1 .. S4U (Simgrid for you) is the next interface of SimGrid, expected to be released with SimGrid 4.0.
3 .. Even if it is not completely rock stable yet, it may well already fit
4 .. your needs. You are welcome to try it and report any interface
5 .. glitches that you see. Be however warned that the interface may change
6 .. until the final release. You will have to adapt your code on the way.
8 .. This file follows the ReStructured syntax to be included in the
9 .. documentation, but it should remain readable directly.
15 SimGrid comes with an extensive set of examples, documented on this
16 page. Most of them only demonstrate one single feature, with some
17 larger examplars listed below.
19 The C++ examples can be found under examples/s4u while python examples
20 are in examples/python. Each such directory contains the source code (also listed
21 from this page), and the so-called tesh file containing how to call
22 the binary obtained by compiling this example and also the expected
23 output. Tesh files are used to turn each of our examples into an
24 integration test. Some examples also contain other files, on need.
26 A good way to bootstrap your own project is to copy and combine some
27 of the provided examples to constitute the skeleton of what you plan
30 ===========================
31 Actors: the Active Entities
32 ===========================
35 Starting and Stoping Actors
36 ---------------------------
38 - **Creating actors:**
39 Most actors are started from the deployment XML file, but there is other methods.
40 This example show them all.
41 |br| |cpp| `examples/s4u/actor-create/s4u-actor-create.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-create/s4u-actor-create.cpp>`_
42 |br| |py| `examples/python/actor-create/actor-create.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/actor-create/actor-create.py>`_
45 Actors can forcefully stop other actors with the
46 :cpp:func:`void simgrid::s4u::Actor::kill(void)` or the
47 :cpp:func:`void simgrid::s4u::Actor::kill(aid_t)` methods.
48 |br| `examples/s4u/actor-kill/s4u-actor-kill.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-kill/s4u-actor-kill.cpp>`_
50 - **Controling the actor life cycle from the XML:**
51 You can specify a start time and a kill time in the deployment
53 |br| `examples/s4u/actor-lifetime/s4u-actor-lifetime.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-lifetime/s4u-actor-lifetime.cpp>`_
54 |br| `examples/s4u/actor-lifetime/s4u-actor-lifetime_d.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-lifetime/s4u-actor-lifetime_d.xml>`_
56 - **Daemonize actors:**
57 Some actors may be intended to simulate daemons that run in background. This example show how to transform a regular
58 actor into a daemon that will be automatically killed once the simulation is over.
59 |br| `examples/s4u/actor-daemon/s4u-actor-daemon.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-daemon/s4u-actor-daemon.cpp>`_
61 Inter-Actors Interactions
62 -------------------------
64 - **Suspend and Resume actors:**
65 Actors can be suspended and resumed during their executions thanks
66 to :cpp:func:`simgrid::s4u::Actor::suspend()` and
67 :cpp:func:`simgrid::s4u::Actor::resume()`.
68 |br| `examples/s4u/actor-suspend/s4u-actor-suspend.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-suspend/s4u-actor-suspend.cpp>`_
70 - **Migrating Actors:**
71 Actors can move or be moved from a host to another very easily.
72 |br| |cpp| `examples/s4u/actor-migrate/s4u-actor-migrate.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-migrate/s4u-actor-migrate.cpp>`_
73 :cpp:func:`simgrid::s4u::this_actor::migrate()` |cpp|
74 |br| |py| `examples/python/actor-migrate/actor-migrate.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/actor-migrate/actor-migrate.py>`_
75 :py:func:`simgrid.this_actor.migrate()` |py|
77 - **Waiting for the termination of an actor:** (joining on it)
78 You can block the current actor until the end of another actor.
79 |br| |cpp| `examples/s4u/actor-join/s4u-actor-join.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-join/s4u-actor-join.cpp>`_
80 :cpp:func:`simgrid::s4u::Actor::join()` |cpp|
81 |br| |py| `examples/python/actor-join/actor-join.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/actor-join/actor-join.py>`_
82 :py:func:`simgrid.Actor.join()` |py|
84 - **Yielding to other actors**.
