[petsc-users] Investigate parallel code to improve parallelism

[Barry Smith]

> On Feb 26, 2016, at 9:28 AM, TAY wee-beng <zonexo at gmail.com> wrote:
> 
> Hi,
> 
> I have got a 3D code. When I ran with 48 procs and 11 million cells, it runs for 83 min. When I ran with 96 procs and 22 million cells, it ran for 99 min.

   This is actually pretty good!

> 
> So it's not that parallel. I want to find out which part of the code I need to improve. Also if PETsc and hypre is working well in parallel. What's the best way to do it?

  Run both with -log_summary and send the output for each case. This will show where the time is being spent and which parts are scaling less well.

   Barry
> 
> I thought of doing profiling but if the code is optimized, I wonder if it still works well.
> 
> -- 
> Thank you.
> 
> Yours sincerely,
> 
> TAY wee-beng
>