Author: Roderick, C.
Paper Title Page
MOPKN009 The CERN Accelerator Measurement Database: On the Road to Federation 102
 
  • C. Roderick, R. Billen, M. Gourber-Pace, N. Hoibian, M. Peryt
    CERN, Geneva, Switzerland
 
  The Measurement database, acting as short-term central persistence and front-end of the CERN accelerator Logging Service, receives billions of time-series data per day for 200,000+ signals. A variety of data acquisition systems on hundreds of front-end computers publish source data that eventually end up being logged in the Measurement database. As part of a federated approach to data management, information about source devices are defined in a Configuration database, whilst the signals to be logged are defined in the Measurement database. A mapping, which is often complex and subject to change and extension, is therefore required in order to subscribe to the source devices, and write the published data to the corresponding named signals. Since 2005, this mapping was done by means of dozens of XML files, which were manually maintained by multiple persons, resulting in a configuration that was error prone. In 2010 this configuration was improved, such that it becomes fully centralized in the Measurement database, reducing significantly the complexity and the number of actors in the process. Furthermore, logging processes immediately pick up modified configurations via JMS based notifications sent directly from the database, allowing targeted device subscription updates rather than a full process restart as was required previously. This paper will describe the architecture and the benefits of current implementation, as well as the next steps on the road to a fully federated solution.  
 
MOPMN027 The LHC Sequencer 300
 
  • R. Alemany-Fernandez, V. Baggiolini, R. Gorbonosov, D. Khasbulatov, M. Lamont, P. Le Roux, C. Roderick
    CERN, Geneva, Switzerland
 
  The Large Hadron Collider (LHC) at CERN is a highly complex system made of many different sub-systems whose operation implies the execution of many tasks with stringent constraints on the order and duration of the execution. To be able to operate such a system in the most efficient and reliable way the operators in the CERN control room use a high level control system: the LHC Sequencer. The LHC Sequencer system is composed of several components, including an Oracle database where operational sequences are configured, a core server that orchestrates the execution of the sequences, and two graphical user interfaces: one for sequence edition, and another for sequence execution. This paper describes the architecture of the LHC Sequencer system, and how the sequences are prepared and used for LHC operation.  
poster icon Poster MOPMN027 [2.163 MB]  
 
THCHAUST06 Instrumentation of the CERN Accelerator Logging Service: Ensuring Performance, Scalability, Maintenance and Diagnostics 1232
 
  • C. Roderick, R. Billen, D.D. Teixeira
    CERN, Geneva, Switzerland
 
  The CERN accelerator Logging Service currently holds more than 90 terabytes of data online, and processes approximately 450 gigabytes per day, via hundreds of data loading processes and data extraction requests. This service is mission-critical for day-to-day operations, especially with respect to the tracking of live data from the LHC beam and equipment. In order to effectively manage any service, the service provider's goals should include knowing how the underlying systems are being used, in terms of: "Who is doing what, from where, using which applications and methods, and how long each action takes". Armed with such information, it is then possible to: analyze and tune system performance over time; plan for scalability ahead of time; assess the impact of maintenance operations and infrastructure upgrades; diagnose past, on-going, or re-occurring problems. The Logging Service is based on Oracle DBMS and Application Servers, and Java technology, and is comprised of several layered and multi-tiered systems. These systems have all been heavily instrumented to capture data about system usage, using technologies such as JMX. The success of the Logging Service and its proven ability to cope with ever growing demands can be directly linked to the instrumentation in place. This paper describes the instrumentation that has been developed, and demonstrates how the instrumentation data is used to achieve the goals outlined above.  
slides icon Slides THCHAUST06 [5.459 MB]