Understanding User Activity Detection

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User activity detection settings can be configured in a workstation node and unmanaged server node template to restrict the nodes that are brought online during a scheduled online time block, or to stop jobs that are running on those nodes during a scheduled period. For example, these settings can help ensure that HPC jobs do not interfere with a user’s work on a workstation during a scheduled online time block.

You can elect to make a workstation node or an unmanaged server node available to run jobs if either or both of the following conditions are detected:

  • No keyboard or mouse input is detected within a specified time interval

  • CPU usage is below a specified level, for a specified period of time

Note

  • User activity detection settings in the node availability policy are supported starting in HPC Pack 2008 R2 with Service Pack 1 (SP1). Use of at least HPC Pack 2008 R2 with SP2 is recommended for these settings.
  • Both workstation nodes and unmanaged server nodes are supported starting in HPC Pack 2008 R2 with SP3. Only workstation nodes are supported in earlier versions of HPC Pack 2008 R2.

Additional considerations

The following points relate to workstation nodes and unmanaged server nodes that have been deployed using a node template in which user activity detection settings are configured:

  • User activity detection settings are ignored on any nodes where HPC Pack 2008 R2 is installed and has not been upgraded to at least SP1.

  • If user activity detection settings are configured, an HPC job will run with BelowNormal priority on the nodes. This ensures that the HPC tasks will not take priority over other normal processes on the nodes. Additionally, HPC jobs are automatically stopped on the nodes when keyboard or mouse input is detected. This means that HPC tasks will relinquish the system quickly when users log on to their workstations.

  • Nodes that are not running jobs during an online time block because the CPU usage is above the specified level will automatically become available if the CPU usage drops below the specified level for a specified period of time.

  • Any HPC jobs are stopped automatically when the CPU usage for non-HPC work rises above the specified level, or keyboard or mouse activity is detected. This helps ensure that HPC jobs will not interfere with scheduled tasks on the nodes.

  • An administrator can reduce the priority of scheduled tasks on the nodes (using tools in the operating system) so that they do not cause a running HPC job to stop. For example, to ensure that a subsequent scheduled task on a node cannot interfere with an HPC job, the administrator can configure the scheduled tasks in the operating system to run with a priority below BelowNormal.

See Also

Understanding the Workstation Node and Unmanaged Server Node Availability Policy