Class that stores marshalled data for ghost communications. More...

#include <particle_packing.hpp>

Public Member Functions
char *	data ()
	Returns a pointer to the non-bond storage.

const char *	data () const

std::size_t	size () const
	Returns the number of elements in the non-bond storage.

void	resize (std::size_t new_size)
	Resizes the underlying storage s.t.

auto &	bonds ()
	Returns a reference to the bond storage.

const auto &	bonds () const

auto	make_span ()

Detailed Description

Class that stores marshalled data for ghost communications.

To store and retrieve data, use the adapter classes below.

Invariant: every byte in the non-bond buffer is written by the caller (pack_cells / MPI irecv) before it is read (unpack_cells / add_forces). The buffer therefore uses a default-init allocator so that resize()-on-grow does not zero-fill bytes that will be immediately overwritten, eliminating the __memset_avx2 overhead visible in perf profiles at large particle counts. The bond buffer is kept as a plain std::vector<char> because it is serialized via boost.mpi (which requires exact byte semantics) and is on the cold resort-only path.

Definition at line 91 of file particle_packing.hpp.

Member Function Documentation

◆ bonds() [1/2]

auto & GhostComm::CommBuf::bonds ( )

inline

Returns a reference to the bond storage.

Definition at line 110 of file particle_packing.hpp.

Referenced by GhostComm::pack_cells(), GhostComm::anonymous_namespace{HaloExchange.cpp}::run_collective(), and GhostComm::unpack_cells().

◆ bonds() [2/2]

const auto & GhostComm::CommBuf::bonds ( ) const

inline

Definition at line 111 of file particle_packing.hpp.

◆ data() [1/2]

char * GhostComm::CommBuf::data ( )

inline

Returns a pointer to the non-bond storage.

Definition at line 96 of file particle_packing.hpp.

◆ data() [2/2]

const char * GhostComm::CommBuf::data ( ) const

inline

Definition at line 97 of file particle_packing.hpp.

◆ make_span()

auto GhostComm::CommBuf::make_span ( )

inline

Definition at line 113 of file particle_packing.hpp.

Referenced by GhostComm::add_dip_fld(), GhostComm::add_forces(), GhostComm::add_rattle(), GhostComm::local_cell_copy(), GhostComm::pack_cells(), and GhostComm::unpack_cells().

◆ resize()

void GhostComm::CommBuf::resize ( std::size_t new_size )

inline

Resizes the underlying storage s.t.

the object is capable of holding new_size chars. Bytes added by growth are left uninitialized; the caller must write them (pack_cells / MPI irecv) before reading.

Definition at line 107 of file particle_packing.hpp.

Referenced by GhostComm::local_cell_copy(), GhostComm::pack_cells(), and GhostComm::anonymous_namespace{HaloExchange.cpp}::run_collective().