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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.
Parallel database query (PDQ)You can manage how the database server performs PDQ and you can monitor the resources that the database server uses for PDQ.
The allocation of resources for parallel database queriesWhen you configure the database server, consider how the use of PDQ affects users of OLTP, decision-support (DSS) applications, and other applications. Then you can plan how to allocate resources for PDQ.

The allocation of resources for parallel database queries

When you configure the database server, consider how the use of PDQ affects users of OLTP, decision-support (DSS) applications, and other applications. Then you can plan how to allocate resources for PDQ.

When the database server uses PDQ to perform a query in parallel, it puts a heavy load on the operating system. In particular, PDQ exploits the following resources:

Memory
CPU VPs
Disk I/O (to fragmented tables and temporary table space)
Scan threads

You can control how the database server uses resources in the following ways:

Limit the priority of parallel database queries.
Adjust the amount of memory.
Limit the number of scan threads.
Limit the number of concurrent queries.