminates first.
367 .. example-tab:: examples/cpp/comm-waitany/s4u-comm-waitany.cpp
369 See also :cpp:func:`simgrid::s4u::Comm::wait_any()`.
371 .. example-tab:: examples/python/comm-waitany/comm-waitany.py
373 See also :py:func:`simgrid.Comm.wait_any()`.
375 .. example-tab:: examples/c/comm-waitany/comm-waitany.c
377 See also :cpp:func:`sg_comm_wait_any`.
379 .. _s4u_ex_execution:
381 Executions on the CPU
382 ---------------------
384 - **Basic execution:**
385 The computations done in your program are not reported to the
386 simulated world unless you explicitly request the simulator to pause
387 the actor until a given amount of flops gets computed on its simulated
388 host. Some executions can be given a higher priority so that they
393 .. example-tab:: examples/cpp/exec-basic/s4u-exec-basic.cpp
395 See also :cpp:func:`void simgrid::s4u::this_actor::execute(double)`
396 and :cpp:func:`void simgrid::s4u::this_actor::execute(double, double)`.
398 .. example-tab:: examples/python/exec-basic/exec-basic.py
400 See also :py:func:`simgrid.this_actor.execute()`.
402 .. example-tab:: examples/c/exec-basic/exec-basic.c
404 See also :cpp:func:`void sg_actor_execute(double)`
405 and :cpp:func:`void sg_actor_execute_with_priority(double, double)`.
407 - **Asynchronous execution:**
408 You can start asynchronous executions, just like you would fire
413 .. example-tab:: examples/cpp/exec-async/s4u-exec-async.cpp
415 See also :cpp:func:`simgrid::s4u::this_actor::exec_init()`,
416 :cpp:func:`simgrid::s4u::Activity::start()`,
417 :cpp:func:`simgrid::s4u::Activity::wait()`,
418 :cpp:func:`simgrid::s4u::Activity::get_remaining()`,
419 :cpp:func:`simgrid::s4u::Exec::get_remaining_ratio()`,
420 :cpp:func:`simgrid::s4u::this_actor::exec_async()` and
421 :cpp:func:`simgrid::s4u::Activity::cancel()`.
423 .. example-tab:: examples/python/exec-async/exec-async.py
425 See also :py:func:`simgrid.this_actor::exec_init()`,
426 :py:func:`simgrid.Activity::start()`,
427 :py:func:`simgrid.Activity.wait()`,
428 :py:func:`simgrid.Activity.get_remaining()`,
429 :py:func:`simgrid.Exec.get_remaining_ratio()`,
430 :py:func:`simgrid.this_actor.exec_async()` and
431 :py:func:`simgrid.Activity.cancel()`.
433 .. example-tab:: examples/c/exec-async/exec-async.c
435 See also :cpp:func:`sg_actor_exec_init()`,
436 :cpp:func:`sg_exec_start()`,
437 :cpp:func:`sg_exec_wait()`,
438 :cpp:func:`sg_exec_get_remaining()`,
439 :cpp:func:`sg_exec_get_remaining_ratio()`,
440 :cpp:func:`sg_actor_exec_async()` and
441 :cpp:func:`sg_exec_cancel()`,
443 - **Remote execution:**
444 You can start executions on remote hosts, or even change the host
445 on which they occur during their execution.
449 .. example-tab:: examples/cpp/exec-remote/s4u-exec-remote.cpp
451 See also :cpp:func:`simgrid::s4u::Exec::set_host()`.
453 .. example-tab:: examples/python/exec-remote/exec-remote.py
455 See also :py:func:`simgrid.Exec.set_host()`.
457 .. example-tab:: examples/c/exec-remote/exec-remote.c
459 See also :cpp:func:`sg_exec_set_host()`.
461 - **Parallel executions:**
462 These objects are convenient abstractions of parallel
463 computational kernels that span over several machines, such as a
464 PDGEM and the other ScaLAPACK routines. Note that this only works
465 with the "ptask_L07" host model (``--cfg=host/model:ptask_L07``).
467 This example demonstrates several kinds of parallel tasks: regular
468 ones, communication-only (without computation), computation-only
469 (without communication), synchronization-only (neither
470 communication nor computation). It also shows how to reconfigure a
471 task after its start, to change the number of hosts it runs onto.
