Wrapper for MPI communicator providing access to rank() and size() of the communicator. The Communicator is also access point to all MPI communications provided by KaMPIng. More...

#include <communicator.hpp>

Inheritance diagram for kamping::Communicator< DefaultContainerType, Plugins >:

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Collaboration diagram for kamping::Communicator< DefaultContainerType, Plugins >:

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Public Types
template<typename... Args>
using	default_container_type = DefaultContainerType<Args...>
	Type of the default container type to use for containers created inside operations of this communicator.

Public Member Functions
	Communicator ()
	Default constructor not specifying any MPI communicator and using `MPI_COMM_WORLD` by default.

	Communicator (MPI_Comm comm, bool take_ownership=false)
	Constructor where an MPI communicator has to be specified.

	Communicator (MPI_Comm comm, int root, bool take_ownership=false)
	Constructor where an MPI communicator and the default root have to be specified.

	Communicator (Communicator const &other)
	Copy constructor that duplicates the MPI_Comm and takes ownership of the newly created one in the copy.

	Communicator (Communicator &&other)
	Move constructor.

virtual	~Communicator ()
	Destructor that frees the contained `MPI_Comm` if it is owned by the Communicator.

Communicator &	operator= (Communicator &&other)
	Move assignment operator.

Communicator &	operator= (Communicator const &other)
	Copy assignment operator. Behaves according to the copy constructor.

void	swap (Communicator &other)
	Swaps the Communicator with another Communicator.

void	abort (int errorcode=1) const
	Terminates MPI execution environment (on all processes in this Communicator). Beware of MPI implementations who might terminate all processes, whether they are in this communicator or not.

int	rank_signed () const
	Rank of the current MPI process in the communicator as `int`.

size_t	rank () const
	Rank of the current MPI process in the communicator as `size_t`.

int	size_signed () const
	Number of MPI processes in this communicator as `int`.

size_t	size () const
	Number of MPI processes in this communicator as `size_t`.

size_t	num_numa_nodes () const
	Number of NUMA nodes (different shared memory regions) in this communicator. This operation is expensive (communicator splitting and communication). You should cache the result if you need it multiple times.

std::string	processor_name () const
	Get this 'processor's' name using `MPI_Get_processor_name`.

MPI_Comm	mpi_communicator () const
	MPI communicator corresponding to this communicator.

MPI_Comm	disown_mpi_communicator ()
	Disowns the wrapped MPI_Comm, i.e. it will not be freed in the destructor.

void	default_tag (int const default_tag)
	Set a new default tag used in point to point communication. The initial value is 0.

int	default_tag () const
	Default tag used in point to point communication. The initial value is 0.

void	root (int const new_root)
	Set a new root for MPI operations that require a root.

void	root (size_t const new_root)
	Set a new root for MPI operations that require a root.

size_t	root () const
	Default root for MPI operations that require a root as `size_t`.

int	root_signed () const
	Default root for MPI operations that require a root as `int`.

bool	is_root (int const root) const
	Check if this rank is the root rank.

bool	is_root (size_t const root) const
	Check if this rank is the root rank.

bool	is_root () const
	Check if this rank is the root rank.

Communicator	split (int const color, int const key=0) const
	Split the communicator in different colors.

Communicator	split_by_type (int const type) const
	Split the communicator by the specified type (e.g., shared memory)

Communicator	split_to_shared_memory () const
	Split the communicator into NUMA nodes.

Group	group () const
	Return the group associated with this communicator.

template<typename Ranks >
Communicator	create_subcommunicators (Ranks const &ranks_in_own_group) const
	Create subcommunicators.

Communicator	create_subcommunicators (RankRanges const &rank_ranges) const
	Create (sub-)communicators using a sparse representation for the ranks contained in the subcommunicators.

