SAMRAI::tbox::SAMRAI_MPI Struct Reference

Provides C++ wrapper around MPI routines. More...

#include <source/toolbox/parallel/SAMRAI_MPI.h>

List of all members.

Public Types
typedef int	comm
typedef int	group
typedef int	request
typedef int	status
Static Public Member Functions
static void	setCallAbortInSerialInsteadOfExit (bool flag=true)
static void	abort ()
static void	init (int *argc, char **argv[])
static void	finalize ()
static void	initialize ()
static void	setCommunicator (SAMRAI_MPI::comm communicator)
static SAMRAI_MPI::comm	getCommunicator ()
static int	getRank ()
static int	getNodes ()
static void	updateOutgoingStatistics (const int messages, const int bytes)
static void	updateIncomingStatistics (const int messages, const int bytes)
static int	getOutgoingMessages ()
static int	getOutgoingBytes ()
static int	getIncomingMessages ()
static int	getIncomingBytes ()
static int	getTreeDepth ()
static void	barrier ()
static double	sumReduction (const double x)
static void	sumReduction (double *x, const int n=1)
static float	sumReduction (const float x)
static void	sumReduction (float *x, const int n=1)
static dcomplex	sumReduction (const dcomplex x)
static void	sumReduction (dcomplex *x, const int n=1)
static int	sumReduction (const int x)
static void	sumReduction (int *x, const int n=1)
static double	minReduction (const double x, int *rank_of_min=NULL)
static void	minReduction (double *x, const int n=1, int *rank_of_min=NULL)
static float	minReduction (const float x, int *rank_of_min=NULL)
static void	minReduction (float *x, const int n=1, int *rank_of_min=NULL)
static int	minReduction (const int x, int *rank_of_min=NULL)
static void	minReduction (int *x, const int n=1, int *rank_of_min=NULL)
static double	maxReduction (const double x, int *rank_of_max=NULL)
static void	maxReduction (double *x, const int n=1, int *rank_of_max=NULL)
static float	maxReduction (const float x, int *rank_of_max=NULL)
static void	maxReduction (float *x, const int n=1, int *rank_of_max=NULL)
static int	maxReduction (const int x, int *rank_of_max=NULL)
static void	maxReduction (int *x, const int n=1, int *rank_of_max=NULL)
static void	allToOneSumReduction (int *x, const int n, const int root=0)
static int	bcast (const int x, const int root)
static void	bcast (int *x, int &length, const int root)
static void	bcast (char *x, int &length, const int root)
static void	send (const int *buf, const int length, const int receiving_proc_number, const bool send_length=true, int tag=-1)
	This function sends an MPI message with an integer array to another processer.
static void	sendBytes (const void *buf, const int number_bytes, const int receiving_proc_number)
	This function sends an MPI message with an array of bytes (MPI_BYTES) to receiving_proc_number.
static int	recvBytes (void *buf, int number_bytes)
	This function receives an MPI message with an array of max size number_bytes (MPI_BYTES) from any processer.
static void	recv (int *buf, int &length, const int sending_proc_number, const bool get_length=true, int tag=-1)
	This function receives an MPI message with an integer array from another processer.
static void	allGather (const int *x_in, int size_in, int *x_out, int size_out)
static void	allGather (const double *x_in, int size_in, double *x_out, int size_out)
static void	allGather (int x_in, int *x_out)
static void	allGather (double x_in, double *x_out)
Static Public Attributes
static comm	commWorld
static comm	commNull

---

Detailed Description

Provides C++ wrapper around MPI routines.

Class SAMRAI_MPI groups common MPI routines into one globally-accessible location. It provides small, simple routines that are common in MPI code. In some cases, the calling syntax has been simplified for convenience. Moreover, there is no reason to include the preprocessor ifdef/endif guards around these calls, since the MPI libraries are not called in these routines if the MPI libraries are not being used (e.g., when writing serial code).

