Add a preference to disable Polyester

[vchuravy]

In order to study the performance of the Julia scheduler with Trixi,
I would like to be able to quickly jump between Polyster and Julia's scheduler.

This replaces #1768 with a prefernce switch, default is Polyster on.

Random observation on my AMD Ryzen 7 7840U on examples/tree_2d_dgsem/elixir_euler_sedov_blast_wave.jl
rhs! evaluation.

Polyster	NThreads	Time
Off	1	37.9s
Off	8	8.1s
On	1	29.6s
On	8	5.9s

So the question to solve first is why did the single threaded execution slow down.

[github-actions]

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[ranocha]

Thanks a lot! I just have a few suggestions.

[ranocha]

So the question to solve first is why did the single threaded execution slow down.

This could be related to the change of Trixi.wrap_array. You could try running the serial version with PtrArrays

[codecov]

Codecov Report

Attention: Patch coverage is 63.63636% with 4 lines in your changes missing coverage. Please review.

Project coverage is 96.23%. Comparing base (ed97031) to head (dda0c67).

Files	Patch %	Lines
src/auxiliary/math.jl	0.00%	3 Missing ⚠️
src/callbacks_step/summary.jl	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2029      +/-   ##
==========================================
- Coverage   96.24%   96.23%   -0.01%     
==========================================
  Files         462      462              
  Lines       37076    37084       +8     
==========================================
+ Hits        35683    35687       +4     
- Misses       1393     1397       +4     

Flag	Coverage Δ
unittests	96.23% <63.64%> (-0.01%)	⬇️

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[ranocha]

Thanks!

[ranocha]

Could you please run the formatter as described in the docs?

https://trixi-framework.github.io/Trixi.jl/stable/styleguide/#automated-source-code-formatting

We use JuliaFormatter v1.0.45

[JoshuaLampert]

Thanks! Please find two questions below.

[ranocha]

Thanks!

[ranocha]

I just see that set_sqrt_type also doesn't have a !, but, e.g., set_library_p4est! from P4est.jl has one.

@JoshuaLampert A PR deprecating set_sqrt_type in favor of a new set_sqrt_type! would be very welcome 🙂