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 with
72 :cpp:func:`simgrid::s4u::this_actor::migrate()`.
73 |br| `examples/s4u/actor-migration/s4u-actor-migration.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-migration/s4u-actor-migration.cpp>`_
75 - **Waiting for the termination of an actor:** (joining on it)
76 :cpp:func:`simgrid::s4u::Actor::join()` allows to block the current
77 actor until the end of the receiving actor.
78 |br| `examples/s4u/actor-join/s4u-actor-join.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/actor-join/s4u-actor-join.cpp>`_
80 - **Yielding to other actors**.
81 The ```yield()``` function interrupts the execution of the current
82 actor, leaving a chance to the other actors that are ready to run
84 |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>`_
85 :cpp:func:`simgrid::s4u::this_actor::yield()`
86 |br| |py| `examples/python/actor-yield/actor-yield.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/actor-yield/actor-yield.py>`_
87 :py:func:`simgrid.this_actor.yield_()`
89 Traces Replay as a Workload
90 ---------------------------
92 This section details how to run trace-driven simulations. It is very
93 handy when you want to test an algorithm or protocol that only react
94 to external events. For example, many P2P protocols react to user
95 requests, but do nothing if there is no such event.
97 In such situations, you should write your protocol in C++, and separate
98 the workload that you want to play onto your protocol in a separate
99 text file. Declare a function handling each type of the events in your
100 trace, register them using :cpp:func:`xbt_replay_action_register()` in
101 your main, and then run the simulation.
103 Then, you can either have one trace file containing all your events,
104 or a file per simulated process: the former may be easier to work
105 with, but the second is more efficient on very large traces. Check
106 also the tesh files in the example directories for details.
108 - **Communication replay:**
109 Presents a set of event handlers reproducing classical communication
110 primitives (asynchronous send/receive at the moment).
111 |br| `examples/s4u/replay-comm/s4u-replay-comm.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/replay-comm/s4u-replay-comm.cpp>`_
114 Presents a set of event handlers reproducing classical I/O
115 primitives (open, read, close).
116 |br| `examples/s4u/replay-storage/s4u-replay-storage.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/replay-storage/s4u-replay-storage.cpp>`_
118 ==========================
119 Activities: what Actors do
120 ==========================
122 Communications on the Network
123 -----------------------------
125 - **Basic asynchronous communications:**
126 Illustrates how to have non-blocking communications, that are
127 communications running in the background leaving the process free
128 to do something else during their completion. The main functions
129 involved are :cpp:func:`simgrid::s4u::Mailbox::put_async()` and
130 :cpp:func:`simgrid::s4u::Comm::wait()`.
131 |br| `examples/s4u/async-wait/s4u-async-wait.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-wait/s4u-async-wait.cpp>`_
133 - **Waiting for all communications in a set:**
134 The :cpp:func:`simgrid::s4u::Comm::wait_all()` function is useful
135 when you want to block until all activities in a given set have
137 |br| `examples/s4u/async-waitall/s4u-async-waitall.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-waitall/s4u-async-waitall.cpp>`_
139 - **Waiting for the first completed communication in a set:**
140 The :cpp:func:`simgrid::s4u::Comm::wait_any()` function is useful
141 when you want to block until one activity of the set completes, no
142 matter which terminates first.
143 |br| `examples/s4u/async-waitany/s4u-async-waitany.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/async-waitany/s4u-async-waitany.cpp>`_
145 .. todo:: add the `ready` example here
147 .. _s4u_ex_execution:
149 Executions on the CPU
150 ---------------------
152 - **Basic execution:**
153 The computations done in your program are not reported to the
154 simulated world, unless you explicitely request the simulator to pause
155 the actor until a given amount of flops gets computed on its simulated
156 host. Some executions can be given an higher priority so that they
158 |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>`_
159 |br| |py| `examples/python/exec-basic/exec-basic.py <https://framagit.org/simgrid/simgrid/tree/master/examples/python/exec-basic/exec-basic.py>`_
161 - **Asynchronous execution:**
162 You can start asynchronous executions, just like you would fire
164 |br| `examples/s4u/exec-async/s4u-exec-async.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-async/s4u-exec-async.cpp>`_
166 - **Monitoring asynchronous executions:**
167 This example shows how to start an asynchronous execution, and
169 |br| `examples/s4u/exec-monitor/s4u-exec-monitor.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-monitor/s4u-exec-monitor.cpp>`_