Note that this class is a utility class to group function calls in one name space (all calls are to static functions). Thus, you should never attempt to instantiate a class of type MPI; simply call the functions as static functions using the MPI::function(...) syntax.

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Member Typedef Documentation

typedef int SAMRAI::tbox::SAMRAI_MPI::comm

MPI Types

typedef int SAMRAI::tbox::SAMRAI_MPI::group

typedef int SAMRAI::tbox::SAMRAI_MPI::request

typedef int SAMRAI::tbox::SAMRAI_MPI::status

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Member Function Documentation

void SAMRAI::tbox::SAMRAI_MPI::setCallAbortInSerialInsteadOfExit

(

bool

flag = true

)

[static]

Set boolean flag indicating whether exit or abort is called when running with one processor. Calling this function influences the behavior of calls to SAMRAI_MPI::abort(). By default, the flag is true meaning that abort() will be called. Passing false means exit(-1) will be called.

void SAMRAI::tbox::SAMRAI_MPI::abort

(

)

[static]

Call MPI_Abort or exit depending on whether running with one or more processes and value set by function above, if called. The default is to call exit(-1) if running with one processor and to call MPI_Abort() otherwise. This function avoids having to guard abort calls in application code.

void SAMRAI::tbox::SAMRAI_MPI::init	(	int *	argc,
		char **	argv[]
	)			[inline, static]

Call MPI_Init. Use of this function avoids guarding MPI init calls in application code.

void SAMRAI::tbox::SAMRAI_MPI::finalize

(

)

[inline, static]

Call MPI_Finalize. Use of this function avoids guarding MPI finalize calls in application code.

void SAMRAI::tbox::SAMRAI_MPI::initialize

(

)

[static]

Initialize the MPI utility class. The MPI utility class must be initialized after the call to MPI_Init or SAMRAI_MPI::init.

void SAMRAI::tbox::SAMRAI_MPI::setCommunicator

(

SAMRAI_MPI::comm

communicator

)

[inline, static]

Set the communicator that is used for the MPI communication routines. The default communicator is MPI_COMM_WORLD.

SAMRAI_MPI::comm SAMRAI::tbox::SAMRAI_MPI::getCommunicator

(

)

[inline, static]

Get the current MPI communicator. The default communicator is MPI_COMM_WORLD.

int SAMRAI::tbox::SAMRAI_MPI::getRank

(

)

[inline, static]

Return the processor rank (identifier) from 0 through the number of processors minus one.

int SAMRAI::tbox::SAMRAI_MPI::getNodes

(

)

[inline, static]

Return the number of processors (nodes).

void SAMRAI::tbox::SAMRAI_MPI::updateOutgoingStatistics	(	const int	messages,
		const int	bytes
	)			[inline, static]

Update the statistics for outgoing messages. Statistics are automatically updated for the reduction calls in MPI.

void SAMRAI::tbox::SAMRAI_MPI::updateIncomingStatistics	(	const int	messages,
		const int	bytes
	)			[inline, static]

Update the statistics for incoming messages. Statistics are automatically updated for the reduction calls in MPI.

int SAMRAI::tbox::SAMRAI_MPI::getOutgoingMessages

(

)

[inline, static]

Return the number of outgoing messages.

int SAMRAI::tbox::SAMRAI_MPI::getOutgoingBytes

(

)

[inline, static]

Return the number of outgoing message bytes.

int SAMRAI::tbox::SAMRAI_MPI::getIncomingMessages

(

)

[inline, static]

Return the number of incoming messages.

int SAMRAI::tbox::SAMRAI_MPI::getIncomingBytes

(

)

[inline, static]

Return the number of incoming message bytes.

int SAMRAI::tbox::SAMRAI_MPI::getTreeDepth

(

)

[static]

Get the depth of the reduction trees given the current number of MPI processors.

void SAMRAI::tbox::SAMRAI_MPI::barrier

(

)

[static]

Perform a global barrier across all processors.