85 The ```yield()``` function interrupts the execution of the current
86 actor, leaving a chance to the other actors that are ready to run
88 |br| |cpp| `examples/s4u/actor-yield/s4u-actor-yield.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-yield/s4u-actor-yield.cpp>`_
89 :cpp:func:`simgrid::s4u::this_actor::yield()` |cpp|
90 |br| |py| `examples/python/actor-yield/actor-yield.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/actor-yield/actor-yield.py>`_
91 :py:func:`simgrid.this_actor.yield_()` |py|
93 Traces Replay as a Workload
94 ---------------------------
96 This section details how to run trace-driven simulations. It is very
97 handy when you want to test an algorithm or protocol that only react
98 to external events. For example, many P2P protocols react to user
99 requests, but do nothing if there is no such event.
101 In such situations, you should write your protocol in C++, and separate
102 the workload that you want to play onto your protocol in a separate
103 text file. Declare a function handling each type of the events in your
104 trace, register them using :cpp:func:`xbt_replay_action_register()` in
105 your main, and then run the simulation.
107 Then, you can either have one trace file containing all your events,
108 or a file per simulated process: the former may be easier to work
109 with, but the second is more efficient on very large traces. Check
110 also the tesh files in the example directories for details.
112 - **Communication replay:**
113 Presents a set of event handlers reproducing classical communication
114 primitives (asynchronous send/receive at the moment).
115 |br| `examples/s4u/replay-comm/s4u-replay-comm.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/replay-comm/s4u-replay-comm.cpp>`_
118 Presents a set of event handlers reproducing classical I/O
119 primitives (open, read, close).
120 |br| `examples/s4u/replay-storage/s4u-replay-storage.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/replay-storage/s4u-replay-storage.cpp>`_
122 ==========================
123 Activities: what Actors do
124 ==========================
126 Communications on the Network
127 -----------------------------
129 - **Basic asynchronous communications:**
130 Illustrates how to have non-blocking communications, that are
131 communications running in the background leaving the process free
132 to do something else during their completion. The main functions
133 involved are :cpp:func:`simgrid::s4u::Mailbox::put_async()` and
134 :cpp:func:`simgrid::s4u::Comm::wait()`.
135 |br| `examples/s4u/async-wait/s4u-async-wait.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-wait/s4u-async-wait.cpp>`_
137 - **Waiting for all communications in a set:**
138 The :cpp:func:`simgrid::s4u::Comm::wait_all()` function is useful
139 when you want to block until all activities in a given set have
141 |br| `examples/s4u/async-waitall/s4u-async-waitall.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-waitall/s4u-async-waitall.cpp>`_
143 - **Waiting for the first completed communication in a set:**
144 The :cpp:func:`simgrid::s4u::Comm::wait_any()` function is useful
145 when you want to block until one activity of the set completes, no
146 matter which terminates first.
147 |br| `examples/s4u/async-waitany/s4u-async-waitany.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-waitany/s4u-async-waitany.cpp>`_
149 .. todo:: add the `ready` example here
151 .. _s4u_ex_execution:
153 Executions on the CPU
154 ---------------------
156 - **Basic execution:**
157 The computations done in your program are not reported to the
158 simulated world, unless you explicitely request the simulator to pause
159 the actor until a given amount of flops gets computed on its simulated
160 host. Some executions can be given an higher priority so that they
162 |br| |cpp| `examples/s4u/exec-basic/s4u-exec-basic.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-basic/s4u-exec-basic.cpp>`_
163 |br| |py| `examples/python/exec-basic/exec-basic.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/exec-basic/exec-basic.py>`_
165 - **Asynchronous execution:**
166 You can start asynchronous executions, just like you would fire
168 |br| `examples/s4u/exec-async/s4u-exec-async.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-async/s4u-exec-async.cpp>`_
170 - **Monitoring asynchronous executions:**
171 This example shows how to start an asynchronous execution, and
173 |br| `examples/s4u/exec-monitor/s4u-exec-monitor.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-monitor/s4u-exec-monitor.cpp>`_
175 - **Remote execution:**
176 Before its start, you can change the host on which a given execution will occur.
177 |br| `examples/s4u/exec-remote/s4u-exec-remote.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-remote/s4u-exec-remote.cpp>`_
179 - **Using Pstates on a host:**
180 Shows how define a set of pstatesfor a host in the XML, and how the current
181 pstate can be accessed/changed with :cpp:func:`simgrid::s4u::Host::get_pstate_speed` and :cpp:func:`simgrid::s4u::Host::set_pstate`.
