Outline
         • History
         • Design
         • First prototype
         • DataGrid fabric mgmt monitoring task
         • Conclusions
         May 24 2001                PEM status report. LCCWS@FNAL O                          2
                                    .Bärring
                       History
      • The Performance and Exception Monitoring 
        (PEM) project is a CERN IT project since 1999
         – Leader: Tim Smith, Bernd Panzer-Steindel from 2001
         – Goal (and innovation): Monitor and alarm on service 
           rather than server
      • Long requirement phase with input from many IT 
        groups
      • Design settled in mid-2000
      May 24 2001     PEM status report. LCCWS@FNAL O   3
                      .Bärring
                                             Design
                              1..n     1                      1..n     1
                                                                                 Measurement               1
                  Agent                         Broker                           repository (MR)
                                                    1..n                                1
     sensors      actuators                           1
                                                                    1    1..n
                                          Configuration                           Correlation
                                         Repository (CR)                         Engine (CE)
                                                          1
                               1..n    1                     1..n
              User Interface               Access control
                                                                                             Data
                                                                                             Control
           May 24 2001                     PEM status report. LCCWS@FNAL O                                    4
                                           .Bärring
                    Design: agent
      • The agent forwards data from monitoring 
         sensors to the broker
          – Buffering of data for transfer efficiency and 
            fault tolerance
          – The configuration of local sensors and actuators 
            is received via the broker
          – Firing of actuators is triggered by MR (or CE) 
            via broker to the agent
      May 24 2001       PEM status report. LCCWS@FNAL O       5
                        .Bärring
                    Design: broker
      • The broker was introduced for scalability
          – Transmitter of configuration information to
             • Agents
             • Measurement repository
          – Transmitter of measurement data from agent to 
            measurement repository
          – Transmitter of requests for firing actuators from 
            MR to the agents
      May 24 2001        PEM status report. LCCWS@FNAL O       6
                         .Bärring