HLT Jet / MET Status 2012 / Plans 2013
K. Johns, V. KaushikUniversity of ArizonaR. Piegaia, H. Reisin
Buenos Aires UniversityTrigger Monitoring: Review
Nov 30, 2012
Shifter / Expert Tools• What have been the tools most used by shifter and experts
Online Shifters use mainly DQMD / OHP
Offline Used more extensively by shifters and experts Provides a larger (better) picture by
– Monitoring different calorimeter components which is very useful to track problems with sub-detectors (Tile, LAr, Preshower HEC, EMEC etc.)
– Monitoring different chains (low pt, high pt)– Correlation between L1, L2, EF proved to be useful
• Shifter instructions / logbook / useful ROOT-macros Macros to compare histograms from reprocessing to spot
differences, twiki’s proved to be very useful for logging
04/22/23 Venkat 2
Monitoring Strategy• What have been the typical problems found by the monitoring?
(See next two slides for examples)• What have been the successful strategies?
• Strategy for both HLT Jet/MET slices have been to Provide numerous diagnostic plots (expert category) Select a few salient ones to display (for shifter) Provide documentation and have on-call experts provide
feedback on runs/defects and reprocessings https://twiki.cern.ch/twiki/bin/viewauth/Atlas/AtlasJetMetOnCa
llExpert2012 https://twiki.cern.ch/twiki/bin/viewauth/Atlas/JetMetExpertshi
ftInstructions
04/22/23 Venkat 3
Example: Offline MET
04/22/23 Venkat 4
Eta/Phi maps vs 1d histograms of MET components used by experts to diagnose problems with calorimeter (hot-spots in this case)
Example: Offline Jet
04/22/23 Venkat 5
• Spike in L1_j165 also seen in L2_j165 and also in a different chain EF_j220 which indicates a calorimeter issue. This was cross checked with MET which also indicates a problem at eta = 2.45
• Jet / MET slices monitoring histograms used in conjunction to identify calorimeter noise
Problems in 2012• Problems detected by HLT Jet/MET
Calorimeter issues dominantly Unclear if we would always catch a subtle HLT Jet/MET problem from DQ
(see below) because nearly every problem was calorimeter-related Comparing histograms during reprocessing to identify changes from
original Issues with the menu (chain name changes)
Trigger name change resulted in empty histograms with EF_j35 Problem was identified as being a name issue with a resulting low rate
being sent to express_express and hence empty histograms!
04/22/23 Venkat 6
EMPTY HISTOGRAMS ARE SOMETIMES USEFUL TO DETECT PROBLEMS!
Problems in 2012• Problems undetected by HLT Jet/MET
Issues related with trigger rates Issues related to trigger efficiency drop / fluctuations Reason
express_express uses only a small fraction of events with ~0.4 Hz for monitored chains
Not very many events to make efficiency plots / turn-on curves and monitor them
04/22/23 Venkat 7
Menu Dependence• What (if any) dependence of the DQ checks is there on Trigger
Menus?
Online XML configuration needs to be changed with change in menu – which
invariably results in change in trigger chain names – both for HLT Jet and HLT MET
Offline Most checks (Jet/MET slices) don’t depend on trigger menu However - the menu changes affect the trigger chain names which can
cause issues with HLTJet monitoring– Coding the changed names (mostly TrigXXXMonitoring/python)– Asking for new monitoring tag at Tier0– Making changes to (han) web display configuration– Use of reg-exp expressions suggested but unclear if it would help
04/22/23 Venkat 8
Tools of Trade / How to Improve• Offline
Monitoring Algorithms (ManagedMonitorToolBase) We are happy with the Athena side of things in general and specifically
the HLTMonBase which has been very useful for all slices Some complaints about the number of folders/pages (triggers) that had
to be opened – perhaps add additional overview pages DataQualityUtils/DataQualityConfigurations
This is where code needs improvements There is no easy solution to merging / post-processing algorithms which
use histograms (via their names and path in ROOT file) to access them. Name changes in upstream (Athena) can cause delays in updating the above to reflect the changes
Web display: all_in_dir { } is useful but han needs to be designed in a smarter way to accommodate reg-exp patterns on monitored quantities
04/22/23 Venkat 9
Tools of Trade / How to Improve• Reference Histograms
Add run number/date of reference histogram Possible to choose reference histogram as a function of
luminosity at run start?• History Tool
Very useful for detectors (Muon, Calorimeter, ID) Not particularly used by HLT
• Online histogram viewing Very useful with new features to zoom into axes using dynamic
ranges• Preseries
This was useful to test online changes. Thanks to Barbara Gonzalez et al. for such nice (working) cookbook instructions.
04/22/23 Venkat 10
Tools of Trade / How to Improve• HLT Jet and MET meetings
Difficult for us (U.Arizona) to make because of other meeting conflicts
Hope to expand the DQ group to include an on-site collaborator to get feedback from meetings
Reports posted on twiki by DQ shifters very useful and informative for us (U. Arizona)
• Documentation The few shifters we talked to thought it was adequate One suggestion was to have a better response sheet for the on-
call shifter especially since many of the issues were calorimeter related
04/22/23 Venkat 11
Plans for 2013 - 15• Both HLT Jet and MET plan extensive changes in architecture and
algorithms for post-LS0 running Increasing trigger rates and pileup must be addressed Try to migrate/integrate offline to online More detailed task lists exist from HLT Jet and MET conveners
6-7 FTE’s needed for each group DQ monitoring will have to stay informed and respond to these
changes Challenging because monitoring always comes “last” so there is a shorter
response time
• Possible to merge HLT Jet and MET with Calo Trig monitoring given the overlap in issues?
04/22/23 Venkat 12
HLT Jet / MET
04/22/23 Venkat 13
The goal of next Friday is twice:
- to get an overview about the running of 2012 + what have been the tools (online and offline) most used (by shifter and experts), + what have been the successful strategies, + what have been the typical problems found by the monitoring, + are there problems not been seen, + dependence on Trigger Menus of the DQ checks, + general impression about usability, reliability, comfort in handling and updates
- to get an overview what needs to be done for 2013 + plans for updates --> online software in TrigSteer and Trigger Algorithms --> offline software in TrigHLTMon --> DQ interfaces online (DQMD/OHP) and offline (han) + potentials for merging with other slices + manpower situation and time planing during the shutdown for updates and commissioning
Top Related