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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 processor affinityUse the aff option of the VPCLASS parameter to specify the processors to which you want to bind CPU VPs or AIO VPs. When you assign a CPU VP to a specific CPU, the VP runs only on that CPU. However, other processes can also run on that CPU.
Isolating AIO VPs from CPU VPsOn a system that runs database server and client (or other) applications, you can bind asynchronous I/O (AIO) VPs to the same CPUs to which you bind other application processes through the operating system. In this way, you isolate client applications and database I/O operations from the CPU VPs.

Isolating AIO VPs from CPU VPs

On a system that runs database server and client (or other) applications, you can bind asynchronous I/O (AIO) VPs to the same CPUs to which you bind other application processes through the operating system. In this way, you isolate client applications and database I/O operations from the CPU VPs.

This isolation can be especially helpful when client processes are used for data entry or other operations that require waiting for user input. Because AIO VP activity usually comes in quick bursts followed by idle periods waiting for the disk, you can often interweave client and I/O operations without their unduly impacting each other.

Binding a CPU VP to a processor does not prevent other processes from running on that processor. Application (or other) processes that you do not bind to a CPU are free to run on any available processor. On a computer that is dedicated to the database server, you can leave AIO VPs free to run on any processor, which reduces delays on database operations that are waiting for I/O. Increasing the priority of AIO VPs can further improve performance by ensuring that data is processed quickly once it arrives from disk.