X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/ad369fd510a511b07e8a515623f14440c3a416ba..599c5671721e2fd0b8f729f60d2852353f6bd5f3:/docs/source/app_s4u.rst diff --git a/docs/source/app_s4u.rst b/docs/source/app_s4u.rst index 1b255c71ce..2ada588dc5 100644 --- a/docs/source/app_s4u.rst +++ b/docs/source/app_s4u.rst @@ -1,8 +1,7 @@ .. _S4U_doc: -================= The S4U Interface -================= +################# .. raw:: html @@ -17,32 +16,39 @@ The S4U Interface
The S4U interface (SimGrid for you) mixes the full power of SimGrid -with the full power of C++. This is the prefered interface to describe -abstract algorithms in the domains of Cloud, P2P, HPC, IoT and similar +with the full power of C++. This is the preferred interface to describe +abstract algorithms in the domains of Cloud, P2P, HPC, IoT, and similar settings. -------------- +Currently (v3.21), S4U is definitely the way to go for long-term +projects. It is feature complete, but may still evolve slightly in the +future releases. It can already be used to do everything that can be +done in SimGrid, but you may have to adapt your code in future +releases. When this happens, compiling your code will produce +deprecation warnings for 4 releases (one year) before the removal of +the old symbols. +If you want an API that will never ever evolve in the future, you +should use the deprecated MSG API instead. + Main Concepts -------------- +************* A typical SimGrid simulation is composed of several |Actors|_, that execute user-provided functions. The actors have to explicitly use the -S4U interface to express their -:ref:`computation `, -:ref:`communication `, -:ref:`disk usage `, +S4U interface to express their :ref:`computation `, +:ref:`communication `, :ref:`disk usage `, and other |Activities|_, so that they get reflected within the simulator. These activities take place on resources such as |Hosts|_, |Links|_ and |Storages|_. SimGrid predicts the time taken by each -activity and orchestrates accordingly the actors waiting for the +activity and orchestrates the actors accordingly, waiting for the completion of these activities. When **communicating**, data is not directly sent to other actors but -posted onto a |Mailbox|_ that serve as rendez-vous point between +posted onto a |Mailbox|_ that serves as a rendez-vous point between communicating actors. This means that you don't need to know who you -are talking to, you just put your communication `Send` request in a -mailbox, and it will be matched with a complementary `Receive` +are talking to, you just put your communication `Put` request in a +mailbox, and it will be matched with a complementary `Get` request. Alternatively, actors can interact through **classical synchronization mechanisms** such as |Barrier|_, |Semaphore|_, |Mutex|_ and |ConditionVariable|_. @@ -52,48 +58,47 @@ itself in a |NetZone|_, that knows the networking path between one resource to another. Each NetZone is included in another one, forming a tree of NetZones which root zone contains the whole platform. -The :ref:`simgrid::s4u::this_actor -` namespace provides many helper -functions to simplify the code of actors. +The :ref:`simgrid::s4u::this_actor ` namespace +provides many helper functions to simplify the code of actors. - **Global Classes** - - :ref:`class s4u::Actor `: + - :ref:`class s4u::Actor `: Active entities executing your application. - - :ref:`class s4u::Engine ` + - :ref:`class s4u::Engine ` Simulation engine (singleton). - - :ref:`class s4u::Mailbox ` + - :ref:`class s4u::Mailbox ` Communication rendez-vous. - **Platform Elements** - - :ref:`class s4u::Host `: + - :ref:`class s4u::Host `: Actor location, providing computational power. - - :ref:`class s4u::Link ` + - :ref:`class s4u::Link ` Interconnecting hosts. - - :ref:`class s4u::NetZone `: - Sub-region of the platform, containing resources (Hosts, Link, etc). - - :ref:`class s4u::Storage ` + - :ref:`class s4u::NetZone `: + Sub-region of the platform, containing