oracular (3) shmem_quiet.openmpi.3.gz

NAME

       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

       shmem_quiet ensures ordering of  put  (remote  write)  operations.  All  put  operations  issued  to  any
       processing element (PE) prior to the call to 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 shmem_quiet.

NOTES

       shmem_quiet  is  most  useful  as  a  way of ensuring ordering of delivery of several put operations. For
       example, you might use shmem_quiet to await delivery of a block of data before issuing another put, which
       sets a completion flag on another PE.
       shmem_quiet  is  not  usually  needed if shmem_barrier_all(3) or 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

SEE ALSO

       intro_shmem(3), shmem_barrier(3), shmem_barrier_all(3), shmem_fence(3), shmem_put(3), shmem_wait(3)