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program openmp_64
use omp_lib
implicit none
integer, parameter :: n = 100
integer :: i, tid, j
real :: delay
integer :: thread_iterations(0:7) = 0
integer :: iteration_order(n)
integer :: order_counter
integer :: consecutive_count, max_consecutive
real :: work_array(n)
call omp_set_num_threads(4)
order_counter = 0
print *, "=== DYNAMIC Schedule Test ==="
! Dynamic schedule should NOT give contiguous blocks to threads
!$omp parallel do schedule(dynamic, 1) private(tid, delay)
do i = 1, n
tid = omp_get_thread_num()
! Simulate varying work to see dynamic behavior
if (mod(i, 10) == 0) then
! Some iterations take longer
delay = 0.0
do j = 1, 1000
delay = delay + sin(real(j))
end do
work_array(i) = delay
end if
!$omp critical
thread_iterations(tid) = thread_iterations(tid) + 1
order_counter = order_counter + 1
iteration_order(order_counter) = tid
!$omp end critical
end do
!$omp end parallel do
! Analyze dynamic behavior
print *, "Thread iteration counts:"
do i = 0, omp_get_max_threads()-1
print *, "Thread", i, ":", thread_iterations(i), "iterations"
end do
! Check that work is not always in large contiguous blocks
! Dynamic with chunk=1 should interleave frequently
max_consecutive = 0
consecutive_count = 1
do i = 2, n
if (iteration_order(i) == iteration_order(i-1)) then
consecutive_count = consecutive_count + 1
else
if (consecutive_count > max_consecutive) then
max_consecutive = consecutive_count
end if
consecutive_count = 1
end if
end do
print *, "Maximum consecutive iterations by same thread:", max_consecutive
! With dynamic(1), we shouldn't see very large consecutive blocks
if (max_consecutive > 10) then
print *, "WARNING: Dynamic schedule showing large consecutive blocks"
print *, "This might indicate dynamic scheduling is not working properly"
end if
! Check work distribution variation
! Dynamic should show more variation than static
if (maxval(thread_iterations(0:3)) - minval(thread_iterations(0:3)) < 2) then
print *, "WARNING: Work distribution too uniform for dynamic schedule"
end if
print *, "DYNAMIC schedule test completed"
end program openmp_64
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