CommunicatorComparisonResult	compare (Communicator const &other_comm) const
	Compare this communicator with another given communicator. Uses `MPI_Comm_compare` internally.

int	convert_rank_to_communicator (int const rank, Communicator const &other_comm) const
	Convert a rank from this communicator to the rank in another communicator.

int	convert_rank_from_communicator (int const rank, Communicator const &other_comm) const
	Convert a rank from another communicator to the rank in this communicator.

size_t	rank_shifted_checked (int const distance) const
	Computes a rank that is `distance` ranks away from this MPI thread's current rank and checks if this is valid rank in this communicator.

size_t	rank_shifted_cyclic (int const distance) const
	Computes a rank that is some ranks apart from this MPI thread's rank modulo the communicator's size.

bool	is_valid_rank (int const rank) const
	Checks if a rank is a valid rank for this communicator, i.e., if the rank is in [0, size).

bool	is_valid_rank (size_t const rank) const
	Checks if a rank is a valid rank for this communicator, i.e., if the rank is in [0, size).

void	mpi_error_hook (int const error_code, std::string const &callee) const
	If `error_code != MPI_SUCCESS`, searchs the plugins for a public `mpi_error_handler(const int error_code, std::string& callee)` member. Searches the plugins front to back and calls the first handler found. If no handler is found, calls the default error hook. If error code is `MPI_SUCCESS`, does nothing.

void	mpi_error_default_handler (int const error_code, std::string const &function_name) const
	Default MPI error callback. Depending on `KASSERT_EXCEPTION_MODE` either throws a MpiErrorException if `error_code` != `MPI_SUCCESS` or fails an assertion.

template<typename... Args>
void	send (Args... args) const

template<typename... Args>
void	bsend (Args... args) const
	Convenience wrapper for MPI_Bsend. Calls kamping::Communicator::send() with the appropriate send mode set.

template<typename... Args>
void	ssend (Args... args) const
	Convenience wrapper for MPI_Ssend. Calls kamping::Communicator::send() with the appropriate send mode set.

template<typename... Args>
void	rsend (Args... args) const
	Convenience wrapper for MPI_Rsend. Calls kamping::Communicator::send() with the appropriate send mode set.

template<typename... Args>
auto	isend (Args... args) const

template<typename... Args>
auto	ibsend (Args... args) const
	Convenience wrapper for MPI_Ibsend. Calls kamping::Communicator::isend() with the appropriate send mode set.

template<typename... Args>
auto	issend (Args... args) const
	Convenience wrapper for MPI_Issend. Calls kamping::Communicator::isend() with the appropriate send mode set.

template<typename... Args>
auto	irsend (Args... args) const
	Convenience wrapper for MPI_Irsend. Calls kamping::Communicator::isend() with the appropriate send mode set.

template<typename... Args>
auto	probe (Args... args) const

template<typename... Args>
auto	iprobe (Args... args) const

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	recv (Args... args) const

template<typename recv_value_type_tparam , typename... Args>
auto	recv_single (Args... args) const
	Convience wrapper for receiving single values via `MPI_Recv`.

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	try_recv (Args... args) const

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	irecv (Args... args) const

template<typename... Args>
auto	alltoall (Args... args) const
	Wrapper for `MPI_Alltoall`.

template<typename... Args>
auto	alltoall_inplace (Args... args) const
	Wrapper for the in-place version of Communicator::alltoall.

template<typename... Args>
auto	alltoallv (Args... args) const
	Wrapper for `MPI_Alltoallv`.

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	scatter (Args... args) const

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	scatter_single (Args... args) const

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	scatterv (Args... args) const
	Wrapper for `MPI_Scatterv`.

template<typename... Args>
auto	reduce (Args... args) const

template<typename... Args>
auto	reduce_single (Args... args) const
	Wrapper for `MPI_Reduce`.

template<typename... Args>
auto	scan (Args... args) const

template<typename... Args>
auto	scan_inplace (Args... args) const
	Wrapper for the in-place version of Communicator::scan().

template<typename... Args>
auto	scan_single (Args... args) const
	Wrapper for `MPI_Scan` for single elements.

template<typename... Args>
auto	exscan (Args... args) const
	Wrapper for `MPI_Exscan`.

template<typename... Args>
auto	exscan_inplace (Args... args) const
	Wrapper for the in-place version of Communicator::exscan().

template<typename... Args>
auto	exscan_single (Args... args) const
	Wrapper for `MPI_exscan` for single elements.

template<typename... Args>
auto	allreduce (Args... args) const
	Wrapper for `MPI_Allreduce`; which is semantically a reduction followed by a broadcast.

template<typename... Args>
auto	allreduce_inplace (Args... args) const
	Wrapper for the in-place version of Communicator::allreduce().

template<typename... Args>
auto	allreduce_single (Args... args) const
	Wrapper for `MPI_Allreduce`; which is semantically a reduction followed by a broadcast.

template<typename... Args>
auto	iallreduce (Args... args) const
	Wrapper for `MPI_Iallreduce`.

template<typename... Args>
auto	gather (Args... args) const
	Wrapper for `MPI_Gather`.

template<typename... Args>
auto	gatherv (Args... args) const
	Wrapper for `MPI_Gatherv`.

template<typename... Args>
auto	allgather (Args... args) const
	Wrapper for `MPI_Allgather`.

template<typename... Args>
auto	allgather_inplace (Args... args) const
	Wrapper for the in-place version of `MPI_Allgather`.

template<typename... Args>
auto	allgatherv (Args... args) const
	Wrapper for `MPI_Allgatherv`.

