Default Distribution: “First Touch”

• IRIX strategy for data placement:

  • respect program distribution directives
  • allocation on the node where data is initialized
  • allocation on the node where memory is available

PARAMETER (PAGESIZE=16384, SIZEDBLE=8)

REAL, ALLOCATABLE:: WORK(:)!! Distribution directive not available

READ *, MX

ALLOCATE(WORK(MX))

!$OMP PARALLEL DEFAULT(PRIVATE) SHARED(WORK,MX)

ID = OMP_GET_THREAD_NUM()

NP = OMP_GET_NUM_THREADS()

NPAGES = MX*SIZEDBLE/PAGESIZE

DO I=ID,NPAGES-NP+1,NP !! round-robin distribution of pages:

WORK(1+I*PAGESIZE/SIZEDBLE) = 0.0

ENDDO

!$OMP END PARALLEL

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