Fix the MadGraph bug for multithreading (backport #30444)

[colizz]

PR description:

This PR is a backport from #30444

PR validation:

The fix is on shell scripts, hence does not influence the CMSSW framework.
We tested the scripts on W+01234j and DY+01234j multi-jet processes to validate that the MG bug is solved.

(A quick test for this PR on SMP-MultiValidationUL17wmLHEGEN-00001)

cmsrel CMSSW_10_6_X_2020-06-26-2300
cd CMSSW_10_6_X_2020-06-26-2300/src/
cmsenv
git cms-merge-topic colizz:dev-mt-106X
curl -s --insecure https://cms-pdmv.cern.ch/mcm/public/restapi/requests/get_fragment/SMP-MultiValidationUL17wmLHEGEN-00001 --retry 2 --create-dirs -o Configuration/GenProduction/python/SMP-MultiValidationUL17wmLHEGEN-00001-fragment.py 
scram b -j 8
cd ../..
cmsDriver.py Configuration/GenProduction/python/SMP-MultiValidationUL17wmLHEGEN-00001-fragment.py --fileout file:SMP-MultiValidationUL17wmLHEGEN-00001.root --mc --eventcontent RAWSIM,LHE --datatier GEN,LHE --conditions 106X_mc2017_realistic_v6 --beamspot Realistic25ns13TeVEarly2017Collision --step LHE,GEN --geometry DB:Extended --era Run2_2017 --python_filename SMP-MultiValidationUL17wmLHEGEN-00001_1_cfg.py --no_exec --customise Configuration/DataProcessing/Utils.addMonitoring -n 400 --nThreads 4

cmsRun -e -j SMP-MultiValidationUL17wmLHEGEN-00001_rt.xml SMP-MultiValidationUL17wmLHEGEN-00001_1_cfg.py

[cmsbuild]

A new Pull Request was created by @colizz (Congqiao Li) for CMSSW_10_6_X.

It involves the following packages:

GeneratorInterface/LHEInterface

@SiewYan, @mkirsano, @cmsbuild, @GurpreetSinghChahal, @agrohsje, @alberto-sanchez, @qliphy can you please review it and eventually sign? Thanks.
@alberto-sanchez, @agrohsje, @mkirsano this is something you requested to watch as well.
@silviodonato, @dpiparo you are the release manager for this.

cms-bot commands are listed here

[qliphy]

please test

[cmsbuild]

The tests are being triggered in jenkins.

• CMSSW_10_6_X_2020-06-27-1100/slc7_amd64_gcc700: https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/7472/console Started: 2020/06/29 06:18

[cmsbuild]

+1
Tested at: 8786954
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-4a003f/7472/summary.html
CMSSW: CMSSW_10_6_X_2020-06-27-1100
SCRAM_ARCH: slc7_amd64_gcc700

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-4a003f/7472/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 34
• DQMHistoTests: Total histograms compared: 3214558
• DQMHistoTests: Total failures: 2
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3214222
• DQMHistoTests: Total skipped: 334
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 33 files compared)
• Checked 140 log files, 14 edm output root files, 34 DQM output files

[qliphy]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_10_6_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_11_2_X is complete. This pull request will now be reviewed by the release team before it's merged. @silviodonato, @dpiparo (and backports should be raised in the release meeting by the corresponding L2)

[silviodonato]

+1