1. Clara Gaspar, March 2005 LHCb Online & the Conditions DB

2. Clara Gaspar, March 2005 2 LHCb Online Detector Channels Front End Electronics Readout Network Processing/Filtering Farm Storage Trigger Experiment Control System DAQ DCS Devices (HV, LV, GAS, Temperatures, etc.) External Systems(LHC,Technical Services,Safety,etc)

3. Clara Gaspar, March 2005 3 Online Usage of CondDB ❚ Two completely independent users: ❙ As Publisher ❘ The Experiment Control System Writes Online Conditions to the DB ❙ As Consumer ❘ The Event Filter Farm Algorithms Need Conditions for their processing/filtering tasks

4. Clara Gaspar, March 2005 4 Online Conditions Sources ❚ DCS ❙ High Voltages, temperatures, pressures, etc. ❚ DAQ & L0 Trigger ❙ Pedestals, thresholds, zero suppression parameters, gains, etc. ❙ DAQ & Trigger setup parameters ❚ EFF (Event Filter Farm) ❙ Pedestals, Thresholds, Gain Calibration, Alignment Constants, etc. ❙ Trigger setup parameters ❚ External Systems ❙ Accelerator data: energy, luminosity, average bunch currents, etc.

5. Clara Gaspar, March 2005 5 Online Conditions Publisher ❚ From the Control System point of view: ❙ Only output ❙ Only one interface: ❘ from the ECS i.e. PVSS ❙ Clients (offline algorithms) determine: ❘ Data organization 〡 Data format: XML (?) ❘ Data update rate 〡 Data could be stored in the Cond DB only if it changed by more than X or every hour 〡 independently of the PVSS read-out rate.

6. Clara Gaspar, March 2005 6 Conditions Data Types ❚ Raw Data Values read directly from hardware (ex.: HV readings, Temperatures, raw alignment data, etc.) ➨ No Versions, no Tags ❚ Processed Data Results of calculations done on raw data (ex.: calibration constants, alignment, etc.) ➨ Automatic Versioning, User Tags ➨ All Online data stored as "Raw Data"

7. Clara Gaspar, March 2005 7 Data Handling Architecture PVSS. To Offline... PVSS Cond.. DB Conf. DB To Offline... PVSS Arch. ❚ Three Logical Databases in the Online System Experimental Equipment

8. Clara Gaspar, March 2005 8 Online Database Contents ❙ Configuration DB contains: ❘ All data needed to configure the HW (or SW) for the various running modes 〡 Ex.: HV V0 Settings, Pedestal settings, trigger settings, etc. ❙ PVSS Archive contains: ❘ All monitoring data read from HW for monitoring and debugging of the Online System 〡 Ex.: HV Vmon Readings, pedestal readings, etc. ❙ Conditions DB contains: ❘ A subset of the monitoring data read from HW if it is needed for Offline processing 〡 Ex.: HV Vmon Readings if changed by more than n Volts ❘ Some configuration data once it has been used 〡 Ex.: Trigger settings used by a particular run

9. Clara Gaspar, March 2005 9 Dataflow Example Experimental Equipment PVSS. To Offline PVSS Cond.. DB Conf. DB To Offline PVSS Arch. Configuration settings for a running mode Monitoring data (at regular intervals) if Archive On if Passes Conditions filter if Needed for next run settings (Pedestal Followers)

10. Clara Gaspar, March 2005 10 Cond. DB Server ECS CondDB Architecture Control PC PVSS … ~100 Cond. DB Server. Cond.. DB ❚ Uses LCG: ❙ COOL ❙ RAL ❙ SEAL ❙ POOL ❙ BOOST ❙ etc. Conditions Data ❚ Define filters in PVSS: (per device type/device) ❙ Archive ❙ Condition: ❘ filter expressions

11. Clara Gaspar, March 2005 11 Event Filter Farm & CondDB Event Builder Switch SFC CPU...... SFC CPU...... SFC CPU......... ❚ CPUs run "Offline" Algorithms Online: ❙ Within Gaudi FW (interfaced to PVSS) ❙ Need Conditions: ❘ The Control PCs will get a snapshot of the CondDB (at Start of Run) and distribute to CPUs ❘ A few well-chosen Conditions can be updated while running

12. Clara Gaspar, March 2005 12 Control PC PVSS Dataflow Example Event Builder Switch SFC CPU...... SFC CPU...... SFC CPU......... Control PC PVSS Cond. DB Server Control PC PVSS Cond. DB Server. Cond.. DB Control PC PVSS ❚ Special filter for some conditions ❙ Trigger Farm Update At Run Start New Condition Update (t 0 +  t) Validity Start = t 0 +  t t0t0 CPU

13. Clara Gaspar, March 2005 13 Control PC PVSS Ex: The VeLo Alignment Cond. DB Server Control PC PVSS Cond. DB Server. Cond.. DB Event Builder Switch SFC CPU...... SFC CPU...... SFC CPU......... Control PC PVSS CPU Control PC PVSS

14. Clara Gaspar, March 2005 14 Online/Offline Synch Offline Cond DB Online Cond DB RichAl VeloAl RichAlOn VeloAlOn ❚ Synchronized by Oracle Tools RichAl VeloAl RichAlOn VeloAlOn