resources (Hosts, Links, etc). + - :ref:`class s4u::Storage ` Resource on which actors can write and read data. - - :ref:`class s4u::VirtualMachine `: + - :ref:`class s4u::VirtualMachine `: Execution containers that can be moved between Hosts. -- **Activities** (:ref:`class s4u::Activity `): +- **Activities** (:ref:`class s4u::Activity `): The things that actors can do on resources - - :ref:`class s4u::Comm ` + - :ref:`class s4u::Comm ` Communication activity, started on Mailboxes and consuming links. - - :ref:`class s4u::Exec ` + - :ref:`class s4u::Exec ` Computation activity, started on Host and consuming CPU resources. - - :ref:`class s4u::Io ` + - :ref:`class s4u::Io ` I/O activity, started on and consumming Storages. - **Synchronization Mechanisms**: Classical IPC that actors can use - - :ref:`class s4u::Barrier ` - - :ref:`class s4u::ConditionVariable ` - - :ref:`class s4u::Mutex ` - - :ref:`class s4u::Semaphore ` + - :ref:`class s4u::Barrier ` + - :ref:`class s4u::ConditionVariable ` + - :ref:`class s4u::Mutex ` + - :ref:`class s4u::Semaphore ` .. |Actors| replace:: **Actors** @@ -132,18 +137,20 @@ functions to simplify the code of actors. .. |Mutex| replace:: **Mutex** .. _Mutex: api/classsimgrid_1_1s4u_1_1Mutex.html ----------- +.. THE EXAMPLES + +.. include:: ../../examples/s4u/README.rst + Activities ----------- +********** -Activities represent the actions that consumes a resource, such as -:ref:`s4u::Comm ` that -consumes the *transmiting power* of :ref:`s4u::Link -` resources. +Activities represent the actions that consume a resource, such as a +:ref:`s4u::Comm ` that consumes the *transmiting power* of +:ref:`s4u::Link ` resources. -....................... +======================= Asynchronous Activities -....................... +======================= Every activity can be either **blocking** or **asynchronous**. For example, :cpp:func:`s4u::Mailbox::put() ` @@ -152,14 +159,14 @@ create blocking communications: the actor is blocked until the completion of that communication. Asynchronous communications do not block the actor during their execution but progress on their own. -Once your asynchronous activity is started, you can test for +Once your asynchronous activity is started, you can test for its completion using :cpp:func:`s4u::Activity::test() `. This function returns ``true`` if the activity completed already. You can also use :cpp:func:`s4u::Activity::wait() ` -to block until the completion of the activity. To wait at most for a given period, +to block until the completion of the activity. To wait for at most a given amount of time, use :cpp:func:`s4u::Activity::wait_for() `. Finally, to wait at most until a specified time limit, use -:cpp:func:`s4u::Activity::wait_for() `. +:cpp:func:`s4u::Activity::wait_until() `. .. todo:: @@ -167,13 +174,13 @@ Finally, to wait at most until a specified time limit, use Every kind of activities can be asynchronous: - - :ref:`s4u::CommPtr ` are created with + - :ref:`s4u::CommPtr ` are created with :cpp:func:`s4u::Mailbox::put_async() ` and :cpp:func:`s4u::Mailbox::get_async() `. - - :ref:`s4u::IoPtr ` are created with + - :ref:`s4u::IoPtr ` are created with :cpp:func:`s4u::Storage::read_async() ` and :cpp:func:`s4u::Storage::write_async() `. - - :ref:`s4u::ExecPtr ` are created with + - :ref:`s4u::ExecPtr ` are created with :cpp:func:`s4u::Host::exec_async() `. - In the future, it will become possible to have asynchronous IPC such as asynchronous mutex lock requests. @@ -189,7 +196,7 @@ vector of mailboxes. :end-before: init-end :dedent: 4 -You then start all communications that should occur concurrently with +Then, you start all the communications that should occur concurrently with :cpp:func:`s4u::Mailbox::put_async() `. Finally, the actor waits for the completion of all of them at once with @@ -197,13 +204,248 @@ with .. literalinclude:: ../../examples/s4u/async-waitall/s4u-async-waitall.cpp :language: c++ - :start-after: send-begin - :end-before: