3 The MSG Interface (legacy interface)
4 ####################################
8 MSG used to be the main API of SimGrid 3, but we are currently in
9 the process of releasing SimGrid 4. So MSG is frozen and will
10 probably never evolve. If you are starting a new project, you
11 should consider S4U instead. Note that the support for MSG will not
12 be removed from SimGrid before 2020Q4 or 2021Q1.
14 This interface is disabled by default. Pass -Denable_msg=ON to
15 cmake if you still need it.
17 MSG is a simple API to write algorithms organized with Concurrent
18 Sequential Processes (CSP) that interact by exchanging messages. It
19 constitutes a convenient simplification of the reality of distributed
20 systems. It can be used to build rather realistic simulations, but
21 remains simple to use: most unpleasant technical elements can be
22 abstracted away rather easily.
30 The basic workflow is the following:
32 - Initialize the library with :c:macro:`MSG_init`
33 - Create a platform (usually by parsing a file with :cpp:func:`MSG_create_environment`)
34 - Register the functions that your processes are supposed to run with
35 :cpp:func:`MSG_function_register` (and maybe :cpp:func:`MSG_function_register_default`)
36 - Launch your processes from a deployment file with :cpp:func:`MSG_launch_application`
37 - Run the simulation with :cpp:func:`MSG_main`
39 .. doxygenenum:: msg_error_t
41 .. doxygenfunction:: MSG_config
42 .. doxygenfunction:: MSG_create_environment
43 .. doxygenfunction:: MSG_function_register
44 .. doxygenfunction:: MSG_function_register_default
45 .. doxygenfunction:: MSG_get_clock
46 .. doxygenfunction:: MSG_get_sent_msg
47 .. doxygendefine:: MSG_init
48 .. doxygenfunction:: MSG_launch_application
49 .. doxygenfunction:: MSG_main
54 This describes the process structure :cpp:type:`msg_process_t` and the functions for managing it.
56 .. doxygentypedef:: msg_process_t
57 .. doxygenfunction:: MSG_process_attach
58 .. doxygenfunction:: MSG_process_auto_restart_set
59 .. doxygenfunction:: MSG_process_create
60 .. doxygenfunction:: MSG_process_create_with_arguments
61 .. doxygenfunction:: MSG_process_create_with_environment
62 .. doxygenfunction:: MSG_process_daemonize
63 .. doxygenfunction:: MSG_process_detach
64 .. doxygenfunction:: MSG_processes_as_dynar
65 .. doxygenfunction:: MSG_process_from_PID
66 .. doxygenfunction:: MSG_process_get_data
67 .. doxygenfunction:: MSG_process_get_host
68 .. doxygenfunction:: MSG_process_get_name
69 .. doxygenfunction:: MSG_process_get_number
70 .. doxygenfunction:: MSG_process_get_PID
71 .. doxygenfunction:: MSG_process_get_PPID
72 .. doxygenfunction:: MSG_process_get_properties
73 .. doxygenfunction:: MSG_process_get_property_value
74 .. doxygenfunction:: MSG_process_is_suspended
75 .. doxygenfunction:: MSG_process_join
76 .. doxygenfunction:: MSG_process_kill
77 .. doxygenfunction:: MSG_process_killall
78 .. doxygenfunction:: MSG_process_migrate
79 .. doxygenfunction:: MSG_process_on_exit
80 .. doxygenfunction:: MSG_process_ref
81 .. doxygenfunction:: MSG_process_restart
82 .. doxygenfunction:: MSG_process_resume
83 .. doxygenfunction:: MSG_process_self
84 .. doxygenfunction:: MSG_process_self_name
85 .. doxygenfunction:: MSG_process_self_PID
86 .. doxygenfunction:: MSG_process_self_PPID
87 .. doxygenfunction:: MSG_process_set_data
88 .. doxygenfunction:: MSG_process_set_data_cleanup
89 .. doxygenfunction:: MSG_process_set_kill_time
90 .. doxygenfunction:: MSG_process_sleep
91 .. doxygenfunction:: MSG_process_suspend
92 .. doxygenfunction:: MSG_process_unref
