HLTPFlow trk extrapolation: Loosening tolerance setting
Purpose
Loosening tolerance of STEP propagator used in the track extrapolation to calorimeter for PFlow reconstruction in the HLT in order to reduce CPU at the HLT (ATR-27539). Track extrapolation CPU vs performance optimisation was studied by @otheiner for his QT ATR-22226 (following suggestions in official ATR-21636 JIRA for HLT pflow optimisations general). The new setting was validated in HLT Reprocessing ATR-27324 where a 25% CPU reduction for HLTPFTrackExtension_ftf
alone is measured with very minute changes to physics distributions (see discussions in JIRA and Ondrej's summary slides). It does affect trigger counts for a number of chains, but mostly by less than 1%. Impact should be on the trigger turn-ons only from slightly different reconstructed jet momenta - verified for some chains. HLT reprocessing was signed off by jet, met and b-jet.
Changes
- Changing default tolerance of
Trigger.Jet.PFlowTolerance
ConfigFlag from 10-4 to 10-2 (one line change). Deciding to keep ConfigFlag for now (as opposed to hardcoding in python), in case of issues and as we could consider testing a further loosened tolerance. - Updating trigger count reference files.
Affects...
- reduced CPU usage at HLT
- Small change in physics - expected to be on trigger turn-ons from slightly different reconstructed jet momenta.
- reference trigger counts
tagging @otheiner @miochoa @xingguo @lbeemste @lshi @jwuerzin @sidoti @sshaw @tamartin
Merge request reports
Activity
CI Result SUCCESS (hash f84108ae) Athena AthAnalysis externals cmake make tests Full details available on this CI monitor view. Check the JIRA CI status board for known problems
Athena: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 71985] added review-approved label and removed review-pending-level-1 label
added review-approved-tier0 label
added review-approved-point1 label
mentioned in commit 33836590
mentioned in merge request !63344 (merged)