Allocating Resources for Parallel Database Queries

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

When you configure the database server, consider how the use of PDQ affects users of OLTP, decision-support applications, and other applications.

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.