Adding BTS virtual processors to run multiple queries simultaneously

You can increase the number of basic text search queries or other index operations that can run at the same time by adding additional BTS virtual processors.

About this task

Each Basic Text Search function, including bts_contains(), runs in a BTS virtual processor without yielding. If basic text search queries are slow because multiple users are running queries at the same time, you can add more BTS virtual processors so that queries run simultaneously, each in their own virtual processor.

To dynamically add BTS virtual processors for the current database server session:

Procedure

Run the onmode -p command, specifying the number of virtual processors to add and the BTS virtual processor class. For example, the following command adds three BTS virtual processors: onmode -p 3 bts

Example

Alternatively, you can use the SQL administration API task() or admin() function with the onmode and p arguments to add BTS virtual processors.

To permanently increase the number of BTS virtual processors, set the value of the VPCLASS bts configuration parameter in the onconfig file and then restart the database server. If the onconfig file contains an existing entry for the VPCLASS bts configuration parameter, update that entry; otherwise, add a new entry for the VPCLASS bts configuration parameter.

For more information about the onmode utility or the SQL administration API, see the Informix® Administrator's Reference,