1 /** \addtogroup MSG_API
3 MSG was the first distributed programming environment provided within SimGrid,
4 and is still the most commonly used nowadays. If you are unsure of the interface
5 you should use, they you probably want to use MSG. It constitutes a convenient
6 simplification of the reality of distributed systems. It can be used to build
7 rather realistic simulations, but remains simple to use: most unpleasant
8 technical elements can be abstracted away rather easily. If you want to use the
9 C programming language, your are in the right section. If you prefer not to use
10 this venerable but demanding language, please refer to the @ref MSG_Java, the
11 @ref MSG_LUA, or the @ref MSG_Ruby (that are distributed separately).
13 If you think that MSG may not be the interface you need, please consider the
14 other user interfaces provided by SimGrid: If you want to use DAGs, have a look
15 at the \ref SD_API programming environment. If you want to study an existing MPI
16 program, have a look at the \ref SMPI_API one. If none of those programming
17 environments fits your needs, you may consider implementing your own directly on
18 top of \ref SIMIX_API, or even on top of \ref SURF_API (but you want to contact
19 us before digging into these badly documented internal modules).
23 \section MSG_funct Offered functionalities
25 - \ref m_process_management
26 - \ref m_host_management
27 - \ref m_task_management
28 - \ref msg_mailbox_management
29 - \ref msg_file_management
33 - \ref msg_trace_driven
35 - \ref msg_deprecated_functions
38 Also make sure to visit the page @ref MSG_examples.
44 @defgroup msg_simulation Main MSG simulation Functions
46 @brief Describes how to setup and control your simulation.
48 The basic workflow is the following (check the \ref MSG_examples for
51 -# Initialize the library with #MSG_init
52 -# Create a platform (usually by parsing a file with
53 #MSG_create_environment)
54 -# Register the functions that your processes are supposed to run with
55 #MSG_function_register (and maybe #MSG_function_register_default)
56 -# Launch your processes from a deployment file with #MSG_launch_application
57 -# Run the simulation with #MSG_main
59 @htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Simulation Control" --> @endhtmlonly
62 /** @defgroup m_process_management Process Management Functions
64 * @brief This section describes the process structure of MSG
65 * (#msg_process_t) and the functions for managing it.
68 /** @defgroup m_host_management Host Management Functions
70 * @brief This section describes the host structure of MSG
73 /** @defgroup m_task_management Task Management Functions
75 * @brief This section describes the task structure of MSG
76 * (#msg_task_t) and the functions for managing it. See
77 * \ref msg_task_usage to see how to put the tasks in action.
79 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Tasks" --> \endhtmlonly
82 /** @defgroup msg_mailbox_management Mailbox Management Functions
84 * @brief This section describes the mailbox structure of MSG
85 * (#msg_mailbox_t) and the functions for managing it.
87 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Mailbox" --> \endhtmlonly
90 /** @defgroup msg_task_usage Task Actions
92 * @brief This section describes the functions that can be used
93 * by a process to execute, communicate or otherwise handle some task.
96 /** @defgroup msg_synchro Explicit Synchronization Functions
98 * @brief This section describes several explicit synchronization
99 * mechanisms existing in MSG: semaphores (#msg_sem_t) and friends.
101 * In some situations, these things are very helpful to synchronize processes without message exchanges.
104 /** @defgroup msg_VMs VMs
106 * @brief This section describes the interface created to mimic IaaS clouds.
108 * With it, you can create virtual machines to put your processes
109 * into, and interact directly with the VMs to manage groups of
112 * This interface is highly experimental at this point. Testing is
113 * welcomed, but do not expect too much of it right now. Even the
114 * interfaces may be changed in future releases of SimGrid (although
115 * things are expected to stabilize nicely before SimGrid v3.8).
116 * There is no guaranty on the rest of SimGrid, and there is less
117 * than that on this part.
121 /** @defgroup msg_storage_management Storage Management Functions
123 * @brief This section describes the storage structure of MSG
124 * (#msg_storage_t) and the functions for managing it. It
125 * is based on POSIX functions.
128 /** @defgroup msg_file_management File Management Functions
130 * @brief This section describes the file structure of MSG
131 * (#msg_file_t) and the functions for managing it. It
132 * is based on POSIX functions.
136 @defgroup msg_trace_driven Trace-driven simulations
138 @brief This section describes the functions allowing to build trace-driven simulations.
140 \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Trace-Driven" --> \endhtmlonly
142 This is very handy when you want to test an algorithm or protocol that
143 does nothing unless it receives some events from outside. For example,
144 a P2P protocol reacts to requests from the user, but does nothing if
145 there is no such event.
147 In such situations, SimGrid allows to write your protocol in your C
148 file, and the events to react to in a separate text file. Declare a
149 function handling each of the events that you want to accept in your
150 trace files, register them using #xbt_replay_action_register in your main,
151 and then use #MSG_action_trace_run to launch the simulation. You can
152 either have one trace file containing all your events, or a file per
155 Check the examples in <b>examples/msg/actions/actions.c</b> for details.
162 @defgroup MSG_LUA Lua bindings
164 @brief Lua bindings to MSG (\ref MSG_API)
166 @htmlonly <!-- DOXYGEN_NAVBAR_LABEL="LUA bindings" --> @endhtmlonly
168 This is the lua bindings of the \ref MSG_API interface.
170 \section lMSG_who Who should use this (and who shouldn't)
172 If you want to use MSG to study your algorithm, but you don't want to use the C
173 language (using \ref MSG_API), then you should use some bindings such as this
174 one. Just like the \ref MSG_Java, the advantage of the lua bindings is that they
175 are distributed directly with the main archive (in contrary to Ruby bindings,
176 that are distributed separately). Another advantage of lua is that there is
177 almost no performance loss with regard to the C version (at least there
178 shouldn't be any -- it is still to be precisely assessed).
180 \section MSG_Lua_funct Lua offered functionnalities in MSG
182 Almost all important features of the MSG interface are available from
183 the lua bindings. Unfortunately, since doxygen does not support the
184 lua modules implemented directly in C as we are using, there is no
185 ready to use reference documentation for this module. Even more than
186 for the other modules, you will have to dig into the source code of
187 the examples to learn how to use it.
189 \section Lua_examples Examples of lua MSG
191 - \ref MSG_ex_master_slave_lua
192 - \ref MSG_ex_master_slave_lua_bypass
193 - Also, the lua version of the Chord example (in the source tree)
194 is a working non-trivial example of use of the lua bindings
198 @defgroup MSG_examples MSG examples
200 @brief MSG examples from examples directory examples/msg
202 MSG comes with an extensive set of examples. It is sometimes difficult to find the one you need. This list aims at helping you finding the example from which you can learn what you want to.
204 \section msg_bsc_ex Basic examples
209 @defgroup msg_deprecated_functions MSG Deprecated
211 @brief This section describes the deprecated functions. PLEASE STOP USING THEM.
213 We don't remove them because the ability to run old scientific
214 code is something important to us. But these functionalities are
215 not actively supported anymore.
217 To access these functions, you should define the relevant option
218 at configuration time in ccmake.