Rendering problems of BeamMonitor fitted plots

[micsucmed]

After deploying PR #1269 during beams, d0 vs phi0 and track zo plots are blacklisted again. We have cleared the blacklist, and restarted our playback DQM GUI server (srv-c2f11-29-03). We recorded the log's right after the restart that might provide more information, they can be found here.

[syuvivida]

Hello, just to add that the author of PR #1269 could see the d0 vs phi0 and track z0 plots displayed without problems in his own private DQM GUI. Both plots require a fit and call TF1. Please advise how we could debug this issue. Thanks!!

[francescobrivio]

Just to add some details:

• the d0 vs phi0 and track z0 plots were ok in the past (Run 2) IIRC (@mmusich can confirm)
• since Run 3 they are blacklisted in Production and Playback DQM instances
  • Let me add that sometimes they are visible (but this seems pretty random)
• In local instances of the DQM GUI (see e.g. my PR Update BeamSpot shifter plots #1269) they are displayed properly (and also when one opens the dqm root files directly with a TBrowser)

Since i'm not able to reproduce locally the error reported above by @micsucmed above

Error in <TBufferFile::ReadClassBuffer>: Could not find the StreamerInfo for version 12 of the class TF1, object skipped at offset 1135
Error in <TBufferFile::CheckByteCount>: object of class TF1 read too few bytes: 2 instead of 1205

I'm really not sure how to debug this.

Cheers,
Francesco for the BeamSpot team

[dzuolo]

Dear colleagues,
I would like to report that a miracle happened and since yesterday, or at least I have seen this yesterday, the BeamMonitor and BeamMonitorHLT plots with a fit superimposed are now visible!!!
I attach a screenshot.
Does anybody in DQM core team have an explanation for this or should we simply call it a miracle?
cheers,
Davide