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.
10 SimGrid comes with an extensive set of examples, documented on this
11 page. Most of them only demonstrate one single feature, with some
12 larger examplars listed below.
14 The C++ examples can be found under examples/s4u while python examples
15 are in examples/python. Each such directory contains the source code (also listed
16 from this page), and the so-called tesh file containing how to call
17 the binary obtained by compiling this example and also the expected
18 output. Tesh files are used to turn each of our examples into an
19 integration test. Some examples also contain other files, on need.
21 A good way to bootstrap your own project is to copy and combine some
22 of the provided examples to constitute the skeleton of what you plan
27 ===========================
28 Actors: the Active Entities
29 ===========================
31 Starting and Stoping Actors
32 ---------------------------
34 - **Creating actors:**
35 Most actors are started from the deployment XML file, because this
36 is a :ref:`better scientific habbit <howto_science>`, but you can
37 also create them directly from your code.
41 .. example-tab:: examples/s4u/actor-create/s4u-actor-create.cpp
43 You create actors either:
45 - Directly with :cpp:func:`simgrid::s4u::Actor::create`
46 - From XML with :cpp:func:`simgrid::s4u::Engine::register_actor` (if your actor is a class)
47 or :cpp:func:`simgrid::s4u::Engine::register_function` (if your actor is a function)
48 and then :cpp:func:`simgrid::s4u::Engine::load_deployment`
50 .. example-tab:: examples/python/actor-create/actor-create.py
52 You create actors either:
54 - Directly with :py:func:`simgrid.Actor.create()`
55 - From XML with :py:func:`simgrid.Engine.register_actor()` and then :py:func:`simgrid.Engine.load_deployment()`
57 .. example-tab:: examples/c/actor-create/actor-create.c
59 You create actors either:
61 - Directly with :cpp:func:`sg_actor_create()` followed by :cpp:func:`sg_actor_start`.
62 - From XML with :cpp:func:`simgrid_register_function` and then :cpp:func:`simgrid_load_deployment`.
64 .. example-tab:: examples/python/actor-create/actor-create_d.xml
66 The following file is used in both C++ and Python.
68 - **React to the end of actors:** You can attach callbacks to the end of
69 actors. There is several ways of doing so, depending on whether you want to
70 attach your callback to a given actor and on how you define the end of a
71 given actor. User code probably want to react to the termination of an actor
72 while some plugins want to react to the destruction (memory collection) of
77 .. example-tab:: examples/s4u/actor-exiting/s4u-actor-exiting.cpp
79 This example shows how to attach a callback to:
81 - the end of a specific actor: :cpp:func:`simgrid::s4u::this_actor::on_exit()`
82 - the end of any actor: :cpp:member:`simgrid::s4u::Actor::on_termination()`
83 - the destruction of any actor: :cpp:member:`simgrid::s4u::Actor::on_destruction()`
85 .. example-tab:: examples/c/actor-exiting/actor-exiting.c
87 This example shows how to attach a callback to the end of a specific actor with
88 :cpp:func:`sg_actor_on_exit()`.
91 Actors can forcefully stop other actors.
95 .. example-tab:: examples/s4u/actor-kill/s4u-actor-kill.cpp
97 See also :cpp:func:`void simgrid::s4u::Actor::kill(void)`, :cpp:func:`void simgrid::s4u::Actor::kill_all()`,
98 :cpp:func:`simgrid::s4u::this_actor::exit`, :cpp:func:`simgrid::s4u::this_actor::on_exit`.
100 .. example-tab:: examples/python/actor-kill/actor-kill.py
102 See also :py:func:`simgrid.Actor.kill`, :py:func:`simgrid.Actor.kill_all`, :py:func:`simgrid.this_actor.exit`,
103 :py:func:`simgrid.this_actor.on_exit`.
105 .. example-tab:: examples/c/actor-kill/actor-kill.c
107 See also :cpp:func:`sg_actor_kill`, :cpp:func:`sg_actor_kill_all`, :cpp:func:`sg_actor_exit`, :cpp:func:`sg_actor_on_exit`.
109 - **Controling the actor life cycle from the XML:**
110 You can specify a start time and a kill time in the deployment file.
114 .. example-tab:: examples/s4u/actor-lifetime/s4u-actor-lifetime.cpp
116 This file is not really interesting: the important matter is in the XML file.
118 .. example-tab:: examples/s4u/actor-lifetime/s4u-actor-lifetime_d.xml
120 This demonstrates the ``start_time`` and ``kill_time`` attribute of the :ref:`pf_tag_actor` tag.
122 .. example-tab:: examples/c/actor-lifetime/actor-lifetime.c
124 This file is not really interesting: the important matter is in the XML file.
126 - **Daemonize actors:**
127 Some actors may be intended to simulate daemons that run in background. This example show how to transform a regular
128 actor into a daemon that will be automatically killed once the simulation is over.
