Fixing online behaviour of DQMFileSaverPB

[Sam-Harper]

PR description:

This PR is a bug fix to the recent DQM revamp which solely effects the HLT when run by the DAQ. For hltd to properly collect and merge the dqm histogram stream produced by the HLT, it needs a init file to be written. Otherwise the stream is ignored and at best the histograms are lost.

This PR adds that code. It should have no effect on any offline test, this only effects P5 running.

PR validation:

The hilton tests successfully produced the DQM Histogram stream.

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-29924/15537

• This PR adds an extra 16KB to repository

[cmsbuild]

A new Pull Request was created by @Sam-Harper (Sam Harper) for master.

It involves the following packages:

DQMServices/FileIO

@andrius-k, @kmaeshima, @schneiml, @cmsbuild, @jfernan2, @fioriNTU can you please review it and eventually sign? Thanks.
@barvic this is something you requested to watch as well.
@silviodonato, @dpiparo you are the release manager for this.

cms-bot commands are listed here

[jfernan2]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/6469/console Started: 2020/05/20 20:08

[cmsbuild]

+1
Tested at: e9f03c7
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-03ce7a/6469/summary.html
CMSSW: CMSSW_11_1_X_2020-05-19-2300
SCRAM_ARCH: slc7_amd64_gcc820

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-03ce7a/6469/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 35
• DQMHistoTests: Total histograms compared: 2694466
• DQMHistoTests: Total failures: 2
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2694415
• DQMHistoTests: Total skipped: 49
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 34 files compared)
• Checked 150 log files, 16 edm output root files, 35 DQM output files

[jfernan2]

+1

[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. @silviodonato, @dpiparo (and backports should be raised in the release meeting by the corresponding L2)

[silviodonato]

+1