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	bcast (Args... args) const
	Wrapper for `MPI_Bcast`.

template<typename recv_value_type_tparam = kamping::internal::unused_tparam, typename... Args>
auto	bcast_single (Args... args) const
	Wrapper for `MPI_Bcast`.

template<typename... Args>
void	barrier (Args... args) const
	Perform a `MPI_Barrier` on this communicator.

template<typename... Args>
auto	ibarrier (Args... args) const
	Perform a non-blocking barrier synchronization on this communicator using `MPI_Ibarrier`. The call is associated with a kamping::Request (either allocated by KaMPIng or provided by the user). Only when the request has completed, it is guaranteed that all ranks have reached the barrier.

template<typename Value >
bool	is_same_on_all_ranks (Value const &value) const
	Checks if all ranks provide the same value to this collective.

Protected Attributes
size_t	_rank
	Rank of the MPI process in this communicator.

size_t	_size
	Number of MPI processes in this communicator.

MPI_Comm	_comm
	Corresponding MPI communicator.

size_t	_root
	Default root for MPI operations that require a root.

int	_default_tag
	Default tag value used in point to point communication.

bool	_owns_mpi_comm

Detailed Description

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>
class kamping::Communicator< DefaultContainerType, Plugins >

Wrapper for MPI communicator providing access to rank() and size() of the communicator. The Communicator is also access point to all MPI communications provided by KaMPIng.

Template Parameters

DefaultContainerType	The default container type to use for containers created by KaMPIng. Defaults to std::vector.
Plugins	Plugins adding functionality to KaMPIng. Plugins should be classes taking a `Communicator` template parameter and can assume that they are castable to `Communicator` from which they can call any function of `kamping::Communicator`. See `test/plugin_tests.cpp` for examples.

Member Typedef Documentation

◆ default_container_type

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

template<typename... Args>

using kamping::Communicator< DefaultContainerType, Plugins >::default_container_type = DefaultContainerType<Args...>

Type of the default container type to use for containers created inside operations of this communicator.

Template Parameters

Args	Arguments to the container type.

Constructor & Destructor Documentation

◆ Communicator() [1/4]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

kamping::Communicator< DefaultContainerType, Plugins >::Communicator	(	MPI_Comm	comm,
		bool	take_ownership = false )

inlineexplicit

Constructor where an MPI communicator has to be specified.

Parameters

comm	MPI communicator that is wrapped by this `Communicator`.
take_ownership	Whether the Communicator should take ownership of comm, i.e. free it in the destructor.

◆ Communicator() [2/4]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

kamping::Communicator< DefaultContainerType, Plugins >::Communicator	(	MPI_Comm	comm,
		int	root,
		bool	take_ownership = false )

inlineexplicit

Constructor where an MPI communicator and the default root have to be specified.

Parameters

comm	MPI communicator that is wrapped by this `Communicator`.
root	Default root that is used by MPI operations requiring a root.
take_ownership	Whether the Communicator should take ownership of comm, i.e. free it in the destructor.

◆ Communicator() [3/4]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

kamping::Communicator< DefaultContainerType, Plugins >::Communicator ( Communicator< DefaultContainerType, Plugins > const & other )

inline

Copy constructor that duplicates the MPI_Comm and takes ownership of the newly created one in the copy.

Parameters

other The Communicator to copy.

◆ Communicator() [4/4]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

kamping::Communicator< DefaultContainerType, Plugins >::Communicator ( Communicator< DefaultContainerType, Plugins > && other )

inline

Move constructor.

Parameters

other The Communicator to move.

Member Function Documentation

◆ abort()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

void kamping::Communicator< DefaultContainerType, Plugins >::abort ( int errorcode = 1 ) const

inline

Terminates MPI execution environment (on all processes in this Communicator). Beware of MPI implementations who might terminate all processes, whether they are in this communicator or not.

