| .. Copyright (C) 2004-2009 The Trustees of Indiana University. |
| Use, modification and distribution is subject to the Boost Software |
| License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| http://www.boost.org/LICENSE_1_0.txt) |
| |
| ============================ |
| |Logo| MPI BSP Process Group |
| ============================ |
| |
| .. contents:: |
| |
| Introduction |
| ------------ |
| |
| The MPI ``mpi_process_group`` is an implementation of the `process |
| group`_ interface using the Message Passing Interface (MPI). It is the |
| primary process group used in the Parallel BGL at this time. |
| |
| Where Defined |
| ------------- |
| |
| Header ``<boost/graph/distributed/mpi_process_group.hpp>`` |
| |
| Reference |
| --------- |
| |
| :: |
| |
| namespace boost { namespace graph { namespace distributed { |
| |
| class mpi_process_group |
| { |
| public: |
| typedef boost::mpi::communicator communicator_type; |
| |
| // Process group constructors |
| mpi_process_group(communicator_type comm = communicator_type()); |
| mpi_process_group(std::size_t num_headers, std::size_t buffer_size, |
| communicator_type comm = communicator_type()); |
| |
| mpi_process_group(); |
| mpi_process_group(const mpi_process_group&, boost::parallel::attach_distributed_object); |
| |
| // Triggers |
| template<typename Type, typename Handler> |
| void trigger(int tag, const Handler& handler); |
| |
| template<typename Type, typename Handler> |
| void trigger_with_reply(int tag, const Handler& handler); |
| |
| trigger_receive_context trigger_context() const; |
| |
| // Helper operations |
| void poll(); |
| mpi_process_group base() const; |
| }; |
| |
| // Process query |
| int process_id(const mpi_process_group&); |
| int num_processes(const mpi_process_group&); |
| |
| // Message transmission |
| template<typename T> |
| void send(const mpi_process_group& pg, int dest, int tag, const T& value); |
| |
| template<typename T> |
| void receive(const mpi_process_group& pg, int source, int tag, T& value); |
| |
| optional<std::pair<int, int> > probe(const mpi_process_group& pg); |
| |
| // Synchronization |
| void synchronize(const mpi_process_group& pg); |
| |
| // Out-of-band communication |
| template<typename T> |
| void send_oob(const mpi_process_group& pg, int dest, int tag, const T& value); |
| |
| template<typename T, typename U> |
| void |
| send_oob_with_reply(const mpi_process_group& pg, int dest, int |
| tag, const T& send_value, U& receive_value); |
| |
| template<typename T> |
| void receive_oob(const mpi_process_group& pg, int source, int tag, T& value); |
| |
| } } } |
| |
| Since the ``mpi_process_group`` is an implementation of the `process |
| group`_ interface, we omit the description of most of the functions in |
| the prototype. Two constructors need special mentioning: |
| |
| :: |
| |
| mpi_process_group(communicator_type comm = communicator_type()); |
| |
| The constructor can take an optional MPI communicator. As default a communicator |
| constructed from MPI_COMM_WORLD is used. |
| |
| :: |
| |
| mpi_process_group(std::size_t num_headers, std::size_t buffer_size, |
| communicator_type comm = communicator_type()); |
| |
| |
| For performance fine tuning the maximum number of headers in a message batch |
| (num_headers) and the maximum combined size of batched messages (buffer_size) |
| can be specified. The maximum message size of a batch is |
| 16*num_headers+buffer_size. Sensible default values have been found by optimizing |
| a typical application on a cluster with Ethernet network, and are num_header=64k |
| and buffer_size=1MB, for a total maximum batches message size of 2MB. |
| |
| |
| |
| ----------------------------------------------------------------------------- |
| |
| Copyright (C) 2007 Douglas Gregor |
| |
| Copyright (C) 2007 Matthias Troyer |
| |
| .. |Logo| image:: pbgl-logo.png |
| :align: middle |
| :alt: Parallel BGL |
| :target: http://www.osl.iu.edu/research/pbgl |
| |
| .. _process group: process_group.html |