send-end + :start-after: put-begin + :end-before: put-end :dedent: 4 -..................... +===================== Activities Life cycle -..................... +===================== Sometimes, you want to change the setting of an activity before it even starts. + +.. todo:: write this section + +Memory Management +***************** + +For sake of simplicity, we use `RAII +`_ +everywhere in S4U. This is an idiom where resources are automatically +managed through the context. Provided that you never manipulate +objects of type Foo directly but always FooPtr references (which are +defined as `boost::intrusive_ptr +`_ +), you will never have to explicitely release the resource that +you use nor to free the memory of unused objects. + +Here is a little example: + +.. code-block:: cpp + + void myFunc() + { + simgrid::s4u::MutexPtr mutex = simgrid::s4u::Mutex::create(); // Too bad we cannot use `new` + + mutex->lock(); // use the mutex as a simple reference + // bla bla + mutex->unlock(); + + } // The mutex gets automatically freed because the only existing reference gets out of scope + +API Reference +************* + +.. _API_s4u_Activity: + +============= +s4u::Activity +============= + +.. doxygenclass:: simgrid::s4u::Activity + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Actor: + +========== +s4u::Actor +========== + +.. doxygentypedef:: ActorPtr + +.. doxygenclass:: simgrid::s4u::Actor + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Barrier: + +============ +s4u::Barrier +============ + +.. doxygentypedef:: BarrierPtr + +.. doxygenclass:: simgrid::s4u::Barrier + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Comm: + +========= +s4u::Comm +========= + +.. doxygentypedef:: CommPtr + +.. doxygenclass:: simgrid::s4u::Comm + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_ConditionVariable: + +====================== +s4u::ConditionVariable +====================== + +.. doxygentypedef:: ConditionVariablePtr + +.. doxygenclass:: simgrid::s4u::ConditionVariable + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Engine: + +=========== +s4u::Engine +=========== + +.. doxygenclass:: simgrid::s4u::Engine + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Exec: + +========= +s4u::Exec +========= + +.. doxygentypedef:: ExecPtr + +.. doxygenclass:: simgrid::s4u::Exec + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Host: + +========= +s4u::Host +========= + +.. doxygenclass:: simgrid::s4u::Host + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Io: + +======= +s4u::Io +======= + +.. doxygentypedef:: IoPtr + +.. doxygenclass:: simgrid::s4u::Io + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Link: + +========= +s4u::Link +========= + +.. doxygenclass:: simgrid::s4u::Link + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Mailbox: + +============ +s4u::Mailbox +============ + +.. doxygentypedef:: MailboxPtr + +.. doxygenclass:: simgrid::s4u::Mailbox + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Mutex: + +========== +s4u::Mutex +========== + +.. doxygentypedef:: MutexPtr + +.. doxygenclass:: simgrid::s4u::Mutex + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_NetZone: + +============ +s4u::NetZone +============ + +.. doxygenclass:: simgrid::s4u::NetZone + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Semaphore: + +============== +s4u::Semaphore +============== + +.. doxygentypedef:: SemaphorePtr + +.. doxygenclass:: simgrid::s4u::Semaphore + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_Storage: + +============ +s4u::Storage +============ + +.. doxygenclass:: simgrid::s4u::Storage + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_VirtualMachine: + +=================== +s4u::VirtualMachine +=================== + +.. doxygenclass:: simgrid::s4u::VirtualMachine + :members: + :protected-members: + :undoc-members: + +.. _API_s4u_this_actor: + +========================= +namespace s4u::this_actor +========================= + + +.. doxygennamespace:: simgrid::s4u::this_actor