Analyzing optimization exceptions for index databases
Analyze the optimization exceptions that were detected for index databases.
Before you begin
Ensure that you can access the Sensor Data Statistics report that contains the latest sensor data. If you cannot access this report, run the FF DB Sensor Printing utility to generate the report.
About this task
If a secondary index database has an overflow data set defined, duplicated index pointer segments are located in the overflow data set. Accessing the index pointer segments in the overflow data set requires extra I/O operations. Consequently, when an excessive number of index pointer segments exist in the overflow data set, the condition might cause performance degradation.
Optimizing secondary index databases typically includes tuning the database definitions to decrease the number of index pointer segments in the overflow data set.
In this task, you will identify the number of index pointer segments in the overflow data set, and determine whether you can reduce these segments.
For HIDAM primary indexes, HALDB partitioned secondary indexes, and secondary index databases without an overflow data set, you do not need to analyze duplicated keys.
Procedure
- Exception class name: NUMBER_OF_INDEX_POINTER_SEGMENTS
- This exception indicates that the number of index pointer segments (IPS) is high.
- Exception class name: EXCESSIVE_INDEX_OVERFLOW
- This exception indicates that many index keys are duplicated. This exception is reported for secondary indexes that have an overflow data set.
What to do next
If the only exceptions that you received are optimization exceptions, continue with Resolving optimization exceptions for index databases.