AGRIF and optimization levels

Versions v4.2.x
1

Hi,
with previous code versions it was recommended to not go beyond optimization level -O1 when compiling a configuration with AGRIF. Is this still the case in NEMO4.2(.2)? How far can one go with the optimization without causing issues?
Thanks!
Franziska

2

Hello,
I did not try -O3, but in my Nemo 4.2.0-AGRIF config, -O2 works without surprises.
Cheers,
Luc

3

Thanks Luc for sharing your experience.
In the meantime I did some performance tests in NEMO4.2.2 (so far without evaluation of the physical solutions), resulting in decreasing performance (increasing runtimes) with increasing levels of optimization (-O1, -O2, -O3), which is kind of counter-intuitive. Any ideas on that?
For the time being I’ll stick to -O1.

4

I just did a quick test with my AGRIF simulation done with NEM 4.2.2 and for me, the optimization level -O3 is faster that -O1 by about 15%.

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