[Omp] Still on the barrier

[Shengyan Hong]

Every OMP member,
         Thank you for your explanation.
         Now I'd like to mention my question in detail. I am looking for 
your help.
         Suppose there are 8 processors. Each has different frequencies and 
L1 cache latencies. For example, Cpu1 has 1.1 GHz and its L1 cache latency 
is 2 cycle.
         Suppose there are 8 threads in one benchmark. Suppose there is one 
barrier for these 8 threads. Suppose these 8 threads are divided into the 
8 processors.  Now I want to utilize the simics to test the idle time in 
the barrier for these 8 processors.
         I choose the benchmark FT.  I think that the code should be 
parallelized, so I choose the code as below:
!$omp parallel do default(shared) private(i,j,k)
       do k = 1, d3
          do j = 1, d2
             do i = 1, d1
                u0(i,j,k) = 0.d0
                u1(i,j,k) = 0.d0
                indexmap(i,j,k) = 0.d0
             end do
          end do
       end do

       return
       end
And change the code to be:
!$omp parallel do default(shared) private(i,j,k)
       do k = 1, d3
C       TID = OMP_GET_THREAD_NUM()
C       PRINT *, 'thread = ', TID
C       print *, "March 9"
        CALL MAGIC_BRK_SIM_START()
          do j = 1, d2
             do i = 1, d1
                u1(i,j,k) = u0(i,j,k)*ex(t*indexmap(i,j,k))
             end do
          end do
C       print *, "Before barrier"
        CALL MAGIC_BRK_SIM_MIDDLE()
C       !$OMP BARRIER
C       print *, "After barrier"
        CALL MAGIC_BRK_SIM_STOP()
        end do
      Now I get the idle time by using MAGIC_BRK_SIM_MIDDLE() and 
MAGIC_BRK_SIM_STOP. But each processor has the same idle time 6 cycles. 
Besides, I test the execution time by using MAGIC_BRK_SIM_START() and 
MAGIC_BRK_SIM_MIDDLE(). And each processor has different execution time. 
But no too different. For example, 1.7821*10^5 and 1.78345*10^5.
      Since you tell me that barrier can not be added into the parallel 
region. Now can you tell me where I can add the barrier. I think that the 
place of the code should have 8 threads. Right? To the end, how can I use 
barrier in the fortran code? Thank you very much.
                                              Shengyan Hong