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MPI_Put - Copies data from the origin memory to the target.
#include <mpi.h>
MPI_Put(void *origin_addr, int origin_count, MPI_Datatype
origin_datatype, int target_rank, MPI_Aint target_disp,
int target_count, MPI_Datatype target_datatype, MPI_Win win)
INCLUDE ’mpif.h’
MPI_PUT(ORIGIN_ADDR, ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
TARGET_DISP, TARGET_COUNT, TARGET_DATATYPE, WIN, IERROR)
<type> ORIGIN_ADDR(*)
INTEGER(KIND=MPI_ADDRESS_KIND) TARGET_DISP
INTEGER ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK, TARGET_COUNT,
TARGET_DATATYPE, WIN, IERROR
#include <mpi.h>
void MPI::Win::Put(const void* origin_addr, int origin_count, const
MPI::Datatype& origin_datatype, int target_rank, MPI::Aint
target_disp, int target_count, const MPI::Datatype&
target_datatype) const
- origin_addr
- Initial address of origin buffer (choice).
- origin_count
- Number of entries in origin buffer (nonnegative integer).
- origin_datatype
- Data type of each entry in origin buffer (handle).
- target_rank
- Rank of target
(nonnegative integer).
- target_disp
- Displacement from start of window to
target buffer (nonnegative integer).
- target_count
- Number of entries in target
buffer (nonnegative integer).
- target_datatype
- Data type of each entry in
target buffer (handle).
- win
- Window object used for communication (handle).
- IERROR
- Fortran only: Error status (integer).
MPI_Put
transfers origin_count successive entries of the type specified by origin_datatype,
starting at address origin_addr on the origin node to the target node specified
by the win, target_rank pair. The data are written in the target buffer
at address target_addr = window_base + target_disp x disp_unit, where window_base
and disp_unit are the base address and window displacement unit specified
at window initialization, by the target process.
The target buffer is specified
by the arguments target_count and target_datatype.
The data transfer is
the same as that which would occur if the origin process executed a send
operation with arguments origin_addr, origin_count, origin_datatype, target_rank,
tag, comm, and the target process executed a receive operation with arguments
target_addr, target_count, target_datatype, source, tag, comm, where target_addr
is the target buffer address computed as explained above, and comm is a
communicator for the group of win.
The communication must satisfy the same
constraints as for a similar message-passing communication. The target_datatype
may not specify overlapping entries in the target buffer. The message sent
must fit, without truncation, in the target buffer. Furthermore, the target
buffer must fit in the target window. In addition, only processes within
the same buffer can access the target window.
The target_datatype argument
is a handle to a datatype object defined at the origin process. However,
this object is interpreted at the target process: The outcome is as if
the target datatype object were defined at the target process, by the same
sequence of calls used to define it at the origin process. The target data
type must contain only relative displacements, not absolute addresses. The
same holds for get and accumulate.
The target_datatype argument is
a handle to a datatype object that is defined at the origin process, even
though it defines a data layout in the target process memory. This does
not cause problems in a homogeneous or heterogeneous environment, as long
as only portable data types are used (portable data types are defined in
Section 2.4 of the MPI-2 Standard).
The performance of a put transfer can
be significantly affected, on some systems, from the choice of window location
and the shape and location of the origin and target buffer: Transfers to
a target window in memory allocated by MPI_Alloc_mem may be much faster
on shared memory systems; transfers from contiguous buffers will be faster
on most, if not all, systems; the alignment of the communication buffers
may also impact performance.
The MPI standard prescribes
portable Fortran syntax for the TARGET_DISP argument only for Fortran 90.
FORTRAN 77 users may use the non-portable syntax
INTEGER*MPI_ADDRESS_KIND TARGET_DISP
where MPI_ADDRESS_KIND is a constant defined in mpif.h and gives the length
of the declared integer in bytes.
Almost all MPI routines return
an error value; C routines as the value of the function and Fortran routines
in the last argument. C++ functions do not return errors. If the default
error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the
C++ exception mechanism will be used to throw an MPI:Exception object.
Before
the error value is returned, the current MPI error handler is called. By
default, this error handler aborts the MPI job, except for I/O function
errors. The error handler may be changed with MPI_Comm_set_errhandler; the
predefined error handler MPI_ERRORS_RETURN may be used to cause error values
to be returned. Note that MPI does not guarantee that an MPI program can
continue past an error.
MPI_Get
MPI_Accumulate
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