472 This allows simulating malleable tasks.
476 .. example-tab:: examples/cpp/exec-ptask/s4u-exec-ptask.cpp
478 See also :cpp:func:`simgrid::s4u::this_actor::parallel_execute()`.
480 - **Using Pstates on a host:**
481 This example shows how to define a set of pstates in the XML. The current pstate
482 of a host can then be accessed and changed from the program.
486 .. example-tab:: examples/cpp/exec-dvfs/s4u-exec-dvfs.cpp
488 See also :cpp:func:`simgrid::s4u::Host::get_pstate_speed` and :cpp:func:`simgrid::s4u::Host::set_pstate`.
490 .. example-tab:: examples/c/exec-dvfs/exec-dvfs.c
492 See also :cpp:func:`sg_host_get_pstate_speed` and :cpp:func:`sg_host_set_pstate`.
494 .. example-tab:: examples/python/exec-dvfs/exec-dvfs.py
496 See also :py:func:`Host.get_pstate_speed` and :py:func:`Host.set_pstate`.
498 .. example-tab:: examples/platforms/energy_platform.xml
502 I/O on Disks and Files
503 ----------------------
505 SimGrid provides two levels of abstraction to interact with the
506 simulated disks. At the simplest level, you simply create read and
507 write actions on the disk resources.
509 - **Access to raw disk devices:**
510 This example illustrates how to simply read and write data on a
511 simulated disk resource.
515 .. example-tab:: examples/cpp/io-disk-raw/s4u-io-disk-raw.cpp
517 .. example-tab:: examples/c/io-disk-raw/io-disk-raw.c
519 .. example-tab:: examples/platforms/hosts_with_disks.xml
521 This shows how to declare disks in XML.
523 The FileSystem plugin provides a more detailed view, with the
524 classical operations over files: open, move, unlink, and of course,
525 read and write. The file and disk sizes are also dealt with and can
526 result in short reads and short writes, as in reality.
528 - **File Management:**
529 This example illustrates the use of operations on files
530 (read, write, seek, tell, unlink, etc).
534 .. example-tab:: examples/cpp/io-file-system/s4u-io-file-system.cpp
537 I/O operations on files can also be done remotely,
538 i.e. when the accessed disk is not mounted on the caller's host.
542 .. example-tab:: examples/cpp/io-file-remote/s4u-io-file-remote.cpp
544 .. example-tab:: examples/c/io-file-remote/io-file-remote.c
548 Classical synchronization objects
549 ---------------------------------
552 Shows how to use :cpp:type:`simgrid::s4u::Barrier` synchronization objects.
556 .. example-tab:: examples/cpp/synchro-barrier/s4u-synchro-barrier.cpp
558 - **Condition variable: basic usage**
559 Shows how to use :cpp:type:`simgrid::s4u::ConditionVariable` synchronization objects.
563 .. example-tab:: examples/cpp/synchro-condition-variable/s4u-synchro-condition-variable.cpp
565 - **Condition variable: timeouts**
566 Shows how to specify timeouts when blocking on condition variables.
570 .. example-tab:: examples/cpp/synchro-condition-variable-waituntil/s4u-synchro-condition-variable-waituntil.cpp
573 Shows how to use :cpp:type:`simgrid::s4u::Mutex` synchronization objects.
577 .. example-tab:: examples/cpp/synchro-mutex/s4u-synchro-mutex.cpp
580 Shows how to use :cpp:type:`simgrid::s4u::Semaphore` synchronization objects.
584 .. example-tab:: examples/cpp/synchro-semaphore/s4u-synchro-semaphore.cpp
586 .. example-tab:: examples/c/synchro-semaphore/synchro-semaphore.c
588 =============================
589 Interacting with the Platform
590 =============================
592 - **User-defined properties:**
593 You can attach arbitrary information to most platform elements from
594 the XML file, and then interact with these values from your
595 program. Note that the changes are not written permanently on disk,
596 in the XML file nor anywhere else. They only last until the end of
601 .. example-tab:: examples/cpp/platform-properties/s4u-platform-properties.cpp
603 - :cpp:func:`simgrid::s4u::Actor::get_property()` and :cpp:func:`simgrid::s4u::Actor::set_property()`
604 - :cpp:func:`simgrid::s4u::Host::get_property()` and :cpp:func:`simgrid::s4u::Host::set_property()`
605 - :cpp:func:`simgrid::s4u::Link::get_property()` and :cpp:func:`simgrid::s4u::Link::set_property()`
606 - :cpp:func:`simgrid::s4u::NetZone::get_property()` and :cpp:func:`simgrid::s4u::NetZone::set_property()`
608 .. example-tab:: examples/c/platform-properties/platform-properties.c
610 - :cpp:func:`sg_actor_get_property_value()`
611 - :cpp:func:`sg_host_get_property_value()` and :cpp:func:sg_host_set_property_value()`
612 - :cpp:func:`sg_zone_get_property_value()` and :cpp:func:`sg_zone_set_property_value()`