171 - **Remote execution:**
172 Before its start, you can change the host on which a given execution will occur.
173 |br| `examples/s4u/exec-remote/s4u-exec-remote.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-remote/s4u-exec-remote.cpp>`_
175 - **Using Pstates on a host:**
176 Shows how define a set of pstatesfor a host in the XML, and how the current
177 pstate can be accessed/changed with :cpp:func:`simgrid::s4u::Host::get_pstate_speed` and :cpp:func:`simgrid::s4u::Host::set_pstate`.
178 |br| `examples/s4u/exec-dvfs/s4u-exec-dvfs.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-dvfs/s4u-exec-dvfs.cpp>`_
179 |br| `examples/platforms/energy_platform.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/energy_platform.xml>`_
181 - **Parallel executions:**
182 These objects are convenient abstractions of parallel
183 computational kernels that span over several machines, such as a
184 PDGEM and the other ScaLAPACK routines.
185 |br| `examples/s4u/exec-ptask/s4u-exec-ptask.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-ptask/s4u-exec-ptask.cpp>`_
187 I/O on Disks and Files
188 ----------------------
190 SimGrid provides two levels of abstraction to interact with the
191 simulated storages. At the simplest level, you simply create read and
192 write actions on the storage resources.
194 - **Access to raw storage devices:**
195 This example illustrates how to simply read and write data on a
196 simulated storage resource.
197 |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>`_
199 The FileSystem plugin provides a more detailed view, with the
200 classical operations over files: open, move, unlink, and of course
201 read and write. The file and disk sizes are also dealt with and can
202 result in short reads and short write, as in reality.
204 - **File Management:**
205 This example illustrates the use of operations on files
206 (read, write, seek, tell, unlink, etc).
207 |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>`_
210 I/O operations on files can also be done in a remote fashion,
211 i.e. when the accessed disk is not mounted on the caller's host.
212 |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>`_
214 Classical synchronization objects
215 ---------------------------------
218 Shows how to use simgrid::s4u::Mutex synchronization objects.
219 |br| `examples/s4u/synchro-mutex/s4u-synchro-mutex.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-mutex/s4u-synchro-mutex.cpp>`_
222 Shows how to use simgrid::s4u::Barrier synchronization objects.
223 |br| `examples/s4u/synchro-barrier/s4u-synchro-barrier.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-barrier/s4u-synchro-barrier.cpp>`_
226 Shows how to use simgrid::s4u::Semaphore synchronization objects.
227 |br| `examples/s4u/synchro-semaphore/s4u-synchro-semaphore.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/synchro-semaphore/s4u-synchro-semaphore.cpp>`_
229 =============================
230 Interacting with the Platform
231 =============================
233 - **Retrieving the list of hosts matching a given criteria:**
234 Shows how to filter the actors that match a given criteria.
235 |br| `examples/s4u/engine-filtering/s4u-engine-filtering.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/engine-filtering/s4u-engine-filtering.cpp>`_
237 - **User-defined properties:**
238 You can attach arbitrary information to most platform elements from
239 the XML file, and then interact with these values from your
240 program. Note that the changes are not written permanently on disk,
241 in the XML file nor anywhere else. They only last until the end of
244 - :cpp:func:`simgrid::s4u::Actor::get_property()` and :cpp:func:`simgrid::s4u::Actor::set_property()`
245 - :cpp:func:`simgrid::s4u::Host::get_property()` and :cpp:func:`simgrid::s4u::Host::set_property()`
246 - :cpp:func:`simgrid::s4u::Link::get_property()` and :cpp:func:`simgrid::s4u::Link::set_property()`
247 - :cpp:func:`simgrid::s4u::NetZone::get_property()` and :cpp:func:`simgrid::s4u::NetZone::set_property()`
249 |br| `examples/s4u/platform-properties/s4u-platform-properties.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/platform-properties/s4u-platform-properties.cpp>`_
250 |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>`_
251 |br| `examples/platforms/prop.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/prop.xml>`_
257 - **Describing the energy profiles in the platform:**
258 This platform file contains the energy profile of each links and
259 hosts, which is necessary to get energy consumption predictions.
