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Hopper User Environment Monitoring

NERSC is monitoring the user experience on Hopper via login node No 1. The chart below shows a history of the time required to perform three simple interactive tasks on the hopper01 login node. The monitoring allows NERSC to quantitatively measure the user environment experience and take action when needed. It also shows users the behaviors of different files systems and computers (Edison and Carver coming soon) for everyday computing tasks. The results help ensure NERSC provisions system with adequate interactive resources to support usage patterns.

Differences in execution time could be caused by file system issues and/or login node load (as well as other less frequent problems).

The three tasks:

  • Compile and link a small code (2 source files, 139 lines total). Note the difference building in different file systems.
  • Create 500 small files in a directly.
  • Perform a long recursive listing of a directory tree containing 520 directories and about 12,000 files.