132 .. example-tab:: examples/s4u/actor-daemon/s4u-actor-daemon.cpp
134 See also :cpp:func:`simgrid::s4u::Actor::daemonize()` and :cpp:func:`simgrid::s4u::Actor::is_daemon()`.
136 .. example-tab:: examples/python/actor-daemon/actor-daemon.py
138 See also :py:func:`simgrid.Actor.daemonize()` and :py:func:`simgrid.Actor.is_daemon()`.
140 .. example-tab:: examples/c/actor-daemon/actor-daemon.c
142 See also :cpp:func:`sg_actor_daemonize` and :cpp:func:`sg_actor_is_daemon`.
144 - **Specify the stack size to use**
145 The stack size can be specified by default on the command line,
146 globally by changing the configuration with :cpp:func:`simgrid::s4u::Engine::set_config(std::string)`,
147 or for a specific actor using :cpp:func:`simgrid::s4u::Actor::set_stacksize` before its start.
151 .. example-tab:: examples/s4u/actor-stacksize/s4u-actor-stacksize.cpp
153 Inter-Actors Interactions
154 -------------------------
156 See also the examples on :ref:`inter-actors communications
157 <s4u_ex_communication>` and the ones on :ref:`classical
158 synchronization objects <s4u_ex_IPC>`.
160 - **Suspend and Resume actors:**
161 Actors can be suspended and resumed during their executions.
165 .. example-tab:: examples/s4u/actor-suspend/s4u-actor-suspend.cpp
167 See also :cpp:func:`simgrid::s4u::this_actor::suspend()`,
168 :cpp:func:`simgrid::s4u::Actor::suspend()`, :cpp:func:`simgrid::s4u::Actor::resume()`, and
169 :cpp:func:`simgrid::s4u::Actor::is_suspended()`.
171 .. example-tab:: examples/python/actor-suspend/actor-suspend.py
173 See also :py:func:`simgrid.this_actor.suspend()`,
174 :py:func:`simgrid.Actor.suspend()`, :py:func:`simgrid.Actor.resume()`, and
175 :py:func:`simgrid.Actor.is_suspended()`.
177 .. example-tab:: examples/c/actor-suspend/actor-suspend.c
179 See also :cpp:func:`sg_actor_suspend()`, :cpp:func:`sg_actor_resume()`, and
180 :cpp:func:`sg_actor_is_suspended()`.
182 - **Migrating Actors:**
183 Actors can move or be moved from a host to another very easily. It amount to setting them on a new host.
187 .. example-tab:: examples/s4u/actor-migrate/s4u-actor-migrate.cpp
189 See also :cpp:func:`simgrid::s4u::this_actor::set_host()` and :cpp:func:`simgrid::s4u::Actor::set_host()`.
191 .. example-tab:: examples/python/actor-migrate/actor-migrate.py
193 See also :py:func:`simgrid.this_actor.set_host()` and :py:func:`simgrid.Actor.set_host()`.
195 .. example-tab:: examples/c/actor-migrate/actor-migrate.c
197 See also :cpp:func:`sg_actor_set_host()`.
199 - **Waiting for the termination of an actor:** (joining on it)
200 You can block the current actor until the end of another actor.
204 .. example-tab:: examples/s4u/actor-join/s4u-actor-join.cpp
206 See also :cpp:func:`simgrid::s4u::Actor::join()`.
208 .. example-tab:: examples/python/actor-join/actor-join.py
210 See also :py:func:`simgrid.Actor.join()`.
212 .. example-tab:: examples/c/actor-join/actor-join.c
214 See also :cpp:func:`sg_actor_join`.
216 - **Yielding to other actors**.
217 The ```yield()``` function interrupts the execution of the current
218 actor, leaving a chance to the other actors that are ready to run
223 .. example-tab:: examples/s4u/actor-yield/s4u-actor-yield.cpp
225 See also :cpp:func:`simgrid::s4u::this_actor::yield()`.
227 .. example-tab:: examples/python/actor-yield/actor-yield.py
229 See also :py:func:`simgrid.this_actor.yield_()`.
231 .. example-tab:: examples/c/actor-yield/actor-yield.c
233 See also :cpp:func:`sg_actor_yield()`.
235 Traces Replay as a Workload
236 ---------------------------
238 This section details how to run trace-driven simulations. It is very
239 handy when you want to test an algorithm or protocol that only react
240 to external events. For example, many P2P protocols react to user
241 requests, but do nothing if there is no such event.