260 As usual, you should not trust our example, and you should strive
261 to double-check that your instanciation matches your target platform.
262 |br| `examples/platforms/energy_platform.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/platforms/energy_platform.xml>`_
264 - **Consumption due to the CPU:**
265 This example shows how to retrieve the amount of energy consumed
266 by the CPU during computations, and the impact of the pstate.
267 |br| `examples/s4u/energy-exec/s4u-energy-exec.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-exec/s4u-energy-exec.cpp>`_
269 - **Consumption due to the network:**
270 This example shows how to retrieve and display the energy consumed
271 by the network during communications.
272 |br| `examples/s4u/energy-link/s4u-energy-link.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-link/s4u-energy-link.cpp>`_
274 - **Modeling the shutdown and boot of hosts:**
275 Simple example of model of model for the energy consumption during
276 the host boot and shutdown periods.
277 |br| `examples/s4u/energy-boot/platform_boot.xml <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-boot/platform_boot.xml>`_
278 |br| `examples/s4u/energy-boot/s4u-energy-boot.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/energy-boot/s4u-energy-boot.cpp>`_
280 =======================
281 Tracing and Visualizing
282 =======================
284 Tracing can be activated by various configuration options which
285 are illustrated in these example. See also the
286 :ref:`full list of options related to tracing <tracing_tracing_options>`.
288 It is interesting to run the process-create example with the following
289 options to see the task executions:
291 - **Platform Tracing:**
292 This program is a toy example just loading the platform, so that
293 you can play with the platform visualization. Recommanded options:
294 ``--cfg=tracing:yes --cfg=tracing/categorized:yes``
295 |br| `examples/s4u/trace-platform/s4u-trace-platform.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/trace-platform/s4u-trace-platform.cpp>`_
297 ========================
298 Larger SimGrid Examplars
299 ========================
301 This section contains application examples that are somewhat larger
302 than the previous examples.
305 This simple example just sends one message back and forth.
306 The tesh file laying in the directory show how to start the simulator binary, highlighting how to pass options to
307 the simulators (as detailed in Section :ref:`options`).
308 |br| `examples/s4u/app-pingpong/s4u-app-pingpong.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-pingpong/s4u-app-pingpong.cpp>`_
311 Shows how to implement a classical communication pattern, where a
312 token is exchanged along a ring to reach every participant.
313 |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>`_
315 - **Master Workers:**
316 Another good old example, where one Master process has a bunch of task to dispatch to a set of several Worker
317 processes. This example comes in two equivalent variants, one
318 where the actors are specified as simple functions (which is easier to
319 understand for newcomers) and one where the actors are specified
320 as classes (which is more powerful for the users wanting to build
321 their own projects upon the example).
322 |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>`_
323 |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>`_
329 Classical protocol for Peer-to-Peer data diffusion.
330 |br| `examples/s4u/app-bittorrent/s4u-bittorrent.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-bittorrent/s4u-bittorrent.cpp>`_
333 Data broadcast over a ring of processes.
334 |br| `examples/s4u/app-chainsend/s4u-app-chainsend.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/app-chainsend/s4u-app-chainsend.cpp>`_
336 Distributed Hash Tables (DHT)
337 -----------------------------
340 One of the most famous DHT protocol.
341 |br| `examples/s4u/dht-chord/s4u-dht-chord.cpp <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/dht-chord/s4u-dht-chord.cpp>`_
343 .. TODO:: document here the examples about plugins
349 .. |cpp| image:: /img/lang_cpp.png
353 .. |py| image:: /img/lang_python.png