93 .. doxygenfunction:: MSG_process_yield
98 .. doxygentypedef:: msg_host_t
99 .. doxygenfunction:: MSG_host_by_name
100 .. doxygenfunction:: MSG_get_host_by_name
101 .. doxygenfunction:: MSG_get_host_number
102 .. doxygenfunction:: MSG_host_get_attached_storage_lists
103 .. doxygenfunction:: MSG_host_get_core_number
104 .. doxygenfunction:: MSG_host_get_data
105 .. doxygenfunction:: MSG_host_get_mounted_storage_list
106 .. doxygenfunction:: MSG_host_get_name
107 .. doxygenfunction:: MSG_host_get_nb_pstates
108 .. doxygenfunction:: MSG_host_get_load
109 .. doxygenfunction:: MSG_host_get_power_peak_at
110 .. doxygenfunction:: MSG_host_get_process_list
111 .. doxygenfunction:: MSG_host_get_properties
112 .. doxygenfunction:: MSG_host_get_property_value
113 .. doxygenfunction:: MSG_host_get_pstate
114 .. doxygenfunction:: MSG_host_get_speed
115 .. doxygenfunction:: MSG_host_is_on
116 .. doxygenfunction:: MSG_host_off
117 .. doxygenfunction:: MSG_host_on
118 .. doxygenfunction:: MSG_hosts_as_dynar
119 .. doxygenfunction:: MSG_host_self
120 .. doxygenfunction:: MSG_host_set_data
121 .. doxygenfunction:: MSG_host_set_property_value
122 .. doxygenfunction:: MSG_host_set_pstate
127 Task structure of MSG :cpp:type:`msg_task_t` and associated functions.
129 .. doxygentypedef:: msg_task_t
130 .. doxygendefine:: MSG_TASK_UNINITIALIZED
132 .. doxygenfunction:: MSG_parallel_task_create
133 .. doxygenfunction:: MSG_parallel_task_execute
134 .. doxygenfunction:: MSG_parallel_task_execute_with_timeout
135 .. doxygenfunction:: MSG_task_cancel
136 .. doxygenfunction:: MSG_task_create
137 .. doxygenfunction:: MSG_task_destroy
138 .. doxygenfunction:: MSG_task_dsend
139 .. doxygenfunction:: MSG_task_dsend_bounded
140 .. doxygenfunction:: MSG_task_execute
141 .. doxygenfunction:: MSG_task_get_bytes_amount
142 .. doxygenfunction:: MSG_task_get_category
143 .. doxygenfunction:: MSG_task_get_data
144 .. doxygenfunction:: MSG_task_get_flops_amount
145 .. doxygenfunction:: MSG_task_get_name
146 .. doxygenfunction:: MSG_task_get_remaining_communication
147 .. doxygenfunction:: MSG_task_get_remaining_work_ratio
148 .. doxygenfunction:: MSG_task_get_sender
149 .. doxygenfunction:: MSG_task_get_source
150 .. doxygenfunction:: MSG_task_irecv
151 .. doxygenfunction:: MSG_task_irecv_bounded
152 .. doxygenfunction:: MSG_task_isend
153 .. doxygenfunction:: MSG_task_isend_bounded
154 .. doxygenfunction:: MSG_task_listen
155 .. doxygenfunction:: MSG_task_listen_from
156 .. doxygenfunction:: MSG_task_receive
157 .. doxygenfunction:: MSG_task_receive_bounded
158 .. doxygenfunction:: MSG_task_receive_with_timeout
159 .. doxygenfunction:: MSG_task_receive_with_timeout_bounded
160 .. doxygendefine:: MSG_task_recv
161 .. doxygendefine:: MSG_task_recv_bounded
162 .. doxygenfunction:: MSG_task_send
163 .. doxygenfunction:: MSG_task_send_bounded
164 .. doxygenfunction:: MSG_task_send_with_timeout
165 .. doxygenfunction:: MSG_task_send_with_timeout_bounded
166 .. doxygenfunction:: MSG_task_set_bound
167 .. doxygenfunction:: MSG_task_set_bytes_amount
168 .. doxygenfunction:: MSG_task_set_category
169 .. doxygenfunction:: MSG_task_set_data
170 .. doxygenfunction:: MSG_task_set_flops_amount
171 .. doxygenfunction:: MSG_task_set_name
172 .. doxygenfunction:: MSG_task_set_priority
178 .. doxygenfunction:: MSG_mailbox_set_async
183 .. doxygentypedef:: msg_comm_t
185 .. doxygenfunction:: MSG_comm_destroy
186 .. doxygenfunction:: MSG_comm_get_status
187 .. doxygenfunction:: MSG_comm_get_task
188 .. doxygenfunction:: MSG_comm_test
189 .. doxygenfunction:: MSG_comm_testany