618 .. showfile:: examples/cpp/platform-properties/s4u-platform-properties_d.xml
624 .. showfile:: examples/platforms/prop.xml
627 - **Retrieving the netzones matching given criteria:**
628 Shows how to filter the cluster netzones.
632 .. example-tab:: examples/cpp/routing-get-clusters/s4u-routing-get-clusters.cpp
634 - **Retrieving the list of hosts matching given criteria:**
635 Shows how to filter the actors that match given criteria.
639 .. example-tab:: examples/cpp/engine-filtering/s4u-engine-filtering.cpp
641 - **Specifying state profiles:** shows how to specify when the
642 resources must be turned off and on again, and how to react to such
643 failures in your code. See also :ref:`howto_churn`.
647 .. example-tab:: examples/cpp/platform-failures/s4u-platform-failures.cpp
649 .. example-tab:: examples/c/platform-failures/platform-failures.c
653 .. showfile:: examples/platforms/small_platform_failures.xml
656 .. showfile:: examples/platforms/profiles/jupiter_state.profile
658 .. showfile:: examples/platforms/profiles/bourassa_state.profile
660 .. showfile:: examples/platforms/profiles/fafard_state.profile
662 - **Specifying speed profiles:** shows how to specify an external
663 load to resources, variating their peak speed over time.
667 .. example-tab:: examples/cpp/platform-profile/s4u-platform-profile.cpp
671 .. showfile:: examples/platforms/small_platform_profile.xml
674 .. showfile:: examples/platforms/profiles/jupiter_speed.profile
676 .. showfile:: examples/platforms/profiles/link1_bandwidth.profile
678 .. showfile:: examples/platforms/profiles/link1_latency.profile
684 - **Describing the energy profiles in the platform:**
685 The first platform file contains the energy profile of each link and
686 host for a wired network, which is necessary to get energy consumption
687 predictions. The second platform file is the equivalent for a wireless
688 network. As usual, you should not trust our example, and you should
689 strive to double-check that your instantiation matches your target
696 .. showfile:: examples/platforms/energy_platform.xml
699 .. showfile:: examples/platforms/wifi_energy.xml
702 - **Consumption due to the CPU:**
703 This example shows how to retrieve the amount of energy consumed
704 by the CPU during computations, and the impact of the pstate.
708 .. example-tab:: examples/cpp/energy-exec/s4u-energy-exec.cpp
710 .. example-tab:: examples/c/energy-exec/energy-exec.c
712 - **Consumption due to the wired network:**
713 This example shows how to retrieve and display the energy consumed
714 by the wired network during communications.
718 .. example-tab:: examples/cpp/energy-link/s4u-energy-link.cpp
720 - **Consumption due to the wireless network:**
721 This example shows how to retrieve and display the energy consumed
722 by the wireless network during communications.
726 .. example-tab:: examples/cpp/energy-wifi/s4u-energy-wifi.cpp
728 - **Modeling the shutdown and boot of hosts:**
729 Simple example of a model for the energy consumption during
730 the host boot and shutdown periods.
734 .. example-tab:: examples/cpp/energy-boot/platform_boot.xml
736 .. example-tab:: examples/cpp/energy-boot/s4u-energy-boot.cpp
738 =======================
739 Tracing and Visualizing
740 =======================
742 Tracing can be activated by various configuration options which
743 are illustrated in these examples. See also the
744 :ref:`full list of options related to tracing <tracing_tracing_options>`.
