Maria del Carmen Barandela Pazos CERN CHEP 2-7 Sep 2007 Victoria LHCb Online Interface to the Conditions Database

Maria del Carmen Barandela PazosCHEP 2007, Victoria OUTLINE ● Conditions, Conditions DB & LHCb Online ● LHCb Online Interface to the CONDB ○ System components ○ Data flow ● Summary - 1 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria CONDITIONS ● Non-event detector data that vary with time TIME DATA ITEM VERSION ● Condition Object: - Metadata - Payload Data item identifier Interval of Validity: [since, until] Version information Actual data variables: temperatures, calibration parameters, etc.

Maria del Carmen Barandela PazosCHEP 2007, Victoria CONDITIONS DB FOLDER SETS FOLDERS IOVs OBJECT DATA Hierarchical organization & Versioning Interval of Validity access & Versioning Data payload - 3 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria ONLINE CONDB 2 Experimental Equipment PVSS Online Offline Online Offline - Subset of monitoring data from HW - Online Usage Publisher: control system Consumer: trigger processes LHCb pit CERN - 4 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria INTERFACE TO CONDB 2 ● Store data produced in the LHCb pit ● System components - Communication layer - PVSS panel - PVSS control scrip SCADA( Supervisory Control and Data Acquisition ) Developed by ETM Software package for control and visualization - Conditions database server: COOL API for reading and writing conditions data Developed by LCG group at CERN Management condition data in the LHC experiment DIM (Distributed Information Management ) system Developed at CERN Machine independent inter-process communications - 5 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria PVSS PANEL 2 ● Display existing nodes in the CONDB ● Define conditions ● LHCb framework component ● Select parameters & update type ● Condition update type - Time - Change value - Value + or – value or % - Opt. Combination ● Server status & error msn ● Visualization XML - 6 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria PVSS CTRL SCRIPT 2 ● Creates 1 thread per condition ● Gets the existing definitions stored as dpe. ● When is the right moment : - Builds the XML string ● Independent from the panel - Gets automatically new condition definitions -Sents the condition to the server dpe CTRL SCRIPT XML dpe - 7 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria CONDB SERVER 2 ● Receives the conditions as DIM command ● Publishes the CONDB nodes as DIM service ● Generic implementation COOLDifferent relational backends SQLITE & Oracle - 8 -

Maria del Carmen Barandela PazosCHEP 2007, Victoria DATA FLOW PVSS DNS DIM Name Server CONDB SERVER Online CONDDB 1. Get conditions info 3. Request conditions service 4. Service info 5. Condition Service info 6. Command: updated condition 7. Insert the updated condition 2. Register services

Maria del Carmen Barandela PazosCHEP 2007, Victoria SUMARY ● Simple and flexible way to define conditions ● System fully functional (still being tested by users) ● Generic implementation of the server

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