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program openmp_68
use omp_lib
implicit none
integer, parameter :: n = 100
integer :: i, tid, j
integer :: thread_chunks(0:7) = 0
integer :: chunk_sizes(100) ! Track size of each chunk given out
integer :: chunk_count = 0
integer :: current_iteration = 1
integer :: chunk_start(100), chunk_thread(100)
logical :: test_passed = .true.
logical :: looks_like_static = .true.
call omp_set_num_threads(4)
print *, "=== DYNAMIC Schedule with chunk=", 5, "==="
! Track chunks
!$omp parallel private(tid)
!$omp do schedule(dynamic, 5)
do i = 1, n
tid = omp_get_thread_num()
!$omp critical
! Check if this is start of new chunk
if (i == current_iteration) then
chunk_count = chunk_count + 1
chunk_start(chunk_count) = i
chunk_thread(chunk_count) = tid
thread_chunks(tid) = thread_chunks(tid) + 1
! Find chunk size
if (i + 5 - 1 <= n) then
chunk_sizes(chunk_count) = 5
current_iteration = i + 5
else
chunk_sizes(chunk_count) = n - i + 1
current_iteration = n + 1
end if
end if
!$omp end critical
end do
!$omp end do
!$omp end parallel
! Verify dynamic chunk behavior
print *, "Total chunks distributed:", chunk_count
print *, "Chunks per thread:"
do i = 0, omp_get_max_threads()-1
print *, "Thread", i, ":", thread_chunks(i), "chunks"
end do
! Check chunk sizes
do i = 1, chunk_count-1
if (chunk_sizes(i) /= 5) then
print *, "ERROR: Chunk", i, "has size", chunk_sizes(i), "expected", 5
test_passed = .false.
end if
end do
! Last chunk might be smaller
if (chunk_sizes(chunk_count) > 5) then
print *, "ERROR: Last chunk too large!"
test_passed = .false.
end if
! With dynamic, chunks should not follow a strict pattern
! Check for round-robin pattern (which would indicate static behavior)
do i = 2, min(chunk_count, 8)
if (chunk_thread(i) /= mod(chunk_thread(1) + i - 1, omp_get_max_threads())) then
looks_like_static = .false.
exit
end if
end do
if (looks_like_static .and. chunk_count > 4) then
print *, "WARNING: Dynamic schedule showing static-like round-robin pattern!"
end if
if (.not. test_passed) then
error stop "DYNAMIC chunk schedule test FAILED!"
end if
print *, "DYNAMIC chunk schedule test completed"
end program openmp_68
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