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VERY slow computation!

Erin King, modified 6 Years ago.

VERY slow computation!

Youngling Posts: 4 Join Date: 10/5/16 Recent Posts
Hi,

I have recently started using Delft3D on a new PC which should provide performance gains over my current one. However this has only proved partly true. When running my model domain at 4km wave resolution the performance is better on the new PC. When running at 1km resolution the new PC slows down massively to the point where it is almost 10x slower on the new machine versus the old one! (both running the 1km model).

The idea behind the new PC was partly to allow us to move up to 1km resolution with the waves and so this is a problem.

The slow down appears to be in the Wait (ext. modules) section on the Performance timers output in the tri-diag files (see the images attached). I believe that is just reflecting that the slow down is in the wave computation which is visually apparent watching the iterations.

The new machine has an 8 core CPU with 16 threads VS a 6 core CPU. I have tried reducing the number of threads used by SWAN on the new PC, which speeds up the computation time marginally (enough to run the tests shown in the pictures) but the problem remains.

The new machine is Windows 10 VS Windows 7 on the old machine. Could it be an OS issue?

Any help or experience shared will be appreciated!

Cheers,
Erin