Make calls to TH2F::Projection thread-safe #21995
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The histogram returned from TH2F::Projection* may be the same one as another thread if the name given is the same across the threads. Using a unique name and using a TDirectory::TContext will prevent the sharing across threads.
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The code-checks are being triggered in jenkins. |
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please test |
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+code-checks Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-21995/3085 |
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The tests are being triggered in jenkins. |
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A new Pull Request was created by @Dr15Jones (Chris Jones) for master. It involves the following packages: RecoVertex/BeamSpotProducer @perrotta, @ghellwig, @arunhep, @cerminar, @cmsbuild, @franzoni, @slava77, @lpernie can you please review it and eventually sign? Thanks. cms-bot commands are listed here |
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-1 Tested at: cdf802c You can see the results of the tests here: I found follow errors while testing this PR Failed tests: RelVals
The relvals timed out after 2 hours. runTheMatrix-results/4.22_RunCosmics2011A+RunCosmics2011A+RECOCOSD+ALCACOSD+SKIMCOSD+HARVESTDC/step2_RunCosmics2011A+RunCosmics2011A+RECOCOSD+ALCACOSD+SKIMCOSD+HARVESTDC.log136.7611 step2 runTheMatrix-results/136.7611_RunJetHT2016E_reminiaod+RunJetHT2016E_reminiaod+REMINIAOD_data2016_HIPM+HARVESTDR2_REMINIAOD_data2016_HIPM/step2_RunJetHT2016E_reminiaod+RunJetHT2016E_reminiaod+REMINIAOD_data2016_HIPM+HARVESTDR2_REMINIAOD_data2016_HIPM.log |
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Comparison not run due to runTheMatrix errors (RelVals and Igprof tests were also skipped) |
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please test |
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The tests are being triggered in jenkins. |
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Comparison job queued. |
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Comparison is ready @slava77 comparisons for the following workflows were not done due to missing matrix map:
Comparison Summary:
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| TH1F *h1PVz = (TH1F*) hPVx->ProjectionY("h1PVz", 0, -1, "e"); | ||
| //need to create a unique histogram name to avoid ROOT trying to re-use one | ||
| // also tell ROOT to hide its global state | ||
| TDirectory::TContext guard{nullptr}; |
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@Dr15Jones : mainly for my own education, could you please explain what this line is meant to? Thank you!
Also the class documentation in root doesn't look very explanatory to me:
https://root.cern.ch/doc/master/classTDirectory_1_1TContext.html
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This temporarily sets the global gDirectory pointer to nullptr which avoids accidental sharing across threads. When TDirectory::TContext is deleted, it rests gDirectory back to what it was before the constructor was called.
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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) |
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+1 |
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This change appears to have been insufficient. We are still seeing random crashes in the IB from the fits. |
The histogram returned from TH2F::Projection* may be the same one
as another thread if the name given is the same across the threads.
Using a unique name and using a TDirectory::TContext will prevent the
sharing across threads.