Geant4 parameters for tracking in field

[civanch]

PR description:

For a long time non-optimal parameters for Geant4 tracking in field were used in order do not change simulation histories and not redo full validation for UL. In this PR few CMS/G4 magnetic field parameters are change, that will provoke many differences in regression. The CPU effects is expected to be minor, number of warnings from Geant4 tracking in field should be reduced dramatically. This seems to be useful for deployment of the coming Geant4 10.6.

PR validation:

private

if this PR is a backport please specify the original PR:

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[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-27789/11477

• This PR adds an extra 16KB to repository

[civanch]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/2054/console Started: 2019/08/16 11:48

[cmsbuild]

A new Pull Request was created by @civanch (Vladimir Ivantchenko) for master.

It involves the following packages:

SimG4Core/Application

@cmsbuild, @civanch, @mdhildreth can you please review it and eventually sign? Thanks.
@makortel this is something you requested to watch as well.
@davidlange6, @slava77, @fabiocos you are the release manager for this.

cms-bot commands are listed here

[cmsbuild]

+1
Tested at: 8c9605d
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-895bc5/2054/summary.html

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-895bc5/2054/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 41094 differences found in the comparisons
• DQMHistoTests: Total files compared: 34
• DQMHistoTests: Total histograms compared: 2939508
• DQMHistoTests: Total failures: 122119
• DQMHistoTests: Total nulls: 5
• DQMHistoTests: Total successes: 2817043
• DQMHistoTests: Total skipped: 341
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 7.525 KiB( 33 files compared)
• DQMHistoSizes: changed ( 250202.181 ): 0.767 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 8.0 ): 6.473 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 25202.0 ): 0.628 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 7.3 ): -0.343 KiB SiStrip/MechanicalView
• Checked 142 log files, 14 edm output root files, 34 DQM output files

[civanch]

+1
differences are expected

[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, @slava77, @smuzaffar, @fabiocos (and backports should be raised in the release meeting by the corresponding L2)

[fabiocos]

@civanch comparing performance differences in the JobReport for 11634.0 vs to the baseline does not show very significant changes, that can be trusted on such a small statistics. Which kind of effect would you expect? The maximum step size is reduced, so I would expect on average a bit more steps...

[fabiocos]

+1

[civanch]

@fabiocos , I would expect more number of steps in vacuum and in air, in particular, less number of circles from low energy looping e+-. For example, before this PR geometry step limitation inside CMS vacuum tube is up to 3 m.