Livelock

• This shows a race condition and a livelock.

• If the square of RES is never smaller than TOL, the program spins endlessly in Livelock.

C$OMP PARALLEL PRIVATE(ID)

ID = OMP_GET_THREAD_NUM()

N = OMP_GET_NUM_THREADS()

1000 CONTINUE

PHASES[ID] = UPDATE(U, ID)

C$OMP SINGLE

RES = MATCH (PHASES, N)

C$OMP END SINGLE

IF (RES*RES .LT. TOL) GO TO 2000

GO TO 1000

2000 CONTINUE

C$OMP END PARALLEL

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