Create a fresh ArrayEventContainer for each event in SimTelEventSource

[maxnoe]

Seems to have no impact on performance:

This branch:

SimTelEventSource: 1010ev [00:46, 21.70ev/s]

Master:

SimTelEventSource: 1010ev [00:46, 21.66ev/s]

I was bitten by the reuse of the container again, this time it was DL2 information from the previous events not being cleared.

[kosack]

yeah if there is no performance impact, this is definitely a good idea. all there reuse was originally just for performance, but i have to admit i never measured it.

i’m considering even replacing the current Container implementation with a dataclass based one, with frozen attributes. I tried it and it seems to be must as fast and would prevent most accidental changes if we’re required to fill all containers at creation time

[codecov]

Codecov Report

Merging #1952 (ebb90e8) into master (31a0fcc) will decrease coverage by 0.00%.
The diff coverage is 92.59%.

@@            Coverage Diff             @@
##           master    #1952      +/-   ##
==========================================
- Coverage   92.20%   92.20%   -0.01%     
==========================================
  Files         193      193              
  Lines       15216    15203      -13     
==========================================
- Hits        14030    14018      -12     
+ Misses       1186     1185       -1     

Impacted Files	Coverage Δ
ctapipe/io/simteleventsource.py	95.47% <92.59%> (+0.16%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 31a0fcc...ebb90e8. Read the comment docs.

[maxnoe]

i’m considering even replacing the current Container implementation with a dataclass based one,

That won't have all our features like prefixes / data types / help strings etc. dataclasses are a very powerful code generator, but in the end you get normal python classes with some fields. We have our own code generator here (that's essentially what the ContainerMeta class is, a code generator) that's I think better suited than starting over from dataclasses.

E.g. we have __slots__, dataclasses don't support that I think

[LukasNickel]

I think this is a good idea.
Avoids all the subtle bugs with reused information