190 .. doxygenfunction:: MSG_comm_wait
191 .. doxygenfunction:: MSG_comm_waitall
192 .. doxygenfunction:: MSG_comm_waitany
194 Explicit Synchronization
195 ========================
197 Explicit synchronization mechanisms: semaphores (:cpp:type:`msg_sem_t`) and friends.
199 In some situations, these things are very helpful to synchronize processes without message exchanges.
204 .. doxygentypedef:: msg_bar_t
205 .. doxygenfunction:: MSG_barrier_destroy
206 .. doxygenfunction:: MSG_barrier_init
207 .. doxygenfunction:: MSG_barrier_wait
212 .. doxygentypedef:: msg_sem_t
213 .. doxygenfunction:: MSG_sem_acquire
214 .. doxygenfunction:: MSG_sem_acquire_timeout
215 .. doxygenfunction:: MSG_sem_destroy
216 .. doxygenfunction:: MSG_sem_get_capacity
217 .. doxygenfunction:: MSG_sem_init
218 .. doxygenfunction:: MSG_sem_release
219 .. doxygenfunction:: MSG_sem_would_block
224 This interface mimics IaaS clouds.
225 With it, you can create virtual machines to put your processes
226 into, and interact directly with the VMs to manage groups of
229 .. doxygentypedef:: msg_vm_t
230 .. doxygenfunction:: MSG_vm_create_core
231 .. doxygenfunction:: MSG_vm_create_multicore
232 .. doxygenfunction:: MSG_vm_destroy
233 .. doxygenfunction:: MSG_vm_get_name
234 .. doxygenfunction:: MSG_vm_get_pm
235 .. doxygenfunction:: MSG_vm_get_ramsize
236 .. doxygenfunction:: MSG_vm_is_created
237 .. doxygenfunction:: MSG_vm_is_running
238 .. doxygenfunction:: MSG_vm_is_suspended
239 .. doxygenfunction:: MSG_vm_resume
240 .. doxygenfunction:: MSG_vm_set_bound
241 .. doxygenfunction:: MSG_vm_set_ramsize
242 .. doxygenfunction:: MSG_vm_shutdown
243 .. doxygenfunction:: MSG_vm_start
244 .. doxygenfunction:: MSG_vm_suspend
248 Storage structure of MSG (:cpp:type:`msg_storage_t`) and associated functions, inspired from POSIX.
250 .. doxygentypedef:: msg_storage_t
251 .. doxygenfunction:: MSG_storage_get_by_name
252 .. doxygenfunction:: MSG_storage_get_data
253 .. doxygenfunction:: MSG_storage_get_host
254 .. doxygenfunction:: MSG_storage_get_name
255 .. doxygenfunction:: MSG_storage_get_properties
256 .. doxygenfunction:: MSG_storage_get_property_value
257 .. doxygenfunction:: MSG_storage_read
258 .. doxygenfunction:: MSG_storages_as_dynar
259 .. doxygenfunction:: MSG_storage_set_data
260 .. doxygenfunction:: MSG_storage_set_property_value
261 .. doxygenfunction:: MSG_storage_write
265 Network Zone (:cpp:class:`msg_file_t`) and associated functions.
267 .. doxygentypedef:: msg_netzone_t
268 .. doxygenfunction:: MSG_zone_get_by_name
269 .. doxygenfunction:: MSG_zone_get_hosts
270 .. doxygenfunction:: MSG_zone_get_name
271 .. doxygenfunction:: MSG_zone_get_property_value
272 .. doxygenfunction:: MSG_zone_get_root
273 .. doxygenfunction:: MSG_zone_get_sons
274 .. doxygenfunction:: MSG_zone_set_property_value
279 This section describes jMSG, the Java API to Simgrid. This API mimics
280 :ref:`MSG <MSG_doc>`, which is a simple yet somehow realistic interface.
281 The full reference documentation is provided at the end of this page.
283 Most of the documentation of the :ref:`MSG API <MSG_doc>` in C applies
284 directly to the Java bindings (any divergence is seen as a bug that we
285 should fix). MSG structures are mapped to Java objects as expected,
286 and the MSG functions are methods in these objects.
288 Installing the Java bindings
289 ============================
291 The easiest is to use a :ref:`precompiled jarfile <install_java_precompiled>`,
292 but some people may prefer to :ref:`compile it from the sources <install_src>`.