182 |br| `examples/s4u/exec-dvfs/s4u-exec-dvfs.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-dvfs/s4u-exec-dvfs.cpp>`_
183 |br| `examples/platforms/energy_platform.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/energy_platform.xml>`_
185 - **Parallel executions:**
186 These objects are convenient abstractions of parallel
187 computational kernels that span over several machines, such as a
188 PDGEM and the other ScaLAPACK routines.
189 |br| `examples/s4u/exec-ptask/s4u-exec-ptask.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-ptask/s4u-exec-ptask.cpp>`_
191 I/O on Disks and Files
192 ----------------------
194 SimGrid provides two levels of abstraction to interact with the
195 simulated storages. At the simplest level, you simply create read and
196 write actions on the storage resources.
198 - **Access to raw storage devices:**
199 This example illustrates how to simply read and write data on a
200 simulated storage resource.
201 |br| `examples/s4u/io-storage-raw/s4u-io-storage-raw.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/io-storage-raw/s4u-io-storage-raw.cpp>`_
203 The FileSystem plugin provides a more detailed view, with the
204 classical operations over files: open, move, unlink, and of course
205 read and write. The file and disk sizes are also dealt with and can
206 result in short reads and short write, as in reality.
208 - **File Management:**
209 This example illustrates the use of operations on files
210 (read, write, seek, tell, unlink, etc).
211 |br| `examples/s4u/io-file-system/s4u-io-file-system.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/io-file-system/s4u-io-file-system.cpp>`_
214 I/O operations on files can also be done in a remote fashion,
215 i.e. when the accessed disk is not mounted on the caller's host.
216 |br| `examples/s4u/io-file-remote/s4u-io-file-remote.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/io-file-remote/s4u-io-file-remote.cpp>`_
218 Classical synchronization objects
219 ---------------------------------
222 Shows how to use simgrid::s4u::Mutex synchronization objects.
223 |br| `examples/s4u/synchro-mutex/s4u-synchro-mutex.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-mutex/s4u-synchro-mutex.cpp>`_
226 Shows how to use simgrid::s4u::Barrier synchronization objects.
227 |br| `examples/s4u/synchro-barrier/s4u-synchro-barrier.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-barrier/s4u-synchro-barrier.cpp>`_
230 Shows how to use simgrid::s4u::Semaphore synchronization objects.
231 |br| `examples/s4u/synchro-semaphore/s4u-synchro-semaphore.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-semaphore/s4u-synchro-semaphore.cpp>`_
233 =============================
234 Interacting with the Platform
235 =============================
237 - **Retrieving the list of hosts matching a given criteria:**
238 Shows how to filter the actors that match a given criteria.
239 |br| `examples/s4u/engine-filtering/s4u-engine-filtering.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/engine-filtering/s4u-engine-filtering.cpp>`_
241 - **User-defined properties:**
242 You can attach arbitrary information to most platform elements from
243 the XML file, and then interact with these values from your
244 program. Note that the changes are not written permanently on disk,
245 in the XML file nor anywhere else. They only last until the end of
248 - :cpp:func:`simgrid::s4u::Actor::get_property()` and :cpp:func:`simgrid::s4u::Actor::set_property()`
249 - :cpp:func:`simgrid::s4u::Host::get_property()` and :cpp:func:`simgrid::s4u::Host::set_property()`
250 - :cpp:func:`simgrid::s4u::Link::get_property()` and :cpp:func:`simgrid::s4u::Link::set_property()`
251 - :cpp:func:`simgrid::s4u::NetZone::get_property()` and :cpp:func:`simgrid::s4u::NetZone::set_property()`
253 |br| `examples/s4u/platform-properties/s4u-platform-properties.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/platform-properties/s4u-platform-properties.cpp>`_
254 |br| `examples/s4u/platform-properties/s4u-platform-properties_d.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/platform-properties/s4u-platform-properties_d.xml>`_
255 |br| `examples/platforms/prop.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/prop.xml>`_
261 - **Describing the energy profiles in the platform:**
262 This platform file contains the energy profile of each links and
263 hosts, which is necessary to get energy consumption predictions.
