commSchedule.H

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Class
    Foam::commSchedule

Description
    Determines the order in which a set of processors should communicate
    with one another.

    The communication order should
      - have maximum overlap
      - allow blocking communication without deadlock

    Does a very simple scheduling which assumes same time for all operations.

    After construction:
      - schedule() gives the order in which the input communication should occur
      - procSchedule()[proci] gives per proci

    Does not care whether 'talking' is first send, second receive or maybe
    full swap. This is all responsibility of caller.
    See Foam::rocessorTopology for use in scheduling processor boundary swaps.

SourceFiles
    commSchedule.C

\*---------------------------------------------------------------------------*/

#ifndef Foam_commSchedule_H
#define Foam_commSchedule_H

#include "labelPair.H"
#include "labelList.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{

/*---------------------------------------------------------------------------*\
                           Class commSchedule Declaration
\*---------------------------------------------------------------------------*/

class commSchedule
{
    // Private Data

        //- Order in which input communication has been scheduled
        labelList schedule_;

        //- Per processor the order in which communication has been scheduled
        labelListList procSchedule_;


public:

    //- Runtime type information
    ClassName("commSchedule");


    // Constructors

        //- Construct from wanted communication. Wanted communication is between
        //- two processors. Can be a one-way communication or
        //- two-way communication, that is up to the caller.
        //
        //  This class just
        //  determines an order for it such that any processor is only talking
        //  to one other at a time. After construction:
        //  - schedule is the order in which comms is done.
        //  - procSchedule[proci] is for proci the order in which comms is done.
        commSchedule(const label nProcs, const List<labelPair>& comms);


    // Member Functions

        //- Order in which comms is scheduled
        const labelList& schedule() const noexcept
        {
            return schedule_;
        }

        //- Per processor the order in which communication has been scheduled
        const labelListList& procSchedule() const noexcept
        {
            return procSchedule_;
        }
};


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace Foam

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#endif

// ************************************************************************* //