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/platforms/prop.xml
621 - **Retrieving the netzones matching given criteria:**
622 Shows how to filter the cluster netzones.
626 .. example-tab:: examples/cpp/routing-get-clusters/s4u-routing-get-clusters.cpp
628 - **Retrieving the list of hosts matching given criteria:**
629 Shows how to filter the actors that match given criteria.
633 .. example-tab:: examples/cpp/engine-filtering/s4u-engine-filtering.cpp
635 - **Specifying state profiles:** shows how to specify when the
636 resources must be turned off and on again, and how to react to such
637 failures in your code. See also :ref:`howto_churn`.
641 .. example-tab:: examples/cpp/platform-failures/s4u-platform-failures.cpp
643 .. example-tab:: examples/c/platform-failures/platform-failures.c
647 .. showfile:: examples/platforms/small_platform_failures.xml
650 .. showfile:: examples/platforms/profiles/jupiter_state.profile
652 .. showfile:: examples/platforms/profiles/fafard_state.profile
654 - **Specifying speed profiles:** shows how to specify an external
655 load to resources, variating their peak speed over time.
659 .. example-tab:: examples/cpp/platform-profile/s4u-platform-profile.cpp
663 .. showfile:: examples/platforms/small_platform_profile.xml
666 .. showfile:: examples/platforms/profiles/jupiter_speed.profile
668 .. showfile:: examples/platforms/profiles/link1_bandwidth.profile
670 .. showfile:: examples/platforms/profiles/link1_latency.profile
676 - **Describing the energy profiles in the platform:**
677 The first platform file contains the energy profile of each link and
678 host for a wired network, which is necessary to get energy consumption
679 predictions. The second platform file is the equivalent for a wireless
680 network. As usual, you should not trust our example, and you should
681 strive to double-check that your instantiation matches your target
688 .. showfile:: examples/platforms/energy_platform.xml
691 .. showfile:: examples/platforms/wifi_energy.xml
694 - **Consumption due to the CPU:**
695 This example shows how to retrieve the amount of energy consumed
696 by the CPU during computations, and the impact of the pstate.
700 .. example-tab:: examples/cpp/energy-exec/s4u-energy-exec.cpp
702 .. example-tab:: examples/c/energy-exec/energy-exec.c
704 - **Consumption due to the wired network:**
705 This example shows how to retrieve and display the energy consumed
706 by the wired network during communications.
710 .. example-tab:: examples/cpp/energy-link/s4u-energy-link.cpp
712 - **Consumption due to the wireless network:**
713 This example shows how to retrieve and display the energy consumed
714 by the wireless network during communications.
718 .. example-tab:: examples/cpp/energy-wifi/s4u-energy-wifi.cpp
720 - **Modeling the shutdown and boot of hosts:**
721 Simple example of a model for the energy consumption during
722 the host boot and shutdown periods.
726 .. example-tab:: examples/cpp/energy-boot/platform_boot.xml
728 .. example-tab:: examples/cpp/energy-boot/s4u-energy-boot.cpp
730 =======================
731 Tracing and Visualizing
732 =======================
734 Tracing can be activated by various configuration options which
735 are illustrated in these examples. See also the
736 :ref:`full list of options related to tracing <tracing_tracing_options>`.
738 It is interesting to run the process-create example with the following
739 options to see the task executions:
741 - **Platform Tracing:**
742 This program is a toy example just loading the platform so that
743 you can play with the platform visualization. Recommended options:
744 ``--cfg=tracing:yes --cfg=tracing/categorized:yes``
748 .. example-tab:: examples/cpp/trace-platform/s4u-trace-platform.cpp
750 - **Setting Categories**
751 This example declares several tracing categories that are used to
752 classify its tasks. When the program is executed, the tracing mechanism
753 registers the resource utilization of hosts and links according to these
754 categories. Recommended options:
755 ``--cfg=tracing:yes --cfg=tracing/categorized:yes --cfg=tracing/uncategorized:yes``
759 .. example-tab:: examples/cpp/trace-categories/s4u-trace-categories.cpp
761 - **Master Workers tracing**
762 This is an augmented version of our basic master/worker example using
763 several tracing features. It traces resource usage, sorted out in several
764 categories; Trace marks and user variables are also used. Recommended
765 options: ``--cfg=tracing/categorized:yes --cfg=tracing/uncategorized:yes``
769 .. example-tab:: examples/cpp/trace-masterworkers/s4u-trace-masterworkers.cpp
771 - **Process migration tracing**
772 This version is enhanced so that the process migrations can be displayed
773 as arrows in a Gantt-chart visualization. Recommended options to that
774 extend: ``--cfg=tracing:yes --cfg=tracing/actor:yes``
778 .. example-tab:: examples/cpp/trace-process-migration/s4u-trace-process-migration.cpp
781 TODO: These tracing examples should be integrated in the examples to not
782 duplicate the C++ files. A full command line to see the result in the right
783 tool (vite/FrameSoc) should be given along with some screenshots.
