Interface ICommunicator

Namespace: Microsoft.ML.Probabilistic

Assembly: Microsoft.ML.Probabilistic.dll

Syntax

public interface ICommunicator

Properties

PercentTimeSpentWaiting

Declaration

double PercentTimeSpentWaiting { get; }

Property Value

Type	Description
Double

Rank

Identifies the currently executing process within this communicator.

Declaration

int Rank { get; }

Property Value

Type	Description
Int32

Size

The number of processes within this communicator.

Declaration

int Size { get; }

Property Value

Type	Description
Int32

Methods

Allreduce<T>(T, Func<T, T, T>)

Allreduce is a collective algorithm that combines the values stored by each process into a
single value available to all processes. The values are combined in a user-defined way, specified via
a delegate. If value1, value2, ..., valueN are the values provided by the
N processes in the communicator, the result will be the value value1 op value2 op ... op valueN.

An Allreduce is equivalent to a Reduce<T>(T, MPI.ReductionOperation<T>, int) followed by a Broadcast<T>(ref T, int)

Declaration

T Allreduce<T>(T value, Func<T, T, T> op)

Parameters

Type	Name	Description
T	value	The local value that will be combined with the values provided by other processes.
Func<T, T, T>	op	The operation used to combine two values. This operation must be associative.

Returns

Type	Description
T	The result of the reduction. The same value will be returned to all processes.

Type Parameters

Name	Description
T	Any serializable type.

Alltoall<T>(T[])

Collective operation in which every process sends data to every other process. Alltoall differs from Allgather<T>(T) in that a given process can send different data to all of the other processes, rather than contributing the same piece of data to all processes.

Declaration

T[] Alltoall<T>(T[] values)

Parameters

Type	Name	Description
T[]	values	The array of values that will be sent to each process. The ith value in this array will be sent to the process with rank i.

Returns

Type	Description
T[]	An array of values received from all of the other processes. The jth value in this array will be the value sent to the calling process from the process with rank j.

Type Parameters

Name	Description
T	Any serializable type.

AlltoallFlattened<T>(T[], Int32[], Int32[])

Collective operation in which every process sends data to every other process. Alltoall differs from Allgather<T>(T) in that a given process can send different data to all of the other processes, rather than contributing the same piece of data to all processes.

Declaration

T[] AlltoallFlattened<T>(T[] inValues, int[] sendCounts, int[] recvCounts)

Parameters

Type	Name	Description
T[]	inValues	The array of values that will be sent to each process. sendCounts[i] worth of data will be sent to process i.
Int32[]	sendCounts	The numbers of items to be sent to each process.
Int32[]	recvCounts

Returns

Type	Description
T[]	The array of values received from all of the other processes.

Type Parameters

Name	Description
T	Any serializable type.

Barrier()

Wait until all processes in the communicator have reached the same barrier.

Declaration

void Barrier()

Broadcast<T>(ref T, Int32)

Broadcast a value from the root process to all other processes.

Declaration

void Broadcast<T>(ref T value, int root)

Parameters

Type	Name	Description
T	value	The value to be broadcast. At the root process, this value is read (but not written); at all other processes, this value will be replaced with the value at the root.
Int32	root	The rank of the process that is broadcasting the value out to all of the non-root processes.

Type Parameters

Name	Description
T	Any serializable type.

Gather<T>(T, Int32)

Gather the values from each process into an array of values at the root process. On the root process, the pth element of the result will be equal to the value parameter of the process with rank p when this routine returns. Other processes receive null.

Declaration

T[] Gather<T>(T value, int root)

Parameters

Type	Name	Description
T	value	The value contributed by this process.
Int32	root	The rank of the process that will receive values for all of the processes in the communicator.

Returns

Type	Description
T[]

Type Parameters

Name	Description
T	Any serializable type.

GatherFlattened<T>(T[], Int32)

Similar to Gather<T>(T, Int32) but here all values are aggregated into one large array.

Declaration

T[] GatherFlattened<T>(T[] inValues, int root)

Parameters

Type	Name	Description
T[]	inValues	The values to be contributed by this process.
Int32	root	The rank of the root node.

Returns

Type	Description
T[]	The aggregated gathered values.

Type Parameters

Name	Description
T	Any serializable type.

ImmediateSend<T>(T, Int32, Int32)

Non-blocking send to a particular processor.

Declaration

ICommunicatorRequest ImmediateSend<T>(T value, int dest, int tag)

Parameters

Type	Name	Description
T	value
Int32	dest
Int32	tag

Returns

Type	Description
ICommunicatorRequest

Type Parameters

Name	Description
T

ImmediateSend<T>(T[], Int32, Int32)

Declaration

ICommunicatorRequest ImmediateSend<T>(T[] values, int dest, int tag)

Parameters

Type	Name	Description
T[]	values
Int32	dest
Int32	tag

Returns

Type	Description
ICommunicatorRequest

Type Parameters

Name	Description
T

Receive<T>(Int32, Int32, out T)

Blocking receive from a particular processor.

Declaration

void Receive<T>(int source, int tag, out T value)

Parameters

Type	Name	Description
Int32	source
Int32	tag
T	value

Type Parameters

Name	Description
T

Receive<T>(Int32, Int32, ref T[])

Blocking receive an array from a particular processor. Must have a matching array send.

Declaration

void Receive<T>(int source, int tag, ref T[] values)

Parameters

Type	Name	Description
Int32	source
Int32	tag
T[]	values	Must be allocated to the correct size. Cannot be null.

Type Parameters

Name	Description
T

Reduce<T>(T, Func<T, T, T>, Int32)

Reduce is a collective algorithm that combines the values stored by each process into a single value available at the designated root process. The values are combined in a user-defined way, specified via a delegate. If value1, value2, ..., valueN are the values provided by the N processes in the communicator, the result will be the value value1 op value2 op ... op valueN. This result is only available to the root process.

Declaration

T Reduce<T>(T value, Func<T, T, T> op, int root)

Parameters

Type	Name	Description
T	value	The local value that will be combined with the values provided by other processes.
Func<T, T, T>	op	The operation used to combine two values. This operation must be associative.
Int32	root	The rank of the process that is the root of the reduction operation, which will receive the result of the reduction operation.

Returns

Type	Description
T	On the root, returns the result of the reduction operation. The other processes receive a default value.

Type Parameters

Name	Description
T	Any serializable type.

Scatter<T>(T[], Int32)

Scatters an array of values by sending the ith value of the array to processor i.

Declaration

T Scatter<T>(T[] values, int root)

Parameters

Type	Name	Description
T[]	values	An array of values of length Size, which is only significant at the root. The ith value of this array (at the root process) will be sent to the ith processor.
Int32	root	Rank of the "root" process, which will supply the array of values to be scattered.

Returns

Type	Description
T

Type Parameters

Name	Description
T	Any serializable type.

Send<T>(T, Int32, Int32)

Blocking send to a particular processor. Will wait until the value is received.

Declaration

void Send<T>(T value, int dest, int tag)

Parameters

Type	Name	Description
T	value
Int32	dest
Int32	tag

Type Parameters

Name	Description
T

Send<T>(T[], Int32, Int32)

Blocking send array to a particular processor. Will wait until the value is received. Must be received by the array-specific receive method.

Declaration

void Send<T>(T[] values, int dest, int tag)

Parameters

Type	Name	Description
T[]	values
Int32	dest
Int32	tag

Type Parameters

Name	Description
T