746 It is interesting to run the process-create example with the following
747 options to see the task executions:
749 - **Platform Tracing:**
750 This program is a toy example just loading the platform so that
751 you can play with the platform visualization. Recommended options:
752 ``--cfg=tracing:yes --cfg=tracing/categorized:yes``
756 .. example-tab:: examples/cpp/trace-platform/s4u-trace-platform.cpp
758 - **Setting Categories**
759 This example declares several tracing categories that are used to
760 classify its tasks. When the program is executed, the tracing mechanism
761 registers the resource utilization of hosts and links according to these
762 categories. Recommended options:
763 ``--cfg=tracing:yes --cfg=tracing/categorized:yes --cfg=tracing/uncategorized:yes``
767 .. example-tab:: examples/cpp/trace-categories/s4u-trace-categories.cpp
769 - **Master Workers tracing**
770 This is an augmented version of our basic master/worker example using
771 several tracing features. It traces resource usage, sorted out in several
772 categories; Trace marks and user variables are also used. Recommended
773 options: ``--cfg=tracing/categorized:yes --cfg=tracing/uncategorized:yes``
777 .. example-tab:: examples/cpp/trace-masterworkers/s4u-trace-masterworkers.cpp
779 - **Process migration tracing**
780 This version is enhanced so that the process migrations can be displayed
781 as arrows in a Gantt-chart visualization. Recommended options to that
782 extend: ``--cfg=tracing:yes --cfg=tracing/actor:yes``
786 .. example-tab:: examples/cpp/trace-process-migration/s4u-trace-process-migration.cpp
789 TODO: These tracing examples should be integrated in the examples to not
790 duplicate the C++ files. A full command line to see the result in the right
791 tool (vite/FrameSoc) should be given along with some screenshots.
793 Tracing user variables
794 ----------------------
796 You can also attach your own variables to any resource described in the platform
797 file. The following examples illustrate this feature. They have to be run with
798 the following options: ``--cfg=tracing:yes --cfg=tracing/platform:yes``
800 - **Attaching variables to Hosts**
804 .. example-tab:: examples/cpp/trace-host-user-variables/s4u-trace-host-user-variables.cpp
806 - **Attaching variables to Links**
807 The tricky part is that you have to know the name of the link you want to
808 enhance with a variable.
812 .. example-tab:: examples/cpp/trace-link-user-variables/s4u-trace-link-user-variables.cpp
814 - **Attaching variables to network Routes**
815 It is often easier to update a given variable for all links of a given
816 network path (identified by its source and destination hosts) instead of
817 knowing the name of each specific link.
821 .. example-tab:: examples/cpp/trace-route-user-variables/s4u-trace-route-user-variables.cpp
823 ========================
824 Larger SimGrid Exemplars
825 ========================
827 This section contains application examples that are somewhat larger
828 than the previous examples.
831 Shows how to implement a classical communication pattern, where a
832 token is exchanged along a ring to reach every participant.
