Cabana::Scatter< HaloType, SliceType > Class Template Reference

Synchronously scatter data from the ghosts to the local decomposition of a slice using the halo reverse communication plan. This is a multiply-owned to uniquely owned communication. More...

#include <Cabana_Halo.hpp>

Inheritance diagram for Cabana::Scatter< HaloType, SliceType >:

Collaboration diagram for Cabana::Scatter< HaloType, SliceType >:

Public Types
using	commspace_type = typename HaloType::commspace_type
	Communication space type.
using	base_type
	Base type.
using	plan_type = typename base_type::plan_type
	Communication plan type (Halo).
using	execution_space = typename base_type::execution_space
	Kokkos execution space.
using	memory_space = typename base_type::memory_space
	Kokkos memory space.
using	data_type = typename base_type::data_type
	Communication data type.
using	buffer_type = typename base_type::buffer_type
	Communication buffer type.

Public Member Functions
	Scatter (HaloType halo, SliceType slice, const double overallocation=1.0)
auto	totalSend ()
	Total scatter send size for this rank.
auto	totalReceive ()
	Total scatter receive size for this rank.
auto	totalSend (const HaloType &halo)
	Total gather send size for this rank.
auto	totalReceive (const HaloType &halo)
	Total gather receive size for this rank.
void	apply () override
	Perform the scatter operation.
template<class ExecutionSpace, class CommSpaceType>
std::enable_if_t< std::is_same< CommSpaceType, Mpi >::value, void >	applyImpl (ExecutionSpace, CommSpaceType)
	Vanilla Mpi implementation of the scatter operation.
void	reserve (const HaloType &halo, const SliceType &slice, const double overallocation)
	Reserve new buffers as needed and update the halo and slice data. Reallocation only occurs if there is not enough space in the buffers.
void	reserve (const HaloType &halo, const SliceType &slice)
	Reserve new buffers as needed and update the halo and slice data.

Detailed Description

template<class HaloType, class SliceType>
class Cabana::Scatter< HaloType, SliceType >

Synchronously scatter data from the ghosts to the local decomposition of a slice using the halo reverse communication plan. This is a multiply-owned to uniquely owned communication.

In a scatter operation results from ghosted values on other processors are scattered back to the owning processor of the ghost and the value associated with the ghost is summed into the locally owned value the ghost represents. If a locally owned element is ghosted on multiple ranks, then multiple contributions will be made to the sum, one for each rank.

Member Typedef Documentation

base_type

template<class HaloType, class SliceType>

using Cabana::Scatter< HaloType, SliceType >::base_type

Initial value:

 
        CommunicationData<HaloType, CommunicationDataSlice<SliceType>>

Base type.

Constructor & Destructor Documentation

Scatter()

template<class HaloType, class SliceType>

Cabana::Scatter< HaloType, SliceType >::Scatter ( HaloType halo, SliceType slice, const double overallocation = 1.0 )

inline

Parameters

halo	The Halo to be used for the gather.
slice	The slice on which to perform the gather. The slice should have a size equivalent to halo.numGhost() + halo.numLocal(). The locally owned elements are expected to appear first (i.e. in the first halo.numLocal() elements) and the ghosted elements are expected to appear second (i.e. in the next halo.numGhost() elements()).
overallocation	An optional factor to keep extra space in the buffers to avoid frequent resizing.

Member Function Documentation

reserve() [1/2]

template<class HaloType, class SliceType>

void Cabana::Scatter< HaloType, SliceType >::reserve ( const HaloType & halo, const SliceType & slice )

inline

Reserve new buffers as needed and update the halo and slice data.

Parameters

halo	The Halo to be used for the scatter.
slice	The slice on which to perform the scatter.

reserve() [2/2]

template<class HaloType, class SliceType>

void Cabana::Scatter< HaloType, SliceType >::reserve ( const HaloType & halo, const SliceType & slice, const double overallocation )

inline

Reserve new buffers as needed and update the halo and slice data. Reallocation only occurs if there is not enough space in the buffers.

Parameters

halo	The Halo to be used for the scatter.
slice	The slice on which to perform the scatter.
overallocation	An optional factor to keep extra space in the buffers to avoid frequent resizing.

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The documentation for this class was generated from the following file:

• core/src/Cabana_Halo.hpp