295 Using the Java bindings
296 =======================
298 In most cases, you can use the SimGrid bindings as if it was a Java
301 .. code-block:: shell
303 $ javac -classpath .:path/to/simgrid.jar your/java/Code.java
304 $ java -classpath .:path/to/simgrid.jar your.java.Code the/parameter/to/your/code
308 .. code-block:: shell
310 $ cd examples/deprecated/java
311 $ java -classpath ../../simgrid.jar:. .:../../simgrid.jar app.pingpong.Main ../platforms/platform.xml
313 Any SimGrid simulation (java or not) is usually constituted of several
314 kind of actors or processes (classes extending @c Msg.Process) that
315 are deployed over the hosts of the virtual platform. So, your code
316 should declare these actors, plus a Main class in charge of deploying
317 your actors on the platform. Please refer to the examples for details.
322 Actually, these bindings are not only implemented in Java. They do use
323 the C implementation of SimGrid. This should be transparent as this
324 library is directly included in the ``simgrid.jar`` file but things can
325 still go wrong is several ways.
327 Error: library simgrid not found
328 --------------------------------
330 This means that the JVM fails to load the native library. If you use a
331 precompiled jarfile, please report this bug.
333 If you built it yourself, you can try to use an installed version of
334 the library instead of the one included in the jar. For that, add the
335 path to the native library into the ``LD_LIBRARY_PATH`` variable (or in
336 the ``DYLD_LIBRARY_PATH`` on macOS).
338 pthread_create failed
339 ---------------------
341 You reached the amount of threads that can be run on your system. Try
342 increasing the thread limits of your operating system.
347 When using jMSG, your program can crash for 3 main reasons:
349 - Your Java part is not good: you'll have a good old java exception thrown,
350 and hence you should be able to correct it by yourself.
351 - Our java part is not good: you'll also have a java exception thrown, but
352 we have real doubts this can happen, since the java part is only a JNI
353 binding. The other option is that it crashed because you used incorrectly
354 the MSG API, so this means also you should have an MSGException. It means
355 you should read carefully MSG samples and/or documentation.
356 - Something has crashed in the C part. Okay, here comes the tricky
357 thing. It happens mainly for 2 reasons:
359 - When something goes wrong in your simulation, sometimes the C part stops
360 because you used SimGrid incorrectly, and JNI bindings are not fond of that.
361 It means that you'll have something that looks ugly, but you should be able
362 to identify what's going wrong in your code by carefully reading the whole
364 - It may happen that the problem comes directly from SimGrid: in this case,
365 the error should be uglier. In that case, you may submit a bug directly to
371 Package org.simgrid.msg
372 -----------------------
374 .. java:package:: org.simgrid.msg
379 Class org.simgrid.msg.As <java/org/simgrid/msg/As>
380 Class org.simgrid.msg.Comm <java/org/simgrid/msg/Comm>
381 Class org.simgrid.msg.File <java/org/simgrid/msg/File>
382 Class org.simgrid.msg.Host <java/org/simgrid/msg/Host>
383 Class org.simgrid.msg.HostFailureException <java/org/simgrid/msg/HostFailureException>
384 Class org.simgrid.msg.HostNotFoundException <java/org/simgrid/msg/HostNotFoundException>
385 Class org.simgrid.msg.JniException <java/org/simgrid/msg/JniException>
386 Class org.simgrid.msg.Msg <java/org/simgrid/msg/Msg>
387 Class org.simgrid.msg.MsgException <java/org/simgrid/msg/MsgException>
388 Class org.simgrid.msg.Mutex <java/org/simgrid/msg/Mutex>
389 Class org.simgrid.msg.Process <java/org/simgrid/msg/Process>
390 Class org.simgrid.msg.ProcessKilledError <java/org/simgrid/msg/ProcessKilledError>
391 Class org.simgrid.msg.ProcessNotFoundException <java/org/simgrid/msg/ProcessNotFoundException>
392 Class org.simgrid.msg.Semaphore <java/org/simgrid/msg/Semaphore>
393 Class org.simgrid.msg.Storage <java/org/simgrid/msg/Storage>
394 Class org.simgrid.msg.StorageNotFoundException <java/org/simgrid/msg/StorageNotFoundException>
395 Class org.simgrid.msg.Task <java/org/simgrid/msg/Task>
396 Class org.simgrid.msg.TaskCancelledException <java/org/simgrid/msg/TaskCancelledException>
397 Class org.simgrid.msg.TimeoutException <java/org/simgrid/msg/TimeoutException>
398 Class org.simgrid.msg.TransferFailureException <java/org/simgrid/msg/TransferFailureException>
399 Class org.simgrid.msg.VM <java/org/simgrid/msg/VM>