AutoSys and Database Connections (DB_CONNECTIONS) for WAAE r4.X and r11.X

Document ID : KB000009354
Last Modified Date : 14/02/2018
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Introduction:

The purpose of this document is to explain how AutoSys uses database connections (processes) and expand on the current documentation of the AutoSys 11.0 DB_CONNECTIONS parameter.

Note: This parameter can affect operating system and database performance as well as performance of various Workload Automation components, including Workload Control Center. Please consult with CA Support before applying or modifying this parameter.

Environment:
CA Workload Automation AE 4.xCA Workload Automation AE 11.x
Instructions:

AutoSys 4.x Database Connections

In AutoSys 4.x the number of database connections is influenced by the EPCount parameter in the $AUTOUSER/config.$AUTOSERV file or in the AutoSys Admin UI on Windows. One database connection is made for each EP. Database connections are also created by client utilities in AutoSys 4.x. These client utility database connections only exist for the lifetime of the client utility transaction.

AutoSys 11.0 Database Connections

In AutoSys 11.0 the Scheduler and Application Servers maintain a constant pool of database connections.

The number of connections can be control by using the environment variable DB_CONNECTIONS.

The current documentation for DB_CONNECTIONS is as follows:

DB_CONNECTIONS
Controls the maximum number of database connections allotted to the Scheduler. Increasing this value increases the Scheduler's ability to perform simultaneous database operations. 
Default: 16
Limit: 1 to 128
Note: The Application Server also shares the same DB_CONNECTIONS tuning parameter. If the Scheduler and Application Server are run on the same Windows computer, then this value will be applied to both processes upon startup.
Note: The Application Server also shares the same DB_CONNECTIONS tuning parameter. If you set this value in the environment script files located in the $AUTOUSER directory and start the Scheduler and Application Server on the same UNIX computer after sourcing the environment, then this value will be applied to both processes upon startup.

In AutoSys 11.0 the client utilities, by default, do not access the database directly.

Client utility requests are routed through the Application Server, which uses its database connection to fulfill the request.

The connections remain open and reserved until the Application Server(s) and Scheduler(s) are stopped.

Additional Notes

The default Application Server setting is 32.
There is an additional 1 db_monitor connection (process) per Scheduler and Application Server. 
A tie-breaker scheduler will reserve between 2-5 connections by default.
Running in HA mode will result in an additional connection (process).

It is recommended to set this parameter within the $AUTOUSER/autosys.sh.$hostname file (r11.0) on Linux/Unix. 
This parameter must be set in the environment and cannot be set via the $AUTOUSER/config.$AUTOSERV file. 
For Windows it should be an environment variable set at the System level.

Additional Information:

Oracle Notes

The DB_CONNECTIONS parameter is related to the Oracle setting PROCESSES. The default Oracle value for PROCESSES is 25. The default values of DB_FILE_MULTIBLOCK_READ_COUNT and SESSIONS are derived from PROCESSES.

To check the current number of connections:

 

   SELECT count(*) FROM v$process;