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Class TempLat::ParafaftMemoryLayout

template <size_t NDim>

ClassList > TempLat > ParafaftMemoryLayout

Memory layout computation for parafaft. More...

  • #include <parafaftmemorylayout.h>

Inherits the following classes: TempLat::ParafaftPlanner

Public Functions

Type Name
ParafaftMemoryLayout ()
virtual FFTLayoutStruct< NDim > computeLocalSizes (MPICartesianGroup group, device::IdxArray< NDim > nGridPoints, bool forbidTransposition=false) override
Compute local memory sizes for this MPI rank.

Public Functions inherited from TempLat::ParafaftPlanner

See TempLat::ParafaftPlanner

Type Name
ParafaftPlanner ()
virtual std::shared_ptr< FFTPlanInterface< double, NDim > > getPlans_double (const MPICartesianGroup & group, const FFTLayoutStruct< NDim > & layout) override
Create double-precision plans.
virtual std::shared_ptr< FFTPlanInterface< float, NDim > > getPlans_float (const MPICartesianGroup & group, const FFTLayoutStruct< NDim > & layout) override
Create float-precision plans.
virtual void setPlannerPatience (int level) override
Set planner patience level.

Public Functions inherited from TempLat::FFTLibraryInterface

See TempLat::FFTLibraryInterface

Type Name
FFTLibraryInterface () = default
virtual FFTLayoutStruct< NDim > computeLocalSizes (MPICartesianGroup group, device::IdxArray< NDim > nGridPoints, bool forbidTransposition=false) = 0
given an actual setup, return the description of the subarray of the global problem that this process holds.
virtual IntrinsicScales getIntrinsicRescaleToGetUnnormalizedFFT (device::Idx nGridPoints) = 0
The lattice objects expect an unnormalized FFT, such as the one FFTW gives: applying once forward and then backward should return the input values multiplied by nGridPoints^nDimensions, i.e. the total number of values in the problem. If your library does not respect that, return the factor by which we must multiply the output values to obtain the unnormalized FFT. Return defaultIntrinsicScales (exact (double) 1) in order not to waste time, if your library does it like FFTW.
virtual device::Idx getMaximumNumberOfDimensionsToDivide (device::Idx nDimensions) = 0
Return the number of dimensions over which the MPI processes can be distributed, given a problem of dimension nDimensions. FFTW can only divide in 1 dimension: the leading dimension. ParaFaFT can divide an N dimensional setup over the leading N - 1 dimensions.
virtual std::shared_ptr< FFTPlanInterface< double, NDim > > getPlans_double (const MPICartesianGroup & group, const FFTLayoutStruct< NDim > & layout) = 0
Create fully working plans, which must self-destruct in the FFTPlanInterface 's destructor. Use shared_ptr's.
virtual std::shared_ptr< FFTPlanInterface< float, NDim > > getPlans_float (const MPICartesianGroup & group, const FFTLayoutStruct< NDim > & layout) = 0
Create fully working plans, which must self-destruct in the FFTPlanInterface 's destructor. Use shared_ptr's. Since we use virtual methods here, we cannot use templates. Only one type of dynamic typing allowed by C++, either runtime (virtual) or compile time (template).
virtual void setPlannerPatience (int level) = 0
If your library has different levels of patience for the planning phase, set it here.
virtual ~FFTLibraryInterface () = default

Detailed Description

Parafaft uses a (D-1)-dimensional pencil decomposition. For 3D: * Real space: distributed in dimensions [0,1], full in dimension [2] * Complex space: full in dimension [0], distributed in dimensions [1,2]

Note: We use the FFTW flag for FFTLayoutStruct compatibility since parafaft uses FFTW conventions for r2c padding.

Unit test: ctest -R test-parafaftmemorylayout

Public Functions Documentation

function ParafaftMemoryLayout

inline TempLat::ParafaftMemoryLayout::ParafaftMemoryLayout () 

function computeLocalSizes

Compute local memory sizes for this MPI rank.

inline virtual FFTLayoutStruct < NDim > TempLat::ParafaftMemoryLayout::computeLocalSizes (
    MPICartesianGroup group,
    device::IdxArray< NDim > nGridPoints,
    bool forbidTransposition=false
) override

Creates a temporary parafaft object to query local sizes, then populates FFTLayoutStruct with the configuration and Fourier space layouts.

Implements TempLat::FFTLibraryInterface::computeLocalSizes



The documentation for this class was generated from the following file cosmolatticeweb/tmp/code_source/templat/include/TempLat/fft/external/parafaft/parafaftmemorylayout.h