243 In such situations, you should write your protocol in C++, and separate
244 the workload that you want to play onto your protocol in a separate
245 text file. Declare a function handling each type of the events in your
246 trace, register them using :cpp:func:`xbt_replay_action_register()` in
247 your main, and then run the simulation.
249 Then, you can either have one trace file containing all your events,
250 or a file per simulated process: the former may be easier to work
251 with, but the second is more efficient on very large traces. Check
252 also the tesh files in the example directories for details.
254 - **Communication replay:**
255 Presents a set of event handlers reproducing classical communication
256 primitives (asynchronous send/receive at the moment).
260 .. example-tab:: examples/s4u/replay-comm/s4u-replay-comm.cpp
263 Presents a set of event handlers reproducing classical I/O
264 primitives (open, read, close).
268 .. example-tab:: examples/s4u/replay-io/s4u-replay-io.cpp
270 ==========================
271 Activities: what Actors do
272 ==========================
274 .. _s4u_ex_communication:
276 Communications on the Network
277 -----------------------------
279 - **Basic asynchronous communications:**
280 Illustrates how to have non-blocking communications, that are
281 communications running in the background leaving the process free
282 to do something else during their completion.
286 .. example-tab:: examples/s4u/async-wait/s4u-async-wait.cpp
288 See also :cpp:func:`simgrid::s4u::Mailbox::put_async()` and :cpp:func:`simgrid::s4u::Comm::wait()`.
290 .. example-tab:: examples/python/async-wait/async-wait.py
292 See also :py:func:`simgrid.Mailbox.put_async()` and :py:func:`simgrid.Comm.wait()`.
294 .. example-tab:: examples/c/async-wait/async-wait.c
296 See also :cpp:func:`sg_mailbox_put_async()` and :cpp:func:`sg_comm__wait()`.
298 - **Waiting for all communications in a set:**
299 The ``wait_all()`` function is useful when you want to block until
300 all activities in a given set have completed.
304 .. example-tab:: examples/s4u/async-waitall/s4u-async-waitall.cpp
306 See also :cpp:func:`simgrid::s4u::Comm::wait_all()`.
308 .. example-tab:: examples/python/async-waitall/async-waitall.py
310 See also :py:func:`simgrid.Comm.wait_all()`.
312 .. example-tab:: examples/c/async-waitall/async-waitall.c
314 See also :cpp:func:`sg_comm_wait_all()`.
316 - **Waiting for the first completed communication in a set:**
317 The ``wait_any()`` function is useful
318 when you want to block until one activity of the set completes, no
319 matter which terminates first.
323 .. example-tab:: examples/s4u/async-waitany/s4u-async-waitany.cpp
325 See also :cpp:func:`simgrid::s4u::Comm::wait_any()`.
327 .. example-tab:: examples/python/async-waitany/async-waitany.py
329 See also :py:func:`simgrid.Comm.wait_any()`.
331 .. example-tab:: examples/c/async-waitany/async-waitany.c
333 See also :cpp:func:`sg_comm_wait_any`.
335 .. _s4u_ex_execution:
337 Executions on the CPU
338 ---------------------
340 - **Basic execution:**
341 The computations done in your program are not reported to the
342 simulated world, unless you explicitly request the simulator to pause
343 the actor until a given amount of flops gets computed on its simulated
344 host. Some executions can be given an higher priority so that they
349 .. example-tab:: examples/s4u/exec-basic/s4u-exec-basic.cpp
351 See also :cpp:func:`void simgrid::s4u::this_actor::execute(double)`
352 and :cpp:func:`void simgrid::s4u::this_actor::execute(double, double)`.
354 .. example-tab:: examples/python/exec-basic/exec-basic.py
356 See also :py:func:`simgrid.this_actor.execute()`.
358 .. example-tab:: examples/c/exec-basic/exec-basic.c
360 See also :cpp:func:`void sg_actor_execute(double)`
361 and :cpp:func:`void sg_actor_execute_with_priority(double, double)`.
