Matti Kortelainen

An earlier discussion in https://mattermost.web.cern.ch/cms-o-and-c/pl/om99iu1dmfrdjf855beum7387w suggested that given the multiple output modules one could see improvement with 2 (or even 3) threads. I think it would be useful to investigate...

> There are lots of stalls - eg, Here it spent 2 hours.. > Begin processing the 2712th record. Run 356993, Event 2537640, LumiSection 145 on stream 0 at 08-Aug-2022...

Just to check some of our assumptions, I ran the repack job with the first streamer file copied locally with IgProf (in this setup I got throughput of 4.2 events/s...

I continued with the first-lumi job, and got * with 1 thread: 4.35 events/s throughput, >99 % efficient * with 2 threads: 4.89 events/s throughput, 53 % efficient The job...

I made a histogram of the time differences between subsequent `Begin processing` printouts from the log of the original job (notice logarithmic y axis)  and some quantile numbers *...

It turns out that the example job is using `lazy-download` via ```py process.SiteLocalConfigService = cms.Service("SiteLocalConfigService", overrideSourceCacheHintDir = cms.untracked.string('lazy-download') ) ``` and the `XrdFile` gets 128 MB read requests that it...

Can the comment in https://github.com/cms-sw/cmssw/blob/47dded9ac5760e86d4ce6aaa18189f10765ef303/DQM/GEM/python/gemEfficiencyAnalyzer_cff.py#L9-L10 be interpreted that the name worked in 12_2_0 but not in 12_3_0? One big difference between 12_2_0 and 12_3_0 is ROOT, 6.22 vs. 6.24.

I see the `SimpleCandidateFlatTableProducer` uses https://github.com/cms-sw/cmssw/blob/a1ee449d0c95cbe0ce77e39a3ba396879d0437a4/PhysicsTools/NanoAOD/interface/SimpleFlatTableProducer.h#L170-L171 uses `StringObjectFunction` and `StringCutObjectSelector` that use ROOT underneath.

@mariadalfonso Could you provide a recipe to reproduce? I tried with the unit test https://github.com/cms-sw/cmssw/blob/master/CommonTools/Utils/test/testCutParser.cc with ```diff @@ -73,9 +73,9 @@ void testCutParser::checkHit(const std::string &cut, bool res, const SiStripRecH void...

Tests were added in https://github.com/cms-sw/cmssw/pull/38856 that was merged in CMSSW_12_5_X_2022-08-02-2300