[HGCal] Add a lower limit to the fraction of recHits energy in realistic SimClusters

[felicepantaleo]

PR description:

When a realistic simcluster becomes invisible, all its exclusive rechits are redistributed to every visible simcluster that has at least one hit in common with it.
In pathological events, this could lead to an increase of hits per realistic simcluster, with fractions below 1e-10, making the loop much longer.
Changes expected:

• decrease in the running time for pathological events
• decrease in the number of rechits per PFCluster with negligible change in energy

PR validation:

I have executed step3 of wf 23203.0 on one pathological event provided by the HLT upgrade convener @trtomei

[felicepantaleo]

@rovere fyi

[cmsbuild]

The code-checks are being triggered in jenkins.

[felicepantaleo]

@cmsbuild please test

[cmsbuild]

-code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-28976/13806

• This PR adds an extra 16KB to repository

Code check has found code style and quality issues which could be resolved by applying following patch(s)

• code-format:
  https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-28976/13806/code-format.patch
  e.g. curl https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-28976/13806/code-format.patch | patch -p1
  You can also run scram build code-format to apply code format directly

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-28976/13807

• This PR adds an extra 16KB to repository

[cmsbuild]

A new Pull Request was created by @felicepantaleo (Felice Pantaleo) for master.

It involves the following packages:

RecoParticleFlow/PFClusterProducer

@perrotta, @cmsbuild, @slava77 can you please review it and eventually sign? Thanks.
@mmarionncern, @clelange, @riga, @cbernet, @rovere, @lgray, @bachtis, @lecriste, @hatakeyamak, @seemasharmafnal this is something you requested to watch as well.
@davidlange6, @silviodonato, @fabiocos you are the release manager for this.

cms-bot commands are listed here

[slava77]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/4708/console Started: 2020/02/17 18:35

[cmsbuild]

+1
Tested at: e68e48a
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7ac2df/4708/summary.html
CMSSW: CMSSW_11_1_X_2020-02-17-1100
SCRAM_ARCH: slc7_amd64_gcc820

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7ac2df/4708/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 34
• DQMHistoTests: Total histograms compared: 2694005
• DQMHistoTests: Total failures: 1
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2693658
• DQMHistoTests: Total skipped: 346
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 33 files compared)
• Checked 147 log files, 16 edm output root files, 34 DQM output files

[slava77]

+1

for #28976 e68e48a

• code changes are in line with the PR description
• jenkins tests pass and comparisons with the baseline show no differences (the conditions addressed by this PR require some larger occupancy to show any difference).
• tested on 200 events with PU 300 D49 setup, running RECO:hgcalLocalRecoSequence in CMSSW_11_1_X_2020-02-19-1100: the CPU time in particleFlowClusterHGCal went down from an average of 14 s/ev with a variance of 59 s (max 756 s/ev) to an average of 2.1 s/ev with a variance of just 0.5 s.

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @davidlange6, @silviodonato, @fabiocos (and backports should be raised in the release meeting by the corresponding L2)

[silviodonato]

+1