785 Tracing user variables
786 ----------------------
788 You can also attach your own variables to any resource described in the platform
789 file. The following examples illustrate this feature. They have to be run with
790 the following options: ``--cfg=tracing:yes --cfg=tracing/platform:yes``
792 - **Attaching variables to Hosts**
796 .. example-tab:: examples/cpp/trace-host-user-variables/s4u-trace-host-user-variables.cpp
798 - **Attaching variables to Links**
799 The tricky part is that you have to know the name of the link you want to
800 enhance with a variable.
804 .. example-tab:: examples/cpp/trace-link-user-variables/s4u-trace-link-user-variables.cpp
806 - **Attaching variables to network Routes**
807 It is often easier to update a given variable for all links of a given
808 network path (identified by its source and destination hosts) instead of
809 knowing the name of each specific link.
813 .. example-tab:: examples/cpp/trace-route-user-variables/s4u-trace-route-user-variables.cpp
815 ========================
816 Larger SimGrid Exemplars
817 ========================
819 This section contains application examples that are somewhat larger
820 than the previous examples.
823 Shows how to implement a classical communication pattern, where a
824 token is exchanged along a ring to reach every participant.
828 .. example-tab:: examples/cpp/app-token-ring/s4u-app-token-ring.cpp
830 .. example-tab:: examples/c/app-token-ring/app-token-ring.c
832 - **Master Workers:**
833 Another good old example, where one Master process has a bunch of tasks to dispatch to a set of several Worker
840 This example comes in two equivalent variants, one where the actors
841 are specified as simple functions (which is easier to understand for
842 newcomers) and one where the actors are specified as classes (which is
843 more powerful for the users wanting to build their own projects upon
846 .. showfile:: examples/cpp/app-masterworkers/s4u-app-masterworkers-class.cpp
849 .. showfile:: examples/cpp/app-masterworkers/s4u-app-masterworkers-fun.cpp
854 .. showfile:: examples/c/app-masterworker/app-masterworker.c
861 Classical protocol for Peer-to-Peer data diffusion.
867 .. showfile:: examples/cpp/app-bittorrent/s4u-bittorrent.cpp
870 .. showfile:: examples/cpp/app-bittorrent/s4u-peer.cpp
873 .. showfile:: examples/cpp/app-bittorrent/s4u-tracker.cpp
878 .. showfile:: examples/c/app-bittorrent/app-bittorrent.c
881 .. showfile:: examples/c/app-bittorrent/bittorrent-peer.c
884 .. showfile:: examples/c/app-bittorrent/tracker.c
888 Data broadcast over a ring of processes.
892 .. example-tab:: examples/cpp/app-chainsend/s4u-app-chainsend.cpp
896 .. showfile:: examples/c/app-chainsend/chainsend.c
899 .. showfile:: examples/c/app-chainsend/broadcaster.c
902 .. showfile:: examples/c/app-chainsend/peer.c
905 Distributed Hash Tables (DHT)
906 -----------------------------
909 One of the most famous DHT protocol.
915 .. showfile:: examples/cpp/dht-chord/s4u-dht-chord.cpp
918 .. showfile:: examples/cpp/dht-chord/s4u-dht-chord-node.cpp
922 Another well-known DHT protocol.
928 .. showfile:: examples/cpp/dht-kademlia/s4u-dht-kademlia.cpp
931 .. showfile:: examples/cpp/dht-kademlia/routing_table.cpp
934 .. showfile:: examples/cpp/dht-kademlia/answer.cpp
937 .. showfile:: examples/cpp/dht-kademlia/node.cpp
942 .. showfile:: examples/c/dht-kademlia/dht-kademlia.c
945 .. showfile:: examples/c/dht-kademlia/routing_table.c
948 .. showfile:: examples/c/dht-kademlia/answer.c
951 .. showfile:: examples/c/dht-kademlia/message.c
954 .. showfile:: examples/c/dht-kademlia/node.c