836 .. example-tab:: examples/cpp/app-token-ring/s4u-app-token-ring.cpp
838 .. example-tab:: examples/c/app-token-ring/app-token-ring.c
840 - **Master Workers:**
841 Another good old example, where one Master process has a bunch of tasks to dispatch to a set of several Worker
848 This example comes in two equivalent variants, one where the actors
849 are specified as simple functions (which is easier to understand for
850 newcomers) and one where the actors are specified as classes (which is
851 more powerful for the users wanting to build their own projects upon
854 .. showfile:: examples/cpp/app-masterworkers/s4u-app-masterworkers-class.cpp
857 .. showfile:: examples/cpp/app-masterworkers/s4u-app-masterworkers-fun.cpp
862 .. showfile:: examples/c/app-masterworker/app-masterworker.c
869 Classical protocol for Peer-to-Peer data diffusion.
875 .. showfile:: examples/cpp/app-bittorrent/s4u-bittorrent.cpp
878 .. showfile:: examples/cpp/app-bittorrent/s4u-peer.cpp
881 .. showfile:: examples/cpp/app-bittorrent/s4u-tracker.cpp
886 .. showfile:: examples/c/app-bittorrent/app-bittorrent.c
889 .. showfile:: examples/c/app-bittorrent/bittorrent-peer.c
892 .. showfile:: examples/c/app-bittorrent/tracker.c
896 Data broadcast over a ring of processes.
900 .. example-tab:: examples/cpp/app-chainsend/s4u-app-chainsend.cpp
904 .. showfile:: examples/c/app-chainsend/chainsend.c
907 .. showfile:: examples/c/app-chainsend/broadcaster.c
910 .. showfile:: examples/c/app-chainsend/peer.c
913 Distributed Hash Tables (DHT)
914 -----------------------------
917 One of the most famous DHT protocol.
923 .. showfile:: examples/cpp/dht-chord/s4u-dht-chord.cpp
926 .. showfile:: examples/cpp/dht-chord/s4u-dht-chord-node.cpp
930 Another well-known DHT protocol.
936 .. showfile:: examples/cpp/dht-kademlia/s4u-dht-kademlia.cpp
939 .. showfile:: examples/cpp/dht-kademlia/routing_table.cpp
942 .. showfile:: examples/cpp/dht-kademlia/answer.cpp
945 .. showfile:: examples/cpp/dht-kademlia/node.cpp
950 .. showfile:: examples/c/dht-kademlia/dht-kademlia.c
953 .. showfile:: examples/c/dht-kademlia/routing_table.c
956 .. showfile:: examples/c/dht-kademlia/answer.c
959 .. showfile:: examples/c/dht-kademlia/message.c
962 .. showfile:: examples/c/dht-kademlia/node.c
971 This example starts some computations both on PMs and VMs and
972 migrates some VMs around.
976 .. example-tab:: examples/cpp/cloud-simple/s4u-cloud-simple.cpp
978 .. example-tab:: examples/c/cloud-simple/cloud-simple.c
981 This example shows how to migrate VMs between PMs.
985 .. example-tab:: examples/cpp/cloud-migration/s4u-cloud-migration.cpp
987 .. example-tab:: examples/c/cloud-migration/cloud-migration.c
989 =======================
990 Model-Related Examples
991 =======================
993 - **ns-3 as a SimGrid Network Model**
994 This simple ping-pong example demonstrates how to use the bindings to the Network
995 Simulator. The most interesting is probably not the C++ files since
996 they are unchanged from the other simulations, but the associated files,
997 such as the platform file to see how to declare a platform to be used
998 with the ns-3 bindings of SimGrid and the tesh file to see how to
999 start a simulation in these settings.
1003 .. example-tab:: examples/cpp/network-ns3/s4u-network-ns3.cpp
1009 .. showfile:: examples/platforms/small_platform_one_link_routes.xml
1014 This demonstrates how to declare a wifi zone in your platform and
1015 how to use it in your simulation. For that, you should have a link
1016 whose sharing policy is set to `WIFI`. Such links can have more
1017 than one bandwidth value (separated by commas), corresponding to
1018 the several SNR level of your wifi link.
1020 In this case, SimGrid automatically switches to validated
1021 performance models of wifi networks, where the time is shared
1022 between users instead of the bandwidth for wired links (the
1023 corresponding publication is currently being written).
1025 If your wifi link provides more than one SNR level, you can switch
1026 the level of a given host using
1027 :cpp:func:`simgrid::s4u::Link::set_host_wifi_rate`. By default,
1028 the first level is used.
1032 .. example-tab:: examples/cpp/network-wifi/s4u-network-wifi.cpp
1038 .. showfile:: examples/platforms/wifi.xml
1045 It is possible to extend SimGrid without modifying its internals by
1046 attaching code to the existing signals and by adding extra data to the
1047 simulation objects through extensions. How to do that is not exactly
1048 documented yet, and you should look for examples in the src/plugins
1051 This section documents how the existing plugins can be used. Remember
1052 that you are very welcome to modify the plugins to fit your needs. It
1053 should be much easier than modifying the SimGrid kernel.
1055 - **Monitoring the host load**
1059 .. example-tab:: examples/cpp/plugin-host-load/s4u-plugin-host-load.cpp
1061 .. example-tab:: examples/c/plugin-host-load/plugin-host-load.c
1063 - **Monitoring the link load**
1067 .. example-tab:: examples/cpp/plugin-link-load/s4u-plugin-link-load.cpp
1069 =======================
1070 Model-Checking Examples
1071 =======================
1073 The model-checker can be used to exhaustively search for issues in the
1074 tested application. It must be activated at compile-time, but this
1075 mode is rather experimental in SimGrid (as of v3.25). You should not
1076 enable it unless you really want to formally verify your applications:
1077 SimGrid is slower and may be less robust when MC is enabled.
1079 - **Failing assert**
1080 In this example, two actors send some data to a central server,
1081 which asserts that the messages are always received in the same order.
1082 This is wrong, and the model-checker correctly finds a
1083 counter-example to that assertion.
1087 .. example-tab:: examples/cpp/mc-failing-assert/s4u-mc-failing-assert.cpp