363 - **Asynchronous execution:**
364 You can start asynchronous executions, just like you would fire
369 .. example-tab:: examples/s4u/exec-async/s4u-exec-async.cpp
371 See also :cpp:func:`simgrid::s4u::this_actor::exec_init()`,
372 :cpp:func:`simgrid::s4u::Activity::start()`,
373 :cpp:func:`simgrid::s4u::Activity::wait()`,
374 :cpp:func:`simgrid::s4u::Activity::get_remaining()`,
375 :cpp:func:`simgrid::s4u::Exec::get_remaining_ratio()`,
376 :cpp:func:`simgrid::s4u::this_actor::exec_async()` and
377 :cpp:func:`simgrid::s4u::Activity::cancel()`.
379 .. example-tab:: examples/python/exec-async/exec-async.py
381 See also :py:func:`simgrid.this_actor::exec_init()`,
382 :py:func:`simgrid.Activity::start()`,
383 :py:func:`simgrid.Activity.wait()`,
384 :py:func:`simgrid.Activity.get_remaining()`,
385 :py:func:`simgrid.Exec.get_remaining_ratio()`,
386 :py:func:`simgrid.this_actor.exec_async()` and
387 :py:func:`simgrid.Activity.cancel()`.
389 - **Remote execution:**
390 You can start executions on remote hosts, or even change the host
391 on which they occur during their execution.
395 .. example-tab:: examples/s4u/exec-remote/s4u-exec-remote.cpp
397 See also :cpp:func:`simgrid::s4u::Exec::set_host()`.
399 .. example-tab:: examples/python/exec-remote/exec-remote.py
401 See also :py:func:`simgrid.Exec.set_host()`.
403 .. example-tab:: examples/c/exec-remote/exec-remote.c
405 See also :cpp:func:`sg_exec_set_host()`.
407 - **Parallel executions:**
408 These objects are convenient abstractions of parallel
409 computational kernels that span over several machines, such as a
410 PDGEM and the other ScaLAPACK routines. Note that this only works
411 with the "ptask_L07" host model (``--cfg=host/model:ptask_L07``).
415 .. example-tab:: examples/s4u/exec-ptask/s4u-exec-ptask.cpp
417 See also :cpp:func:`simgrid::s4u::this_actor::parallel_execute()`.
419 - **Using Pstates on a host:**
420 This example shows how define a set of pstates in the XML. The current pstate
421 of an host can then be accessed and changed from the program.
425 .. example-tab:: examples/s4u/exec-dvfs/s4u-exec-dvfs.cpp
427 See also :cpp:func:`simgrid::s4u::Host::get_pstate_speed` and :cpp:func:`simgrid::s4u::Host::set_pstate`.
429 .. example-tab:: examples/c/exec-dvfs/exec-dvfs.c
431 See also :cpp:func:`sg_host_get_pstate_speed` and :cpp:func:`sg_host_set_pstate`.
433 .. example-tab:: examples/python/exec-dvfs/exec-dvfs.py
435 See also :py:func:`Host.get_pstate_speed` and :py:func:`Host.set_pstate`.
437 .. example-tab:: examples/platforms/energy_platform.xml
441 I/O on Disks and Files
442 ----------------------
444 SimGrid provides two levels of abstraction to interact with the
445 simulated disks. At the simplest level, you simply create read and
446 write actions on the disk resources.
448 - **Access to raw disk devices:**
449 This example illustrates how to simply read and write data on a
450 simulated disk resource.
454 .. example-tab:: examples/s4u/io-disk-raw/s4u-io-disk-raw.cpp
456 .. example-tab:: examples/c/io-disk-raw/io-disk-raw.c
458 .. example-tab:: examples/platforms/hosts_with_disks.xml
460 This shows how to declare disks in XML.
462 The FileSystem plugin provides a more detailed view, with the
463 classical operations over files: open, move, unlink, and of course
464 read and write. The file and disk sizes are also dealt with and can
465 result in short reads and short write, as in reality.
467 - **File Management:**
468 This example illustrates the use of operations on files
469 (read, write, seek, tell, unlink, etc).
473 .. example-tab:: examples/s4u/io-file-system/s4u-io-file-system.cpp
476 I/O operations on files can also be done in a remote fashion,
477 i.e. when the accessed disk is not mounted on the caller's host.