double SAMRAI::tbox::SAMRAI_MPI::sumReduction

(

const double

x

)

[static]

Perform a scalar sum reduction on a double across all nodes. Each processor contributes a value x of type double, and the sum is returned from the function.

void SAMRAI::tbox::SAMRAI_MPI::sumReduction	(	double *	x,
		const int	n = 1
	)			[static]

Perform an array sum reduction on doubles across all nodes. Each processor contributes an array of values of type double, and the element-wise sum is returned in the same array.

float SAMRAI::tbox::SAMRAI_MPI::sumReduction

(

const float

x

)

[static]

Perform a scalar sum reduction on a float across all nodes. Each processor contributes a value x of type float, and the sum is returned from the function.

void SAMRAI::tbox::SAMRAI_MPI::sumReduction	(	float *	x,
		const int	n = 1
	)			[static]

Perform an array sum reduction on floats across all nodes. Each processor contributes an array of values of type float, and the element-wise sum is returned in the same array.

dcomplex SAMRAI::tbox::SAMRAI_MPI::sumReduction

(

const dcomplex

x

)

[static]

Perform a scalar sum reduction on a dcomplex across all nodes. Each processor contributes a value x of type dcomplex, and the sum is returned from the function.

void SAMRAI::tbox::SAMRAI_MPI::sumReduction	(	dcomplex *	x,
		const int	n = 1
	)			[static]

Perform an array sum reduction on dcomplexes across all nodes. Each processor contributes an array of values of type dcomplex, and the element-wise sum is returned in the same array.

int SAMRAI::tbox::SAMRAI_MPI::sumReduction

(

const int

x

)

[static]

Perform a scalar sum reduction on an integer across all nodes. Each processor contributes a value x of type int, and the sum is returned from the function.

void SAMRAI::tbox::SAMRAI_MPI::sumReduction	(	int *	x,
		const int	n = 1
	)			[static]

Perform an array sum reduction on integers across all nodes. Each processor contributes an array of values of type int, and the element-wise sum is returned in the same array.

double SAMRAI::tbox::SAMRAI_MPI::minReduction	(	const double	x,
		int *	rank_of_min = NULL
	)			[static]

Perform a scalar min reduction on a double across all nodes. Each processor contributes a value x of type double, and the minimum is returned from the function.

If a 'rank_of_min' argument is provided, it will set it to the rank of process holding the minimum value.

void SAMRAI::tbox::SAMRAI_MPI::minReduction	(	double *	x,
		const int	n = 1,
		int *	rank_of_min = NULL
	)			[static]

Perform an array min reduction on doubles across all nodes. Each processor contributes an array of values of type double, and the element-wise minimum is returned in the same array.

If a 'rank_of_min' argument is provided, it will set the array to the rank of process holding the minimum value. Like the double argument, the size of the supplied 'rank_of_min' array should be n.

float SAMRAI::tbox::SAMRAI_MPI::minReduction	(	const float	x,
		int *	rank_of_min = NULL
	)			[static]

Perform a scalar min reduction on a float across all nodes. Each processor contributes a value x of type float, and the minimum is returned from the function.

If a 'rank_of_min' argument is provided, it will set it to the rank of process holding the minimum value.

void SAMRAI::tbox::SAMRAI_MPI::minReduction	(	float *	x,
		const int	n = 1,
		int *	rank_of_min = NULL
	)			[static]

Perform an array min reduction on floats across all nodes. Each processor contributes an array of values of type float, and the element-wise minimum is returned in the same array.

If a 'rank_of_min' argument is provided, it will set the array to the rank of process holding the minimum value. Like the double argument, the size of the supplied 'rank_of_min' array should be n.

int SAMRAI::tbox::SAMRAI_MPI::minReduction	(	const int	x,
		int *	rank_of_min = NULL
	)			[static]

Perform a scalar min reduction on an integer across all nodes. Each processor contributes a value x of type int, and the minimum is returned from the function.

