ASA Database Administration Guide
The Database Server
The database server
Database server options
Set the maximum number of requests that can concurrently execute blocking system calls.
{ dbsrv9 | dbeng9 } -gx
integer ...
Windows 95/98/Me, Windows NT/2000/XP
This option is only of use on Windows NT. On other platforms the -gn value is equivalent to the -gt value.
Meaningful values are in the range specified by the -gt option value and the -gn option value. By default, this option is set to a value one greater than the number of CPUs on the machine. The additional process permits the use of remote data access between databases on a single database server.
The primary cost of increasing -gx is reduced address space (not physical memory) available for the cache. This option is only of use if you are using omni, java, or external stored procedures (and in the case of java/external stored procedures, those if features are being used to implement servers). If you are using omni/java/external stored procedures and the engine hangs for no apparent reason, increasing -gx might solve the problem. Setting the -gx option beyond the -gn option has no benefit.
You may want to increase the option setting beyond the default to reserve capacity for external tasks, separate from standard database tasks. For example, you may want to increase the value of -gx by one for each concurrent connection using remote data access, or for connections using Java in the database to listen on an external port. In other circumstances, this option should be left at the default value.
On UNIX, each task is executed in its own thread, so that the number of tasks (-gn) also determines the number of threads.
Controlling threading from the command line