ASA Database Administration Guide
The Database Server
The database server
Database server options
Set the maximum number of active requests (both user and system) that the database server can handle concurrently.
{ dbsrv9 | dbeng9 } -gn
integer ...
All operating systems and servers.
Set the number of active user and system requests that the databse server can handle concurrently. If the maximum number of active requests are already in use when the database server receives an additional request, the new request must wait until another request is completed.
Each connection uses a thread for each request, and when the request is completed the thread is returned to the pool for use by other connections. As no connection can have more than one request in progress at one time, no connection uses more than one thread at a time. An exception to this rule is if a Java application uses threads. Each thread in the Java application is a database server execution thread.
The default is 20 threads for the network database server, and 10 threads for the personal database server. The number of threads cannot be greater than the number of server connections, so the maximum number of threads for the personal database server is also 10.
You may want investigate the Performance Monitor readings for Requests: Active and Requests: Unscheduled. If the number of active requests is always less than -gn, you can lower -gn. If the number of total requests (active + unscheduled) is often larger than -gn, then you might want to increase -gn. The Performance Monitor is not available for UNIX or Linux platforms.
Controlling threading from the command line