};
/**
- * The task of the implementations of this class is to provide the
+ * A base class for algorithms that implement the task of coming up with
* communication patterns to retrieve data from other processes in a
- * dynamic-sparse way.
+ * dynamic-sparse way. In computer science, this is often called a
+ * <a href="https://en.wikipedia.org/wiki/Consensus_algorithm">consensus
+ * problem</a>.
*
* Dynamic-sparse means in this context:
- * - by the time this function is called, the other processes do
- * not know yet that they have to answer requests
- * - each process only has to communicate with a small subset of
- * processes of the MPI communicator
+ * - By the time this function is called, the other processes do
+ * not know yet that they have to answer requests.
+ * - Each process only has to communicate with a small subset of
+ * processes of the MPI communicator.
*
* Naturally, the user has to provide:
- * - a communicator
- * - for each rank a list of ranks of processes this process should
- * communicate to
- * - a functionality to pack/unpack data to be sent/received
+ * - A communicator.
+ * - For each rank a list of ranks of processes this process should
+ * communicate to.
+ * - Functionality to pack/unpack data to be sent/received.
*
- * The latter two features should be implemented in a class derived from
- * ConsensusAlgorithmProcess.
+ * This base class only introduces a basic interface to achieve
+ * these goals, while derived classes implement different algorithms
+ * to actually compute such communication patterns.
+ * The last two features of the list above this paragraph are implemented
+ * in classes derived from ConsensusAlgorithmProcess.
*
- * @tparam T1 the type of the elements of the vector to sent
- * @tparam T2 the type of the elements of the vector to received
+ * @tparam T1 The type of the elements of the vector to be sent.
+ * @tparam T2 The type of the elements of the vector to be received.
*
* @author Peter Munch, 2019
*/
const unsigned int n_procs;
};
+
/**
- * This class implements ConsensusAlgorithm, using only point-to-point
- * communications and a single IBarrier.
+ * This class implements a concrete algorithm for the ConsensusAlgorithm
+ * base class, using only point-to-point communications and a single
+ * IBarrier.
*
* @note This class closely follows the paper Hoefler, Siebert, Lumsdaine
* "Scalable Communication Protocols for Dynamic Sparse Data
* Isend/Irecv, where Irecv receives the answer to a request (with
* payload).
*
- * @tparam T1 the type of the elements of the vector to sent
- * @tparam T2 the type of the elements of the vector to received
+ * @tparam T1 The type of the elements of the vector to be sent.
+ * @tparam T2 The type of the elements of the vector to be received.
*
* @author Peter Munch, 2019
*/
};
/**
- * This class implements ConsensusAlgorithm, using a two step approach. In
+ * This class implements a concrete algorithm for the ConsensusAlgorithm
+ * base class, using a two step approach. In
* the first step the source ranks are determined and in the second step
* a static sparse data exchange is performed.
*
* when this process can stop waiting for requests, no IBarrier is
* needed.
*
- * @note The function compute_point_to_point_communication_pattern() is used
- * to determine the source processes, which implements a
- * PEX-algorithm from Hoefner et. al. "Scalable Communication
- * Protocols for Dynamic Sparse Data Exchange"
+ * @note The function
+ * Utilities::MPI::compute_point_to_point_communication_pattern() is
+ * used to determine the source processes, which implements a
+ * PEX-algorithm from Hoefner et al., "Scalable Communication
+ * Protocols for Dynamic Sparse Data Exchange".
*
- * @tparam T1 the type of the elements of the vector to sent
- * @tparam T2 the type of the elements of the vector to received
+ * @tparam T1 The type of the elements of the vector to be sent.
+ * @tparam T2 The type of the elements of the vector to be received.
*
* @author Peter Munch, 2019
*/
* A class which delegates its task to other ConsensusAlgorithm
* implementations depending on the number of processes in the
* MPI communicator. For a small number of processes it uses
- * ConsensusAlgorithm_PEX and for large number of processes
+ * ConsensusAlgorithm_PEX and for a large number of processes
* ConsensusAlgorithm_NBX. The threshold depends if the program is
* compiled in debug or release mode.
*
- * @tparam T1 the type of the elements of the vector to sent
- * @tparam T2 the type of the elements of the vector to received
+ * @tparam T1 The type of the elements of the vector to be sent.
+ * @tparam T2 The type of the elements of the vector to be received.
*
* @author Peter Munch, 2019
*/
* One might think: "But we know which rank a ghost DoF belongs to based on
* the subdomain id of the cell it is on". But this heuristic fails for DoFs
* on interfaces between ghost cells with different subdomain_ids, or
- * between a ghost cell and an artificial cell. Furthermore, this class
+ * between a ghost cell and an artificial cell. Furthermore, this function
* enables a completely abstract exchange of information without the help of
- * the grid in terms of neighbors.
+ * the mesh in terms of neighbors.
*
* The first argument passed to this function, @p owned_indices, must
* uniquely partition an index space between all processes.
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