If a 'rank_of_min' argument is provided, it will set it to the rank of process holding the minimum value.

void SAMRAI::tbox::SAMRAI_MPI::minReduction	(	int *	x,
		const int	n = 1,
		int *	rank_of_min = NULL
	)			[static]

Perform an array min reduction on integers across all nodes. Each processor contributes an array of values of type int, and the element-wise minimum is returned in the same array.

If a 'rank_of_min' argument is provided, it will set the array to the rank of process holding the minimum value. Like the double argument, the size of the supplied 'rank_of_min' array should be n.

double SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	const double	x,
		int *	rank_of_max = NULL
	)			[static]

Perform a scalar max reduction on a double across all nodes. Each processor contributes a value x of type double, and the maximum is returned from the function.

If a 'rank_of_max' argument is provided, it will set it to the rank of process holding the maximum value.

void SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	double *	x,
		const int	n = 1,
		int *	rank_of_max = NULL
	)			[static]

Perform an array max reduction on doubles across all nodes. Each processor contributes an array of values of type double, and the element-wise maximum is returned in the same array.

If a 'rank_of_max' argument is provided, it will set the array to the rank of process holding the maximum value. Like the double argument, the size of the supplied 'rank_of_max' array should be n.

float SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	const float	x,
		int *	rank_of_max = NULL
	)			[static]

Perform a scalar max reduction on a float across all nodes. Each processor contributes a value x of type float, and the maximum is returned from the function.

If a 'rank_of_max' argument is provided, it will set it to the rank of process holding the maximum value.

void SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	float *	x,
		const int	n = 1,
		int *	rank_of_max = NULL
	)			[static]

Perform an array max reduction on floats across all nodes. Each processor contributes an array of values of type float, and the element-wise maximum is returned in the same array.

If a 'rank_of_max' argument is provided, it will set the array to the rank of process holding the maximum value. Like the double argument, the size of the supplied 'rank_of_max' array should be n.

int SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	const int	x,
		int *	rank_of_max = NULL
	)			[static]

Perform a scalar max reduction on an integer across all nodes. Each processor contributes a value x of type int, and the maximum is returned from the function.

If a 'rank_of_max' argument is provided, it will set it to the rank of process holding the maximum value.

void SAMRAI::tbox::SAMRAI_MPI::maxReduction	(	int *	x,
		const int	n = 1,
		int *	rank_of_max = NULL
	)			[static]

Perform an array max reduction on integers across all nodes. Each processor contributes an array of values of type int, and the element-wise maximum is returned in the same array.

If a 'rank_of_max' argument is provided, it will set the array to the rank of process holding the maximum value. Like the double argument, the size of the supplied 'rank_of_max' array should be n.

void SAMRAI::tbox::SAMRAI_MPI::allToOneSumReduction	(	int *	x,
		const int	n,
		const int	root = 0
	)			[static]

Perform an all-to-one sum reduction on an integer array. The final result is only available on the root processor.

int SAMRAI::tbox::SAMRAI_MPI::bcast	(	const int	x,
		const int	root
	)			[static]

Broadcast integer from specified root process to all other processes. All processes other than root, receive a copy of the integer value.

void SAMRAI::tbox::SAMRAI_MPI::bcast	(	int *	x,
		int &	length,
		const int	root
	)			[static]

Broadcast integer array from specified root processor to all other processors. For the root processor, "array" and "length" are treated as const.

void SAMRAI::tbox::SAMRAI_MPI::bcast	(	char *	x,
		int &	length,
		const int	root
	)			[static]

Broadcast char array from specified root processor to all other processors. For the root processor, "array" and "length" are treated as const.

void SAMRAI::tbox::SAMRAI_MPI::send	(	const int *	buf,
		const int	length,
		const int	receiving_proc_number,
		const bool	send_length = true,
		int	tag = -1
	)			[static]

This function sends an MPI message with an integer array to another processer.