Parameters

errorcode Error code to return to invoking environment.

◆ compare()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

CommunicatorComparisonResult kamping::Communicator< DefaultContainerType, Plugins >::compare ( Communicator< DefaultContainerType, Plugins > const & other_comm ) const

inline

Compare this communicator with another given communicator. Uses MPI_Comm_compare internally.

Parameters

other_comm Communicator with which this communicator is compared.

Returns: Return whether compared communicators are identical, congruent, similar or unequal.

◆ convert_rank_from_communicator()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

int kamping::Communicator< DefaultContainerType, Plugins >::convert_rank_from_communicator	(	int const	rank,
		Communicator< DefaultContainerType, Plugins > const &	other_comm ) const

inline

Convert a rank from another communicator to the rank in this communicator.

Parameters

rank	The rank in other_comm
other_comm	The communicator to convert the rank from

Returns: The rank in this communicator

◆ convert_rank_to_communicator()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

int kamping::Communicator< DefaultContainerType, Plugins >::convert_rank_to_communicator	(	int const	rank,
		Communicator< DefaultContainerType, Plugins > const &	other_comm ) const

inline

Convert a rank from this communicator to the rank in another communicator.

Parameters

rank	The rank in this communicator
other_comm	The communicator to convert the rank to

Returns: The rank in other_comm

◆ create_subcommunicators() [1/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator kamping::Communicator< DefaultContainerType, Plugins >::create_subcommunicators ( RankRanges const & rank_ranges ) const

inline

Create (sub-)communicators using a sparse representation for the ranks contained in the subcommunicators.

This split method requires globally available information on the ranks in the split communicators. A rank r must know all other ranks which will be part of the subcommunicator to which r will belong. This information can be used by the MPI implementation to execute a communicator split more efficiently. The method must be called by all ranks in the communicator.

Parameters

rank_ranges Contains the ranks that will be part of this rank's new (sub-)communicator in a sparse representation via rank ranges each consisting of (first rank, last rank and stride). All ranks specified in ranks_in_own_group must have an identical ranks_in_own_group argument. Furthermore, this set must not be empty.

Returns: Communicator wrapping the newly split MPI communicator.

◆ create_subcommunicators() [2/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

template<typename Ranks >

Communicator kamping::Communicator< DefaultContainerType, Plugins >::create_subcommunicators ( Ranks const & ranks_in_own_group ) const

inline

Create subcommunicators.

This method requires globally available information on the ranks in the subcommunicators. A rank r must know all other ranks which will be part of the subcommunicator to which r will belong. This information can be used by the MPI implementation to execute a communicator split more efficiently. The method must be called by all ranks in the communicator.

Template Parameters

Ranks Contiguous container storing integers.

Parameters

ranks_in_own_group Contains the ranks that will be part of this rank's new (sub-)communicator. All ranks specified in ranks_in_own_group must have an identical ranks_in_own_group argument. Furthermore, this set must not be empty.

Returns: Communicator wrapping the newly split MPI communicator.

◆ disown_mpi_communicator()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

MPI_Comm kamping::Communicator< DefaultContainerType, Plugins >::disown_mpi_communicator ( )

inline

Disowns the wrapped MPI_Comm, i.e. it will not be freed in the destructor.

Returns: MPI communicator corresponding to this communicator.

◆ group()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Group kamping::Communicator< DefaultContainerType, Plugins >::group ( ) const

inline

Return the group associated with this communicator.

Returns: The group associated with this communicator.

◆ is_root() [1/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::is_root ( ) const

inline

Check if this rank is the root rank.

Returns: Return true if this rank is the root rank.

◆ is_root() [2/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::is_root ( int const root ) const

inline

Check if this rank is the root rank.

Returns: Return true if this rank is the root rank.

Parameters

root	The custom root's rank.

◆ is_root() [3/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::is_root ( size_t const root ) const

inline

Check if this rank is the root rank.

Returns: Return true if this rank is the root rank.

Parameters

root	The custom root's rank.

◆ is_same_on_all_ranks()

template<template< typename... > typename DefaultContainerType, template< typename, template< typename... > typename > typename... Plugins>

template<typename Value >

bool kamping::Communicator< DefaultContainerType, Plugins >::is_same_on_all_ranks ( Value const & value ) const

Checks if all ranks provide the same value to this collective.

This collective function checks if all ranks have called it with the same value. The result is returned on all ranks.

Template Parameters

Value Type of the value to check. Must be comparable with operator==.

