Peak fit parallelization

[borondics]

Since we have problems with the parallel fitting I was thinking if we could simply use Dask for this?

[stuart-cls]

As far as I know, the problem is fixed (#748)! If not, we need a new bug :)

Dask is another good option for parallelization but we don't have dask in our standard release.

[borondics]

Yes, it is working now, but only using one core, right?

[stuart-cls]

Two processes by default, but you can override on beefier machines by setting an environment variable:

By default this is limited to 2 extra processes, but this can be
overridden by setting the environment variable QUASAR_N_PROCESSES to the desired number, or all
to use the default value returned by os.cpu_count().

I put it in the docs but it's not showing up on https://orange-spectroscopy.readthedocs.io/en/latest/widgets/peakfit.html 🧐

[stuart-cls]

Fixed the readthedocs.

[markotoplak]

Thanks, @stuart-cls.

[borondics]

@stuart-cls, I was just thinking about this environment variable. Would it make more sense to have a setting somewhere in Quasar? Either in the menu or the widget itself?