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MPI_Put, MPI_Rput - Copies data from the origin memory to the
target.
#include <mpi.h>
MPI_Put(const 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)
MPI_Rput(const 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,
MPI_Request *request)
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
MPI_RPUT(ORIGIN_ADDR, ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
TARGET_DISP, TARGET_COUNT, TARGET_DATATYPE, WIN, REQUEST, IERROR)
<type> ORIGIN_ADDR(*)
INTEGER(KIND=MPI_ADDRESS_KIND) TARGET_DISP
INTEGER ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK, TARGET_COUNT,
TARGET_DATATYPE, WIN, REQUEST, 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).
- request
- MPI_Rput: RMA request
- 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.
MPI_Rput is similar to MPI_Put, except that it allocates
a communication request object and associates it with the request handle
(the argument request). The completion of an MPI_Rput operation (i.e., after
the corresponding test or wait) indicates that the sender is now free to
update the locations in the origin_addr buffer. It does not indicate that
the data is available at the target window. If remote completion is required,
MPI_Win_flush, MPI_Win_flush_all, MPI_Win_unlock, or MPI_Win_unlock_all
can be used.
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_Rget
MPI_Accumulate MPI_Win_flush MPI_Win_flush_all MPI_Win_unlock MPI_Win_unlock_all
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