Dear David,Well, to let us examine your problem, you need to describe what *technicaly* does your program. ie: lots of disk access, lots of networks acces, lots of CPU access, allocate huge memory... in particular, is it CPU bound or I/O bound? You should also mention how tasks/thread is your program composed of.
The program is an atmospheric chemistry-transport modeling code that computes the distributions of atmospheric species (e.g., ozone) as a function of latitude and altitude and how that changes with time.
To answer briefly your question, _in general_ a program which takes more than a few seconds to execute should take roughly the same time to execute all the times.
Thanks for taking time to think about my problem. I greatly appreciate it.