revert "speedup SiStripClusterizer(FromRaw) using ThreeThresholdAlgorithm"

[slava77]

Reverts #47061
15_0_X variant of #47803

This reverts commit d288c81, reversing changes made to 6eea5fa.

copy-paste from #47803

---

#47061 (comment)

Following the TSG timing checks of the full unpacking/clustering showing possible slow down (initially reported late Jan/early Feb), I rechecked the impact and (unfortunately) confirm on data inputs (full menu based on /dev/CMSSW_14_2_0/GRun/V12 data from run 386593, 10K events, single thread test, in a configuration with mkFit and full strip unpacking and max cluster size set to 8):

• valgrind callgrind still shows a speed up of around 25%
• FastTimerService shows around 10% slowdown in hltSiStripRawToClustersFacility

I can speculate that callgrind is so slow that the underlying hardware memory access costs are mis-represented

I tried to measure the impact of individual contributions

• changes in template/inline of ThreeThresholdAlgorithm have almost negligible impact on timing
• precomputed qualityBits and rawNoises lead to most of the slowdown based on FastTimerService

The timing tests were done in CMSSW_14_2_1

@mmasciov
@elusian

---

@mmusich this should address #47803 (comment)

[cmsbuild]

A new Pull Request was created by @slava77 for CMSSW_15_0_X.

It involves the following packages:

• CalibFormats/SiStripObjects (alca)
• RecoLocalTracker/SiStripClusterizer (reconstruction)

@atpathak, @cmsbuild, @consuegs, @jfernan2, @mandrenguyen, @perrotta can you please review it and eventually sign? Thanks.
@GiacomoSguazzoni, @VinInn, @VourMa, @alesaggio, @echabert, @felicepantaleo, @gbenelli, @gpetruc, @jlidrych, @missirol, @mmusich, @mtosi, @robervalwalsh, @rovere, @rsreds, @threus, @tocheng, @yduhm, @yuanchao this is something you requested to watch as well.
@antoniovilela, @mandrenguyen, @rappoccio, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

• Backported from Revert "speedup SiStripClusterizer(FromRaw) using ThreeThresholdAlgorithm" #47803

[cmsbuild]

cms-bot internal usage

[slava77]

@cmsbuild please test

[mmusich]

backport of #47803

[cmsbuild]

+1

Size: This PR adds an extra 20KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-c890d4/45440/summary.html
COMMIT: 5e79aee
CMSSW: CMSSW_15_0_X_2025-04-08-1100/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/47810/45440/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 1 lines from the logs
• Reco comparison results: 238 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 4005338
• DQMHistoTests: Total failures: 4054
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4001264
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 49 files compared)
• Checked 218 log files, 189 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[perrotta]

+alca

• Master version of this PR succesfully merged since CMSSW_15_1_X_2025-04-08-2300

[jfernan2]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_15_0_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_15_1_X is complete. This pull request will now be reviewed by the release team before it's merged. @sextonkennedy, @rappoccio, @mandrenguyen, @antoniovilela (and backports should be raised in the release meeting by the corresponding L2)

[mandrenguyen]

+1