feat: ingest EventHeader into digi, generate UID to reseed RNG #1934
+306
−109
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
github-actions
bot
added
topic: calorimetry
wdconinc
commented
Jun 27, 2025
Comment on lines
+43
to
+44
| size_t getUniqueID(const event_num_t evt_num, const run_num_t run_num, | ||
| const std::string_view& name) const { |
There was a problem hiding this comment.
Not strictly necessary to ingest name here, since can pass that on init, not process, but this is an attempt at sticking close to the k4FWCore approach. Only difference is that we take a string_view instead of a string (arguably they will want to move to string_view anyway).
for more information, see https://pre-commit.ci
|
Interesting... The new plots for MT and non-MT should now be identical... But aren't.
Maybe I'm missing some reseeding somewhere. |
Or there's a data race, https://github.com/eic/EICrecon/actions/runs/15937325592/job/44960208488?pr=1934#step:7:928 ... |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Briefly, what does this PR introduce?
One challenge of multi-threaded/concurrent running is that the random number generators are called in no predictable order; this affects both events which can come out of order, or algorithms within the same event which can be called in different orders for different branches. That results in non-reproducibility.
This PR ingests the event header into digitization algorithms (which is our main use for random sampling). The event header is combined with the algorithm name into a random seed for that event/algorithm combination. With this seed, the random number generator is reseeded.
Outside the scope of this PR is reverting back to a single random service instead of the various algorithm specific approaches.
Still TODO in this algorithm:
What kind of change does this PR introduce?
Please check if this PR fulfills the following:
Does this PR introduce breaking changes? What changes might users need to make to their code?
No.
Does this PR change default behavior?
Yes. It results in a different random number sequence, so all distributions will be shuffled.