1. Moritz Backes, Clemencia Mora-Herrera Département de Physique Nucléaire et Corpusculaire, Université de Genève ATLAS Reconstruction Meeting 8 June 2010 Summary of Recent Trigger Changes Affecting Tier0

2. Trigger Updates Affecting Tier0 Trigger monitoring packages: Frequent updates & improvements, bugfixes, additional histograms & checks  Obviously important for trigger operations  Pure monitoring, no impact on EDM schema nor physics output  Nonetheless all these updates are always carefully tested by running full reconstruction on cosmics / MC / collision BS files to ensure absence of ERRORs or related WARNINGs before submission. Trigger ntuple production at Tier0: Occasional bugfixes, updates & additions  Important for commissioning and fast validation/feedback for the trigger  Again no impact on EDM / physics output  Again comprehensive reconstruction tests are performed before submission to AtlasProduction ‘Transparent’ EDM changes: Occasional necessity of trigger updates that affect the ESD/AOD content  ‘Transparent’: EDM updates do not change the physics output nor break forward / backward compatibility and thus have no impact on physics analyses.  Changes are carefully coordinated & tested by trigger EDM experts  Once a set of tags is established, the changes are tested by running the full reconstruction on cosmics / MC / collision BS files to ensure absence of ERRORs or related WARNINGs  The resulting ESD/AOD pool files are checked for differences 8/06/10Moritz Backes, Clemencia Mora2

3. Recent ‘transparent’ trigger EDM updates Recent bundle submitted to AtlasProduction 15.6.10.Y: TrigT1CaloByteStream-00-08-05 Trigger/TrigT1/TrigT1CaloByteStream TrigEDMConfig-00-00-20-03 Trigger/TriggerCommon/TrigEDMConfig TriggerJobOpts-00-03-20 Trigger/TriggerCommon/TriggerJobOpts RecExPers-00-02-63 Reconstruction/RecExample/RecExPers TrigSerializeTP-00-01-07 Trigger/TrigDataAccess/TrigSerializeTP Differences in pool files are as expected: -------------------------------------------------------------------------------- ## ERROR: files don't have the same content !! ## collections in 'chk' and not in 'ref’ + Rec::TrackParticleContainer_tlp1_HLT_InDetTrigParticleCreation_minBias_EFID + TriggerTowerCollection_tlp1_TriggerTowersMuon ## collections in 'ref' and not in 'chk’ -TrigOperationalInfoCollection_tlp1_HLT_EXPRESS_OPI_EF ================================================================================ ::: comparing common content (mem-size)... [ERR] 26.395 kb (ref) ==> 26.439 kb (chk) | EventStreamInfo_p2_StreamESD [ERR] 3087.343 kb (ref) ==> 3116.640 kb (chk) | HLT::HLTResult_p1_HLTResult_EF [ERR] 14956.997 kb (ref) ==> 14967.251 kb (chk) | POOLContainer_DataHeaderForm ================================================================================ 8/06/10Moritz Backes, Clemencia Mora3

4. Changes included in recent EDM bundle (1) 1)Changing the version of the persistent class of TauDetailsContainer from tlp1 to tlp2: Updating the transient-to-persistent converter class used by the trigger serializer for writing out TauDetailsContainer objects from versions tlp1 to tlp2 in order to catch up with the offline change. First step in tackling some floating point exceptions (bug #65082 – still ongoing) and thus to increase overall robustness.  No consequences for offline analyses 2)Removal of TrigOperationalInfoCollection#HLT_EXPRESS_OPI_EF from ESD, except for express stream reconstruction Recently introduced monitoring quantity that contains lists of chains which have express stream tags Histograms only need to be written to express stream and were never intended for standard reconstruction They have no use for physics analyses  dropped from ESD/AODs to avoid confusion.  No consequences for offline analyses 8/06/10Moritz Backes, Clemencia Mora4

5. Changes included in recent EDM bundle (2) 3)Adding a new key for MinBias TrackParticles (Rec::TrackParticleContainer_tlp1_HLT_ InDetTrigParticleCreation_minBias_EFID) in ESD/AOD This change is necessary to check the performance of EF MinBias tracks w.r.t. offline tracks. Since EF uses a different selection these tracks are not available anywhere else. The size increase is small (order 0.1 kb / event)  Additional quantity in ESD/AOD thus no consequences for offline analyses. 4)Additional LVL1 key adding trigger tower objects to ESDs only (TriggerTowerCollection_tlp1_ TriggerTowersMuon) for L1 monitoring Additional TriggerTowerCollection containing 128 towers but reduced number of readout timeslices in original TriggerTowerCollection so small overall size increase. This information is needed to investigate how tile muon signals can contribute to clean up the cavern background in the RPC triggers.  No consequences for offline analyses 8/06/10Moritz Backes, Clemencia Mora5

6. Other changes to be deployed soon Update of the MuonFeatureDetails TP converter from _tlp1 to _p2 Brings a performance change that results in smaller ESD / AOD sizes and optimized CPU usage. Still validating in devval after solving savannah bugs #68000, #68455 We will start to check with AtlasProduction once it is safely running and well tested. 8/06/10Moritz Backes, Clemencia Mora6

7. Possible Updates from the Tau Slice Tau combined performance group are studying the use of additional variables to handle pile up: Suggestion up-to-date: –Introduce 6 additional variables built out of topo clusters attached to tauJets, which are supposed to give good performance in case of pile-up –Currently tau people are trying to converge on an optimized selection for these variables between offline and trigger More information can be found in a dedicated discussion on the sharepoint of the tau combined performance group: –https://espace.cern.ch/atlas-perf-tau/Selection/Lists/General%20Discussions/Flat.aspx?RootFolder=%2fatlas- perf- tau%2fSelection%2fLists%2fGeneral%20Discussions%2fEffects%20of%20pileup%20on%20TauID&FolderCT ID=0x01200200DB9E9CBE9C190841BFFB578FE2AEE66F&TopicsView=https%3A%2F%2Fespace.cern.ch %2Fatlas-perf-tau%2FSelection%2Fdefault.aspx These changes are at an early stage of development – no decisions have been made. Trigger will announce & discuss such changes well in advance when they become necessary and ensure that all requirements and guidelines are met and well tested. 8/06/10Moritz Backes, Clemencia Mora7

8. Summary & Remarks Summary: Recently a few EDM updates have been requested by the trigger community for Tier0. The EDM updates are ‘transparent’ meaning they do not break backwards / forwards compatibility nor affect offline analyses. Some questions & remarks: Occasional transparent trigger EDM updates will continue to be necessary from time to time for debugging purposes etc. All quantities related to physics analyses will remain unchanged. Concerning forward compatibility we would like to know what procedure you recommend for tests and against which reference release you would like to remain compatible. In particular concerning the addition of single data members: Have tests been performed by the reconstruction group yet and can you recommend a clear procedure for such an EDM evolution. We would like to know from the combined performance groups if there are any HLT-related changes foreseen to deal with pileup and if these involve trigger EDM updates. Could the standard reconstruction tests (q120 / q122) be provided with up-to-date cosmics & collisions files. This avoids unnecessary ERRORs and WARNINGs and allows to discover potential problems. 8/06/10Moritz Backes, Clemencia Mora8