481 .. example-tab:: examples/s4u/io-file-remote/s4u-io-file-remote.cpp
483 .. example-tab:: examples/c/io-file-remote/io-file-remote.c
487 Classical synchronization objects
488 ---------------------------------
491 Shows how to use :cpp:type:`simgrid::s4u::Barrier` synchronization objects.
495 .. example-tab:: examples/s4u/synchro-barrier/s4u-synchro-barrier.cpp
497 - **Condition variable:**
498 Shows how to use :cpp:type:`simgrid::s4u::ConditionVariable` synchronization objects.
502 .. example-tab:: examples/s4u/synchro-condition-variable/s4u-synchro-condition-variable.cpp
505 Shows how to use :cpp:type:`simgrid::s4u::Mutex` synchronization objects.
509 .. example-tab:: examples/s4u/synchro-mutex/s4u-synchro-mutex.cpp
512 Shows how to use :cpp:type:`simgrid::s4u::Semaphore` synchronization objects.
516 .. example-tab:: examples/s4u/synchro-semaphore/s4u-synchro-semaphore.cpp
518 =============================
519 Interacting with the Platform
520 =============================
522 - **User-defined properties:**
523 You can attach arbitrary information to most platform elements from
524 the XML file, and then interact with these values from your
525 program. Note that the changes are not written permanently on disk,
526 in the XML file nor anywhere else. They only last until the end of
531 .. example-tab:: examples/s4u/platform-properties/s4u-platform-properties.cpp
533 - :cpp:func:`simgrid::s4u::Actor::get_property()` and :cpp:func:`simgrid::s4u::Actor::set_property()`
534 - :cpp:func:`simgrid::s4u::Host::get_property()` and :cpp:func:`simgrid::s4u::Host::set_property()`
535 - :cpp:func:`simgrid::s4u::Link::get_property()` and :cpp:func:`simgrid::s4u::Link::set_property()`
536 - :cpp:func:`simgrid::s4u::NetZone::get_property()` and :cpp:func:`simgrid::s4u::NetZone::set_property()`
542 .. showfile:: examples/s4u/platform-properties/s4u-platform-properties_d.xml
548 .. showfile:: examples/platforms/prop.xml
551 - **Retrieving the netzones matching a given criteria:**
552 Shows how to filter the cluster netzones.
556 .. example-tab:: examples/s4u/routing-get-clusters/s4u-routing-get-clusters.cpp
558 - **Retrieving the list of hosts matching a given criteria:**
559 Shows how to filter the actors that match a given criteria.
563 .. example-tab:: examples/s4u/engine-filtering/s4u-engine-filtering.cpp
565 - **Specifying state profiles:** shows how to specify when the
566 resources must be turned off and on again, and how to react to such
567 failures in your code. See also :ref:`howto_churn`.
571 .. example-tab:: examples/s4u/platform-failures/s4u-platform-failures.cpp
575 .. showfile:: examples/platforms/small_platform_failures.xml
578 .. showfile:: examples/platforms/profiles/jupiter_state.profile
580 .. showfile:: examples/platforms/profiles/bourassa_state.profile
582 .. showfile:: examples/platforms/profiles/fafard_state.profile
584 - **Specifying speed profiles:** shows how to specify an external
585 load to resources, variating their peak speed over time.
589 .. example-tab:: examples/s4u/platform-profile/s4u-platform-profile.cpp
593 .. showfile:: examples/platforms/small_platform_profile.xml
596 .. showfile:: examples/platforms/profiles/jupiter_speed.profile
598 .. showfile:: examples/platforms/profiles/link1_bandwidth.profile
600 .. showfile:: examples/platforms/profiles/link1_latency.profile
606 - **Describing the energy profiles in the platform:**
607 This platform file contains the energy profile of each links and
608 hosts, which is necessary to get energy consumption predictions.
609 As usual, you should not trust our example, and you should strive
610 to double-check that your instantiation matches your target platform.
614 .. example-tab:: examples/platforms/energy_platform.xml
616 - **Consumption due to the CPU:**
617 This example shows how to retrieve the amount of energy consumed
618 by the CPU during computations, and the impact of the pstate.
622 .. example-tab:: examples/s4u/energy-exec/s4u-energy-exec.cpp
624 .. example-tab:: examples/c/energy-exec/energy-exec.c
626 - **Consumption due to the network:**
627 This example shows how to retrieve and display the energy consumed
628 by the network during communications.
632 .. example-tab:: examples/s4u/energy-link/s4u-energy-link.cpp
634 - **Modeling the shutdown and boot of hosts:**
635 Simple example of model of model for the energy consumption during
636 the host boot and shutdown periods.
640 .. example-tab:: examples/s4u/energy-boot/platform_boot.xml
642 .. example-tab:: examples/s4u/energy-boot/s4u-energy-boot.cpp
644 =======================
645 Tracing and Visualizing
646 =======================
648 Tracing can be activated by various configuration options which
649 are illustrated in these example. See also the
650 :ref:`full list of options related to tracing <tracing_tracing_options>`.
