Establishing thresholds

Follow these steps to establish periodic exception thresholds.

About this task

Db2 provides a comprehensive set of thread activity and statistics fields. However, you usually need to define only a limited number of thresholds. Because long response times are a good indicator of a performance problem, you can start by defining exception thresholds for time fields. For example, you can set thresholds that are appropriate to your environment for class 1 and class 2 elapsed times.

  • Choose the most important applications or transactions in your system.
  • Always define exception thresholds for critical business applications. Applications that are frequently executed are good candidates for exception thresholds.
  • In a threshold set, specify thresholds for all Db2 counters that you want to monitor together.
Note: Periodic exceptions use WQAL (Db2 reads qualifications) to exclude DSCDBAT threads (disconnected database access threads, connid=disconn).

Procedure

  1. In the Exception Processing window, click Exception Processing > New Threshold Set.
  2. Select z/OS as operating system.
  3. Type a unique name for the set, your name (this is usually your logon user ID), and click OK.
  4. Add a threshold.
    1. Click Threshold Set > New Threshold.
    2. Under Exception field, select the counter you want to monitor, select the appropriate exception category and exception subcategory, and select the counter from the Select the exception field list.
    3. Under Warning and problem thresholds, specify the threshold values for warnings and problems for the selected counter.
    4. Under Qualifier, specify filter criteria for the counter.
    5. Click OK to save your settings.
  5. (Optional) You can perform one or more of the following optional steps:
    1. Add thresholds to the threshold set: Click Threshold Set > New Threshold.
    2. Change a threshold: Click the threshold and select Selected > Edit.
    3. Deactivate a threshold in a threshold set: Click the threshold and select Selected > Active.
  6. Click Threshold Set > Save.
    The Exception Processing window lists the new threshold set under the z/OS folder in the Threshold Sets folder.
  7. You can also:
    1. Change the properties of a threshold set: Click the threshold set in the folders pane of the Exception Processing window and select Selected > Properties.
    2. Add or remove thresholds from a threshold set: Click the threshold set in the folders pane of the Exception Processing window and select Selected > Edit.