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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Effect of configuration on CPU utilizationThe combination of operating-system and HCL OneDB™ configuration parameters can affect CPU utilization. You can change the settings of the HCL OneDB™ configuration parameters that directly affect CPU utilization, and you can adjust the settings for different types of workloads.
Configuration parameters and environment variables that affect CPU utilizationSome configuration parameters and environment variables affect CPU utilization. You might need to adjust the settings of these parameters and variables when you consider methods of improving performance.
Specifying virtual processor class informationUse the VPCLASS configuration parameter to specify a class of virtual processors, the number of virtual processors that the database server should start for a specific class, and the maximum number allowed.

Specifying virtual processor class information

Use the VPCLASS configuration parameter to specify a class of virtual processors, the number of virtual processors that the database server should start for a specific class, and the maximum number allowed.

To execute user-defined routines (UDRs), you can define a new class of virtual processors to isolate UDR execution from other transactions that execute on the CPU virtual processors. Typically you write user-defined routines to support user-defined data types.

If you do not want a user-defined routine to affect the normal processing of user queries in the CPU class, you can use the CREATE FUNCTION statement to assign the routine to a user-defined class of virtual processors. The class name that you specify in the VPCLASS configuration parameter must match the name specified in the CLASS modifier of the CREATE FUNCTION statement.

For guidelines, on using the cpu and num options of the VPCLASS configuration parameter, see Setting the number of CPU VPs.