652 It is interesting to run the process-create example with the following
653 options to see the task executions:
655 - **Platform Tracing:**
656 This program is a toy example just loading the platform, so that
657 you can play with the platform visualization. Recommanded options:
658 ``--cfg=tracing:yes --cfg=tracing/categorized:yes``
662 .. example-tab:: examples/s4u/trace-platform/s4u-trace-platform.cpp
664 ========================
665 Larger SimGrid Examplars
666 ========================
668 This section contains application examples that are somewhat larger
669 than the previous examples.
672 This simple example just sends one message back and forth.
673 The tesh file laying in the directory show how to start the simulator binary, highlighting how to pass options to
674 the simulators (as detailed in Section :ref:`options`).
678 .. example-tab:: examples/s4u/app-pingpong/s4u-app-pingpong.cpp
680 .. example-tab:: examples/c/app-pingpong/app-pingpong.c
683 Shows how to implement a classical communication pattern, where a
684 token is exchanged along a ring to reach every participant.
688 .. example-tab:: examples/s4u/app-token-ring/s4u-app-token-ring.cpp
690 .. example-tab:: examples/c/app-token-ring/app-token-ring.c
692 - **Master Workers:**
693 Another good old example, where one Master process has a bunch of task to dispatch to a set of several Worker
700 This example comes in two equivalent variants, one where the actors
701 are specified as simple functions (which is easier to understand for
702 newcomers) and one where the actors are specified as classes (which is
703 more powerful for the users wanting to build their own projects upon
706 .. showfile:: examples/s4u/app-masterworkers/s4u-app-masterworkers-class.cpp
709 .. showfile:: examples/s4u/app-masterworkers/s4u-app-masterworkers-fun.cpp
716 Classical protocol for Peer-to-Peer data diffusion.
722 .. showfile:: examples/s4u/app-bittorrent/s4u-bittorrent.cpp
725 .. showfile:: examples/s4u/app-bittorrent/s4u-peer.cpp
728 .. showfile:: examples/s4u/app-bittorrent/s4u-tracker.cpp
732 Data broadcast over a ring of processes.
736 .. example-tab:: examples/s4u/app-chainsend/s4u-app-chainsend.cpp
740 .. showfile:: examples/c/app-chainsend/chainsend.c
743 .. showfile:: examples/c/app-chainsend/broadcaster.c
746 .. showfile:: examples/c/app-chainsend/peer.c
749 Distributed Hash Tables (DHT)
750 -----------------------------
753 One of the most famous DHT protocol.
759 .. showfile:: examples/s4u/dht-chord/s4u-dht-chord.cpp
762 .. showfile:: examples/s4u/dht-chord/s4u-dht-chord-node.cpp
766 Another well-known DHT protocol.
772 .. showfile:: examples/s4u/dht-kademlia/s4u-dht-kademlia.cpp
775 .. showfile:: examples/s4u/dht-kademlia/routing_table.cpp
778 .. showfile:: examples/s4u/dht-kademlia/answer.cpp
781 .. showfile:: examples/s4u/dht-kademlia/node.cpp
790 This example starts some computations both on PMs and VMs, and
791 migrates some VMs around.
795 .. example-tab:: examples/s4u/cloud-simple/s4u-cloud-simple.cpp
797 .. example-tab:: examples/c/cloud-simple/cloud-simple.c
800 This example shows how to migrate VMs between PMs.
804 .. example-tab:: examples/s4u/cloud-migration/s4u-cloud-migration.cpp
806 .. example-tab:: examples/c/cloud-migration/cloud-migration.c
808 =======================
809 Model-Checking Examples
810 =======================
812 The model-checker can be used to exhaustively search for issues in the
813 tested application. It must be activated at compile time, but this
814 mode is rather experimental in SimGrid (as of v3.22). You should not
815 enable it unless you really want to formally verify your applications:
816 SimGrid is slower and maybe less robust when MC is enabled.
819 In this example, two actors send some data to a central server,
820 which asserts that the messages are always received in the same order.
821 This is obviously wrong, and the model-checker correctly finds a
822 counter-example to that assertion.
826 .. example-tab:: examples/s4u/mc-failing-assert/s4u-mc-failing-assert.cpp
832 .. |cpp| image:: /img/lang_cpp.png
836 .. |py| image:: /img/lang_python.png