class for variable size scatter/gather buffer, root component More...

#include <mpisgvbuf.h>

Inheritance diagram for CMPIVarSGBufferRoot:

Collaboration diagram for CMPIVarSGBufferRoot:

Public Member Functions
	CMPIVarSGBufferRoot (MPI_Comm, int isize=16)

virtual	~CMPIVarSGBufferRoot ()

virtual void	clear ()

virtual void	gather ()

virtual void	scatter ()

virtual void	append (int, int)

virtual void	append (double, int)

virtual void	append (const char *, int)

virtual int	pop_int (int)

virtual double	pop_double (int)

virtual void	pop_doubles (int, double *, int)

Public Member Functions inherited from AMPISGBufferRoot
	AMPISGBufferRoot (MPI_Comm)

virtual	~AMPISGBufferRoot ()

virtual void	append (const Vec3 &, int)

virtual Vec3	pop_vector (int)

const MPI_Status &	status ()

Protected Member Functions
void	grow ()

void	growTo (int)

Private Attributes
char *	m_vbuffer

char *	m_dummy_vbuffer
	dummy buffer sent by root to itself More...

int	m_vbuffersize
	the size of the buffer per slice More...

int *	m_position
	the current end of the content in each slice More...

int *	m_rpos
	the number of bytes in the slice (i.e. m_position-m_displ) More...

int *	m_recvcount
	the buffer for the transfer of the size of the vbuffer More...

int *	m_displ

int	m_ndummy

Additional Inherited Members
Protected Attributes inherited from AMPISGBufferRoot
MPI_Comm	m_comm
	the MPI communicator used for the scatter/gather operations More...

int	m_rank
	the rank in this communicator More...

int	m_size
	size of the communicator More...

int	m_int_increment

int	m_dbl_increment
	the "packing size" of int/double More...

MPI_Status	m_status

Detailed Description

class for variable size scatter/gather buffer, root component

Author: Steffen Abe $Revision$ $Date$

Constructor & Destructor Documentation

◆ CMPIVarSGBufferRoot()

CMPIVarSGBufferRoot::CMPIVarSGBufferRoot	(	MPI_Comm	comm,
		int	isize = `16`
	)

Constructor for CMPISGBufferRoot

Parameters

comm	the MPI communicator
isize	initial buffer size per slice, default 16 byte

References m_displ, m_dummy_vbuffer, m_position, m_recvcount, m_rpos, AMPISGBufferRoot::m_size, m_vbuffer, and m_vbuffersize.

◆ ~CMPIVarSGBufferRoot()

CMPIVarSGBufferRoot::~CMPIVarSGBufferRoot ( )

virtual

References m_displ, m_dummy_vbuffer, m_position, m_recvcount, m_rpos, and m_vbuffer.

Member Function Documentation

◆ append() [1/3]

void CMPIVarSGBufferRoot::append	(	const char *	str,
		int	nslice
	)

virtual

Append a C-string to a given slice of the buffer.

Parameters

str	the string
nslice	the nr. of the slice

Warning: No check for overflow

Implements AMPISGBufferRoot.

References grow(), esys::lsm::bpu::len(), AMPISGBufferRoot::m_comm, m_displ, AMPISGBufferRoot::m_int_increment, m_position, AMPISGBufferRoot::m_size, m_vbuffer, and m_vbuffersize.

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◆ append() [2/3]

void CMPIVarSGBufferRoot::append	(	double	d,
		int	nslice
	)

virtual

Append a double to a given slice of the buffer.

Parameters

d	the double
nslice	the nr. of the slice

Warning: No check for overflow

Implements AMPISGBufferRoot.

References grow(), AMPISGBufferRoot::m_comm, AMPISGBufferRoot::m_dbl_increment, m_displ, m_position, AMPISGBufferRoot::m_size, m_vbuffer, and m_vbuffersize.

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◆ append() [3/3]

void CMPIVarSGBufferRoot::append	(	int	i,
		int	nslice
	)

virtual

Append an integer to a given slice of the buffer.

Parameters

i	the integer
nslice	the nr. of the slice

Warning: No check for overflow

Implements AMPISGBufferRoot.

References grow(), AMPISGBufferRoot::m_comm, m_displ, AMPISGBufferRoot::m_int_increment, m_position, AMPISGBufferRoot::m_size, m_vbuffer, and m_vbuffersize.

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◆ clear()

void CMPIVarSGBufferRoot::clear ( )

virtual

Implements AMPISGBufferRoot.

References m_displ, m_position, and AMPISGBufferRoot::m_size.

◆ gather()

void CMPIVarSGBufferRoot::gather ( )

virtual

Send data to the root process, using MPI_Gather and MPI_Gatherv. The receive buffer grows to fit the data if neccessary.

Implements AMPISGBufferRoot.

References growTo(), AMPISGBufferRoot::m_comm, m_displ, m_dummy_vbuffer, m_position, AMPISGBufferRoot::m_rank, m_recvcount, AMPISGBufferRoot::m_size, m_vbuffer, and m_vbuffersize.

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◆ grow()

void CMPIVarSGBufferRoot::grow ( )

protected

Grows the buffer to twice its current size, thus guaranteeing that append works in amortized constant time. Currently grows the buffer homogeneously, i.e. all slices have the same size.