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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.
Setting the MULTIPROCESSOR configuration parameter when using multiple CPU VPsIf you are running multiple CPU VPs, set the MULTIPROCESSOR configuration parameter to 1. When you set MULTIPROCESSOR to 1, the database server performs locking in a manner that is appropriate for a multiprocessor. Otherwise, set this parameter to 0.

Setting the MULTIPROCESSOR configuration parameter when using multiple CPU VPs

If you are running multiple CPU VPs, set the MULTIPROCESSOR configuration parameter to 1. When you set MULTIPROCESSOR to 1, the database server performs locking in a manner that is appropriate for a multiprocessor. Otherwise, set this parameter to 0.

The number of CPU VPs is used as a factor in determining the number of scan threads for a query. Queries perform best when the number of scan threads is a multiple (or factor) of the number of CPU VPs. Adding or removing a CPU VP can improve performance for a large query because it produces an equal distribution of scan threads among CPU VPs. For instance, if you have 6 CPU VPs and scan 10 table fragments, you might see a faster response time if you reduce the number of CPU VPs to 5, which divides evenly into 10. You can use onstat -g ath to monitor the number of scan threads per CPU VP or use onstat -g ses to focus on a particular session.

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