Application Environment Load Balancing Job and Queue Management

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Application EnvironmentLoad BalancingJob and
Queue Management

• Tim Smith CERN/IT

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Application Environment

• Uniform environment variables
• HEPiX scripts initialise user environment
  identically interactive and batch
• Uniform file access
• Home directories are AFS
• Uniform tool access
• SUE / ASIS to make all same tools available in
  same places on all architectures
• Uniform library access
• Mainly shared file systems, some local instl

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Load Balancing

• Interactive
• ISS
• 2 central servers - run probe metrics cluster
  clients
• Choose least loaded and update DNS servers
• lxplus.cern.ch gtgt lxplus.plus.cern.ch
• Batch
• LSF multi-clusters
• Interactive submission cluster
• Batch execution cluster
• Multiple user communities chaotic and production
  usage