264 As usual, you should not trust our example, and you should strive
265 to double-check that your instanciation matches your target platform.
266 |br| `examples/platforms/energy_platform.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/energy_platform.xml>`_
268 - **Consumption due to the CPU:**
269 This example shows how to retrieve the amount of energy consumed
270 by the CPU during computations, and the impact of the pstate.
271 |br| `examples/s4u/energy-exec/s4u-energy-exec.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-exec/s4u-energy-exec.cpp>`_
273 - **Consumption due to the network:**
274 This example shows how to retrieve and display the energy consumed
275 by the network during communications.
276 |br| `examples/s4u/energy-link/s4u-energy-link.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-link/s4u-energy-link.cpp>`_
278 - **Modeling the shutdown and boot of hosts:**
279 Simple example of model of model for the energy consumption during
280 the host boot and shutdown periods.
281 |br| `examples/s4u/energy-boot/platform_boot.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-boot/platform_boot.xml>`_
282 |br| `examples/s4u/energy-boot/s4u-energy-boot.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-boot/s4u-energy-boot.cpp>`_
284 =======================
285 Tracing and Visualizing
286 =======================
288 Tracing can be activated by various configuration options which
289 are illustrated in these example. See also the
290 :ref:`full list of options related to tracing <tracing_tracing_options>`.
292 It is interesting to run the process-create example with the following
293 options to see the task executions:
295 - **Platform Tracing:**
296 This program is a toy example just loading the platform, so that
297 you can play with the platform visualization. Recommanded options:
298 ``--cfg=tracing:yes --cfg=tracing/categorized:yes``
299 |br| `examples/s4u/trace-platform/s4u-trace-platform.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/trace-platform/s4u-trace-platform.cpp>`_
301 ========================
302 Larger SimGrid Examplars
303 ========================
305 This section contains application examples that are somewhat larger
306 than the previous examples.
309 This simple example just sends one message back and forth.
310 The tesh file laying in the directory show how to start the simulator binary, highlighting how to pass options to
311 the simulators (as detailed in Section :ref:`options`).
312 |br| `examples/s4u/app-pingpong/s4u-app-pingpong.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-pingpong/s4u-app-pingpong.cpp>`_
315 Shows how to implement a classical communication pattern, where a
316 token is exchanged along a ring to reach every participant.
317 |br| `examples/s4u/app-token-ring/s4u-app-token-ring.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-token-ring/s4u-app-token-ring.cpp>`_
319 - **Master Workers:**
320 Another good old example, where one Master process has a bunch of task to dispatch to a set of several Worker
321 processes. This example comes in two equivalent variants, one
322 where the actors are specified as simple functions (which is easier to
323 understand for newcomers) and one where the actors are specified
324 as classes (which is more powerful for the users wanting to build
325 their own projects upon the example).
326 |br| `examples/s4u/app-masterworkers/s4u-app-masterworkers-class.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-masterworkers/s4u-app-masterworkers-class.cpp>`_
327 |br| `examples/s4u/app-masterworkers/s4u-app-masterworkers-fun.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-masterworkers/s4u-app-masterworkers-fun.cpp>`_
333 Classical protocol for Peer-to-Peer data diffusion.
334 |br| `examples/s4u/app-bittorrent/s4u-bittorrent.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-bittorrent/s4u-bittorrent.cpp>`_
337 Data broadcast over a ring of processes.
338 |br| `examples/s4u/app-chainsend/s4u-app-chainsend.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-chainsend/s4u-app-chainsend.cpp>`_
340 Distributed Hash Tables (DHT)
341 -----------------------------
344 One of the most famous DHT protocol.
345 |br| `examples/s4u/dht-chord/s4u-dht-chord.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/dht-chord/s4u-dht-chord.cpp>`_
347 .. TODO:: document here the examples about plugins
353 .. |cpp| image:: /img/lang_cpp.png
357 .. |py| image:: /img/lang_python.png