shmem_quiet.3.rst

shmem_quiet

:ref:`shmem_quiet`(3) - Waits for completion of all outstanding remote writes issued by a processing element (PE).

SYNOPSIS

C or C++:

#include <mpp/shmem.h>

void shmem_quiet(void)

Fortran:

CALL SHMEM_QUIET

DESCRIPTION

:ref:`shmem_quiet` ensures ordering of put (remote write) operations. All put operations issued to any processing element (PE) prior to the call to :ref:`shmem_quiet` are guaranteed to be visible to all other PEs no later than any subsequent memory load or store, remote put or get, or synchronization operations that follow the call to :ref:`shmem_quiet`.

NOTES

:ref:`shmem_quiet` is most useful as a way of ensuring ordering of delivery of several put operations. For example, you might use :ref:`shmem_quiet` to await delivery of a block of data before issuing another put, which sets a completion flag on another PE.

:ref:`shmem_quiet` is not usually needed if :ref:`shmem_barrier_all`(3) or :ref:`shmem_barrier`(3) are called. The barrier routines all wait for the completion of outstanding remote writes (puts).

EXAMPLES

PROGRAM COMPFLAG
  INCLUDE "mpp/shmem.fh"

  INTEGER FLAG_VAR, ARRAY(100), RECEIVER, SENDER
  COMMON/FLAG/FLAG_VAR
  COMMON/DATA/ARRAY
  INTRINSIC MY_PE

  FLAG_VAR = 0
  CALL SHMEM_BARRIER_ALL ! wait for FLAG_VAR to be initialized
  SENDER = 0                        ! PE 0 sends the data
  RECEIVER = 1                      ! PE 1 receives the data

  IF (MY_PE() .EQ. 0) THEN
    ARRAY = 33
    CALL SHMEM_PUT(ARRAY, ARRAY, 100, RECEIVER) ! start sending data
    CALL SHMEM_QUIET                ! wait for delivery
    CALL SHMEM_PUT(FLAG_VAR, 1, 1, RECEIVER) ! send completion flag
  ELSE IF (MY_PE() .EQ. RECEIVER) THEN
    CALL SHMEM_UDCFLUSH
    CALL SHMEM_WAIT(FLAG_VAR, 0)
    PRINT *,ARRAY                       ! ARRAY has been delivered
  ENDIF
END

.. seealso::
   *intro_shmem*\ (3) :ref:`shmem_barrier`\ (3) :ref:`shmem_barrier_all`\ (3)
   *shmem_fence*\ (3) *shmem_put*\ (3) *shmem_wait*\ (3)