Parameters

value The value of this rank. This value is compared with the ones provided by all other ranks.

Returns: true if all ranks have provided the same value, false otherwise.

◆ is_valid_rank() [1/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::is_valid_rank ( int const rank ) const

inline

Checks if a rank is a valid rank for this communicator, i.e., if the rank is in [0, size).

Returns: true if rank in [0,size) and false otherwise.

◆ is_valid_rank() [2/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::is_valid_rank ( size_t const rank ) const

inline

Checks if a rank is a valid rank for this communicator, i.e., if the rank is in [0, size).

Returns: true if rank in [0,size) and false otherwise.

◆ mpi_communicator()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

MPI_Comm kamping::Communicator< DefaultContainerType, Plugins >::mpi_communicator ( ) const

inline

MPI communicator corresponding to this communicator.

Returns: MPI communicator corresponding to this communicator.

◆ num_numa_nodes()

template<template< typename... > typename DefaultContainerType, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::num_numa_nodes ( ) const

Number of NUMA nodes (different shared memory regions) in this communicator. This operation is expensive (communicator splitting and communication). You should cache the result if you need it multiple times.

Returns: Number of compute nodes (hostnames) in this communicator.

◆ operator=() [1/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator & kamping::Communicator< DefaultContainerType, Plugins >::operator= ( Communicator< DefaultContainerType, Plugins > && other )

inline

Move assignment operator.

Parameters

other The Communicator to move.

◆ operator=() [2/2]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator & kamping::Communicator< DefaultContainerType, Plugins >::operator= ( Communicator< DefaultContainerType, Plugins > const & other )

inline

Copy assignment operator. Behaves according to the copy constructor.

Parameters

other The Communicator to copy.

◆ processor_name()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

std::string kamping::Communicator< DefaultContainerType, Plugins >::processor_name ( ) const

inline

Get this 'processor's' name using MPI_Get_processor_name.

Returns: This 'processor's' name. Nowadays, this oftentimes is the hostname.

◆ rank()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::rank ( ) const

inline

Rank of the current MPI process in the communicator as size_t.

Returns: Rank of the current MPI process in the communicator as size_t.

◆ rank_shifted_checked()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::rank_shifted_checked ( int const distance ) const

inline

Computes a rank that is distance ranks away from this MPI thread's current rank and checks if this is valid rank in this communicator.

The resulting rank is valid, iff it is at least zero and less than this communicator's size. The distance can be negative. Unlike rank_shifted_cyclic(), this does not guarantee a valid rank but can indicate if the resulting rank is not valid.

Parameters

distance Amount current rank is decreased or increased by.

Returns: Rank if rank is in [0, size of communicator) and ASSERT/EXCEPTION? otherwise.

◆ rank_shifted_cyclic()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::rank_shifted_cyclic ( int const distance ) const

inline

Computes a rank that is some ranks apart from this MPI thread's rank modulo the communicator's size.

When we need to compute a rank that is greater (or smaller) than this communicator's rank, we can use this function. It computes the rank that is distance ranks appart. However, this function always returns a valid rank, as it computes the rank in a circular fashion, i.e., $new\_rank=(rank + distance) \% size$ .

Parameters

distance Distance of the new rank to the rank of this MPI thread.

Returns: The circular rank that is distance ranks apart from this MPI threads rank.

◆ rank_signed()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

int kamping::Communicator< DefaultContainerType, Plugins >::rank_signed ( ) const

inline

Rank of the current MPI process in the communicator as int.

Returns: Rank of the current MPI process in the communicator as int.

◆ root() [1/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::root ( ) const

inline

Default root for MPI operations that require a root as size_t.

Returns: Default root for MPI operations that require a root as size_t.

◆ root() [2/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

void kamping::Communicator< DefaultContainerType, Plugins >::root ( int const new_root )

inline

Set a new root for MPI operations that require a root.

Parameters

new_root The new default root.

◆ root() [3/3]

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

void kamping::Communicator< DefaultContainerType, Plugins >::root ( size_t const new_root )

inline

Set a new root for MPI operations that require a root.

Parameters

new_root The new default root.

◆ root_signed()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

int kamping::Communicator< DefaultContainerType, Plugins >::root_signed ( ) const

inline

Default root for MPI operations that require a root as int.

Returns: Default root for MPI operations that require a root as int.

