Monitoring processing elements

Use the Streams Console or streamtool commands to view the status of processing elements (PEs) in a Teracloud® Streams instance.

About this task

You can only view PE information that you are authorized to work with, as determined by the access control lists for Teracloud® Streams.

Procedure

  • Monitor processing elements in the Streams Console.
  • Run one or more of the following commands:
    • The streamtool lspes command provides a health summary for each PE.
    • The streamtool displaype command displays details about a specific PE, including the configuration settings that are used by the PE.
    • The streamtool capturestate command provides more detailed information about the system health.
    For more information about command syntax and options, enter streamtool man command-name.

Results

The command and Streams Console output includes status information and a health summary for each PE. If a PE is running and all of its required and optional connections to other PEs are currently connected, Teracloud® Streams reports that the PE is healthy.

PEs have state and reason code (RC) values that provide information about the status of the PE. These are detailed in the tables below.

Table 1. Processing element states
PE state Description
Constructed The PE is initializing.
Restarting The PE is restarting.
Running The PE is running.
Starting The PE is starting.
Stopped The PE is stopped.
Stopping The PE is stopping.
Unknown The domain controller service cannot be contacted to determine the current state of the PE.
Table 2. Processing element reason codes
Reason code Description
(-) None No reason code is available.
(A) Automatic The system automatically moved the PE to this state.
(C) Crashed PE processing stopped unexpectedly with a signal condition such as a segmentation violation (SEGV).
(F) Failure The PE processing completed, but it returned a completion code that indicates that a failure occurred.
(H) Host failure The PE is transitioning to a new resource because the resource it was running on experienced a failure. The domain controller service that is associated with the resource was removed or restarted.
(N) No feasible resource The application manager service cannot find a resource to run the PE.
(R) User request There was a user request to move the PE to this state, for example, stopping the PE because of a job cancellation request.
(S) Set capabilities failure The domain controller service cannot set the requested authority for the PE.
(V) Voluntary The PE stopped because its processing completed successfully without any errors.

Example

For examples of the streamtool command output, see the appropriate command reference topics.