Data Distribution: Affinity

usage of AFFINITY clause:
- data form: thread form:

iterations are scheduled such that each processor does iterations over data that is placed in the memory near to that processor

REAL*8 A(N),B(N),Q

!$SGI DISTRIBUTE A(BLOCK),B(BLOCK)

C INITIALIZATION:

DO I=1,N

A(I) = 1 - I/2

B(I) = -10 + 0.01*(I*I)

ENDDO

C REAL WORK:

DO IT=1,NITERS

Q = 0.01*IT

C$OMP PARALLEL DO

C$SGI AFFINITY(I)=DATA(A(I))

DO I=1,N

A(I) = A(I) + Q*B(I)

ENDDO

ENDDO

REAL*8 A(N),B(N),Q

!$SGI DISTRIBUTE A(BLOCK),B(BLOCK)

C INITIALIZATION:

DO I=1,N

A(I) = 1 - I/2

B(I) = -10 + 0.01*(I*I)

ENDDO

C REAL WORK:

DO IT=1,NITERS

Q = 0.01*IT

C$OMP PARALLEL DO

C$SGI AFFINITY(I)=thread(I/(N/P))

DO I=1,N

A(I) = A(I) + Q*B(I)

ENDDO

ENDDO

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