Selecting a server instrumentation strategy

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Follow the usage strategies to get the best results when you use server instrumentation.

Procedure

You can select any of the following server instrumentation strategies:

  • Start and stop server instrumentation around the operation. An operation can be any procedure that affects performance, such as backup or restore operations.
    1. Start server instrumentation, and start the operation that you want to monitor.
    2. End server instrumentation immediately after the operation completes. If a thread is started when instrumentation is active, session and process statistics are included in the output. A thread is a sequence of actions that are managed by an operating system scheduler. A process might require more than one thread. For example, a backup operation uses at least two threads. You can issue an IBM Storage Protect administrative client macro command to start server instrumentation before you start the operation.
  • Set a time limit when you run server instrumentation.
    • The optimum length of time to run server instrumentation for most cases is 5 - 15 minutes. You can run server instrumentation for up to 30 minutes.
    • If server instrumentation is active for 30 minutes, hundreds of threads are traced and the output can be overwhelming. Reports with that many threads can make it more difficult to diagnose a problem.
    • Do not run server instrumentation on a busy server for the maximum amount of time. When possible, limit instrumentation on the server. If the system workload is the problem, instrumentation results might not help you resolve the source of system performance problems.
  • Find a match for the multiple threads of a particular session or process. Look for the parent and child relationships between the threads. In the instrumentation output per thread, use the thread ID and the parent thread ID to find the other threads that are associated with the operation.
    • Find the thread in the instrumentation data. For example, look in the IBM Storage Protect activity log file for a session ID that matches a particular client session in the instrumentation data.
    • During the operation, take the output from the SHOW THREADS command to see the session or process ID that a particular thread is working on. Use the thread ID from the output to find that same thread ID in the instrumentation.
    • Look for related threads, which are based on the amount of data that is moved.