run time -- some questions

[diedro]

Dear all, 

I have written a very long code, with many subroutines.

In this moment I am runnung some simple run-time analysis with 

   CALL CPU_TIME()

I have notice something strange. When I increase the number of cycle in may code the running time increases not linearly. 

I mean if I do four cycles instead of two, the running time does not double but is is greater. 

Now, I am looking to some convernce of my code. However, I would like if there are some possible other reasons to check in my code. For example some problem linked to subroutine call.

Thanks a lot

[jimdempseyatthecove]

Does your program memory requirement grow in size after each iteration (cycle).?

Does your code contain uninitialized variables? (run time may depend on junk or leftover data)

Are you taking your time intervals properly?

Jim Dempsey