◆ size()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

size_t kamping::Communicator< DefaultContainerType, Plugins >::size ( ) const

inline

Number of MPI processes in this communicator as size_t.

Returns: Number of MPI processes in this communicator as size_t.

◆ size_signed()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

int kamping::Communicator< DefaultContainerType, Plugins >::size_signed ( ) const

inline

Number of MPI processes in this communicator as int.

Returns: Number of MPI processes in this communicator int.

◆ split()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator kamping::Communicator< DefaultContainerType, Plugins >::split	(	int const	color,
		int const	key = 0 ) const

inline

Split the communicator in different colors.

Parameters

color	All ranks that have the same color will be in the same new communicator.
key	By default, ranks in the new communicator are determined by the underlying MPI library (if `key` is 0). Otherwise, ranks are ordered the same way the keys are ordered.

Returns: Communicator wrapping the newly split MPI communicator.

◆ split_by_type()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator kamping::Communicator< DefaultContainerType, Plugins >::split_by_type ( int const type ) const

inline

Split the communicator by the specified type (e.g., shared memory)

Parameters

type	The only standard-conform value is `MPI_COMM_TYPE_SHARED` but your MPI implementation might support other types. For example: `OMPI_COMM_TYPE_L3CACHE`.

◆ split_to_shared_memory()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

Communicator kamping::Communicator< DefaultContainerType, Plugins >::split_to_shared_memory ( ) const

inline

Split the communicator into NUMA nodes.

Returns: Communicator wrapping the newly split MPI communicator. Each rank will be in the communicator corresponding to its NUMA node.

◆ swap()

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

void kamping::Communicator< DefaultContainerType, Plugins >::swap ( Communicator< DefaultContainerType, Plugins > & other )

inline

Swaps the Communicator with another Communicator.

Parameters

other The Communicator to swap with.

Member Data Documentation

◆ _owns_mpi_comm

template<template< typename... > typename DefaultContainerType = std::vector, template< typename, template< typename... > typename > typename... Plugins>

bool kamping::Communicator< DefaultContainerType, Plugins >::_owns_mpi_comm

protected

Whether the Communicator Objects owns the contained MPI_Comm, i.e. whether it is allowed to free it in the destructor.

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

include/kamping/communicator.hpp
include/kamping/collectives/allgather.hpp
include/kamping/collectives/allreduce.hpp
include/kamping/collectives/alltoall.hpp
include/kamping/collectives/barrier.hpp
include/kamping/collectives/bcast.hpp
include/kamping/collectives/exscan.hpp
include/kamping/collectives/gather.hpp
include/kamping/collectives/iallreduce.hpp
include/kamping/collectives/ibarrier.hpp
include/kamping/collectives/reduce.hpp
include/kamping/collectives/scan.hpp
include/kamping/collectives/scatter.hpp
include/kamping/comm_helper/is_same_on_all_ranks.hpp
include/kamping/comm_helper/num_numa_nodes.hpp
include/kamping/p2p/iprobe.hpp
include/kamping/p2p/irecv.hpp
include/kamping/p2p/isend.hpp
include/kamping/p2p/probe.hpp
include/kamping/p2p/recv.hpp
include/kamping/p2p/send.hpp
include/kamping/p2p/try_recv.hpp

Public Types

Public Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ default_container_type

Constructor & Destructor Documentation

◆ Communicator() [1/4]

◆ Communicator() [2/4]

◆ Communicator() [3/4]

◆ Communicator() [4/4]

Member Function Documentation

◆ abort()

◆ compare()

◆ convert_rank_from_communicator()

◆ convert_rank_to_communicator()

◆ create_subcommunicators() [1/2]

◆ create_subcommunicators() [2/2]

◆ disown_mpi_communicator()

◆ group()

◆ is_root() [1/3]

◆ is_root() [2/3]

◆ is_root() [3/3]

◆ is_same_on_all_ranks()

◆ is_valid_rank() [1/2]

◆ is_valid_rank() [2/2]

◆ mpi_communicator()

◆ num_numa_nodes()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ processor_name()

◆ rank()

◆ rank_shifted_checked()

◆ rank_shifted_cyclic()

◆ rank_signed()

◆ root() [1/3]

◆ root() [2/3]

◆ root() [3/3]

◆ root_signed()

◆ size()

◆ size_signed()

◆ split()

◆ split_by_type()

◆ split_to_shared_memory()

◆ swap()

Member Data Documentation

◆ _owns_mpi_comm