If the receiving processor knows in advance the length of the array, use "send_length = false;" otherwise, this processor will first send the length of the array, then send the data. This call must be paired with a matching call to SAMRAI_MPI::recv.

Parameters:

	buf	Pointer to integer array buffer with length integers.
	length	Number of integers in buf that we want to send.
	receiving_proc_number	Receiving processor number.
	send_length	Optional boolean argument specifiying if we first need to send a message with the array size. Default value is true.
	tag	Optional integer argument specifying an integer tag to be sent with this message. Default tag is 0.

void SAMRAI::tbox::SAMRAI_MPI::sendBytes	(	const void *	buf,
		const int	number_bytes,
		const int	receiving_proc_number
	)			[static]

This function sends an MPI message with an array of bytes (MPI_BYTES) to receiving_proc_number.

This call must be paired with a matching call to SAMRAI_MPI::recvBytes.

Parameters:

	buf	Void pointer to an array of number_bytes bytes to send.
	number_bytes	Integer number of bytes to send.
	receiving_proc_number	Receiving processor number.

int SAMRAI::tbox::SAMRAI_MPI::recvBytes	(	void *	buf,
		int	number_bytes
	)			[static]

This function receives an MPI message with an array of max size number_bytes (MPI_BYTES) from any processer.

This call must be paired with a matching call to SAMRAI_MPI::sendBytes.

This function returns the processor number of the sender.

Parameters:

	buf	Void pointer to a buffer of size number_bytes bytes.
	number_bytes	Integer number specifing size of buf in bytes.

void SAMRAI::tbox::SAMRAI_MPI::recv	(	int *	buf,
		int &	length,
		const int	sending_proc_number,
		const bool	get_length = true,
		int	tag = -1
	)			[static]

This function receives an MPI message with an integer array from another processer.

If this processor knows in advance the length of the array, use "get_length = false;" otherwise, the sending processor will first send the length of the array, then send the data. This call must be paired with a matching call to SAMRAI_MPI::send.

Parameters:

	buf	Pointer to integer array buffer with capacity of length integers.
	length	Maximum number of integers that can be stored in buf.
	sending_proc_number	Processor number of sender.
	get_length	Optional boolean argument specifiying if we first need to send a message to determine the array size. Default value is true.
	tag	Optional integer argument specifying a tag which must be matched by the tag of the incoming message. Default tag is 0.

void SAMRAI::tbox::SAMRAI_MPI::allGather	(	const int *	x_in,
		int	size_in,
		int *	x_out,
		int	size_out
	)			[static]

Each processor sends an array of integers or doubles to all other processors; each processor's array may differ in length. The x_out array must be pre-allocated to the correct length (this is a bit cumbersome, but is necessary to avoid th allGather function from allocating memory that is freed elsewhere). To properly preallocate memory, before calling this method, call

size_out = SAMRAI_MPI::sumReduction(size_in)

then allocate the x_out array.

void SAMRAI::tbox::SAMRAI_MPI::allGather	(	const double *	x_in,
		int	size_in,
		double *	x_out,
		int	size_out
	)			[static]

void SAMRAI::tbox::SAMRAI_MPI::allGather	(	int	x_in,
		int *	x_out
	)			[static]

Each processor sends every other processor an integer or double. The x_out array should be preallocated to a length equal to the number of processors.

void SAMRAI::tbox::SAMRAI_MPI::allGather	(	double	x_in,
		double *	x_out
	)			[static]

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Member Data Documentation

SAMRAI_MPI::comm SAMRAI::tbox::SAMRAI_MPI::commWorld [static]

MPI constants

SAMRAI_MPI::comm SAMRAI::tbox::SAMRAI_MPI::commNull [static]

---

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

• source/toolbox/parallel/SAMRAI_MPI.h
• source/toolbox/parallel/SAMRAI_MPI.C
• source/toolbox/parallel/SAMRAI_MPI.I

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