963 This example starts some computations both on PMs and VMs and
964 migrates some VMs around.
968 .. example-tab:: examples/cpp/cloud-simple/s4u-cloud-simple.cpp
970 .. example-tab:: examples/c/cloud-simple/cloud-simple.c
973 This example shows how to migrate VMs between PMs.
977 .. example-tab:: examples/cpp/cloud-migration/s4u-cloud-migration.cpp
979 .. example-tab:: examples/c/cloud-migration/cloud-migration.c
981 =======================
982 Model-Related Examples
983 =======================
985 - **ns-3 as a SimGrid Network Model**
986 This simple ping-pong example demonstrates how to use the bindings to the Network
987 Simulator. The most interesting is probably not the C++ files since
988 they are unchanged from the other simulations, but the associated files,
989 such as the platform file to see how to declare a platform to be used
990 with the ns-3 bindings of SimGrid and the tesh file to see how to
991 start a simulation in these settings.
995 .. example-tab:: examples/cpp/network-ns3/s4u-network-ns3.cpp
1001 .. showfile:: examples/platforms/small_platform_one_link_routes.xml
1006 This demonstrates how to declare a wifi zone in your platform and
1007 how to use it in your simulation. For that, you should have a link
1008 whose sharing policy is set to `WIFI`. Such links can have more
1009 than one bandwidth value (separated by commas), corresponding to
1010 the several SNR level of your wifi link.
1012 In this case, SimGrid automatically switches to validated
1013 performance models of wifi networks, where the time is shared
1014 between users instead of the bandwidth for wired links (the
1015 corresponding publication is currently being written).
1017 If your wifi link provides more than one SNR level, you can switch
1018 the level of a given host using
1019 :cpp:func:`simgrid::s4u::Link::set_host_wifi_rate`. By default,
1020 the first level is used.
1024 .. example-tab:: examples/cpp/network-wifi/s4u-network-wifi.cpp
1030 .. showfile:: examples/platforms/wifi.xml
1037 It is possible to extend SimGrid without modifying its internals by
1038 attaching code to the existing signals and by adding extra data to the
1039 simulation objects through extensions. How to do that is not exactly
1040 documented yet, and you should look for examples in the src/plugins
1043 This section documents how the existing plugins can be used. Remember
1044 that you are very welcome to modify the plugins to fit your needs. It
1045 should be much easier than modifying the SimGrid kernel.
1047 - **Monitoring the host load**
1051 .. example-tab:: examples/cpp/plugin-host-load/s4u-plugin-host-load.cpp
1053 .. example-tab:: examples/c/plugin-host-load/plugin-host-load.c
1055 - **Monitoring the link load**
1059 .. example-tab:: examples/cpp/plugin-link-load/s4u-plugin-link-load.cpp
1061 =======================
1062 Model-Checking Examples
1063 =======================
1065 The model-checker can be used to exhaustively search for issues in the
1066 tested application. It must be activated at compile-time, but this
1067 mode is rather experimental in SimGrid (as of v3.25). You should not
1068 enable it unless you really want to formally verify your applications:
1069 SimGrid is slower and may be less robust when MC is enabled.
1071 - **Failing assert**
1072 In this example, two actors send some data to a central server,
1073 which asserts that the messages are always received in the same order.
1074 This is wrong, and the model-checker correctly finds a
1075 counter-example to that assertion.
1079 .. example-tab:: examples/cpp/mc-failing-assert/s4u-mc-failing-assert.cpp