enable testing DDP examples

[Borda]

What does this PR do?

enable DDP test for example

Resolves #4694

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[Borda]

seems that the DDP is hanging...

[tchaton]

Drone are breaking. When resolved, LGTM !

[awaelchli]

@Borda by how much will this increase drone test runtime?

[justusschock]

I think, we should only run this nightly with a cron job or so. Because when we run this more often, we will significantly slow down the development process, as we already experience some bottlenecks with iron and then it would pile up even more.

[Borda]

I think, we should only run this nightly with a cron job or so. Because when we run this more often, we will significantly slow down the development process, as we already experience some bottlenecks with iron and then it would pile up even more.

well then you can say the same for each test we run, we can run a test just nightly :]
if we want some simplification we shall skip all code testing for pure doc changes...

[tchaton]

LGTM !

[justusschock]

I think, we should only run this nightly with a cron job or so. Because when we run this more often, we will significantly slow down the development process, as we already experience some bottlenecks with iron and then it would pile up even more.

well then you can say the same for each test we run, we can run a test just nightly :]
if we want some simplification we shall skip all code testing for pure doc changes...

I don't think so. There's a difference in running unit tests and examples (which are basically some kind of integration/functionality testing).

[awaelchli]

I very much agree with Justus on this one

[Borda]

I don't think so. There's a difference in running unit tests and examples (which are basically some kind of integration/functionality testing).

so you say we shall drop the test and simply call the script in a command-line as another entry after python -m pytest

[Borda]

@justusschock @awaelchli this is what you had in mind b26adda?

[awaelchli]

it looks like this would still run on every commit/PR?

[codecov]

Codecov Report

Merging #4995 (eb54f18) into master (b295029) will decrease coverage by 0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #4995   +/-   ##
======================================
- Coverage      90%     90%   -0%     
======================================
  Files         170     170           
  Lines       11807   11807           
======================================
- Hits        10676   10646   -30     
- Misses       1131    1161   +30     

[Borda]

it looks like this would still run on every commit/PR?

yes, or what is your suggestion, just at midnight, but then we do not know what PR breaks it... (well, stop it which would break it...)

[Borda]

@justusschock @awaelchli so whall we keep this DDP testing or just drop it to run it only on master?

[tchaton]

LGTM !