IBM BPM, V8.0.1, All platforms > Tuning > Advanced tuning > Business Process Choreographer tuning > Tuning BPEL processes > Tuning long-running processes

Tuning the application server

Use this task to tune the application server.

Before you start this task, you must have specified the initial settings for the database.

To ensure that Business Process Choreographer can perform optimally, you need to adjust the server settings.

Procedure

1. Estimate the application server resources that you need for each Business Process Choreographer configuration.

   1. One data source to read and write BPEL process state information to a database: BPEDataSourceDb2 in the server scope DB2 Universal JDBC Driver Provider (XA)
   2. Calculate the maximum concurrency of transactions, t, for the process navigation by adding the following:

      • The maximum number of clients concurrently connected through the Business Process Choreographer API

      • The number of concurrent endpoints defined in the JMS activation specification BPEInternalActivationSpec

      • The number of concurrent endpoints defined in the JMS activation specification HTMInternalActivationSpec

      To view the activation specifications for the process server, in the administrative console, click Resources > JMS > JMS Providers > Default messaging > Activation specifications.

   3. For the Business Process Choreographer database, calculate the number of parallel JDBC connections required, p = 1.1 * t

      The value of p must not be greater than the number of connections allowed by the database.

   4. For the messaging database, calculate the number of parallel JDBC connections required, m = t + x, where x is the number of additional JMS sessions to allow for overload situations where additional messages are generated and must be served. Unless a high number of error situations, such as rollbacks occur, set x to 5.
2. Tune the JDBC provider settings for the Business Process Choreographer database (BPEDB).
   1. Set Max Connections to the value p. The value of p must not be greater than the number of connections allowed by the database.
   2. Set the SQL Statement cache size to 300.
3. Tune the data sources for the data stores used by the messaging engines for the Business Process Choreographer, SCA application, SCA system, and CEI buses.
   1. Set Max Connections to the value p. Ensure that if one database is used for all messaging engines, the messaging database supports 4 * m connections.
   2. Set the SQL Statement cache size to 50.
4. Tune the heap size.

   Here are some guidelines for the size of the server heap on 32-bit systems.

   • 256 MB is too low, and results in poor performance.
   • 512 MB is adequate as an initial heap size for many systems.
   • 1280 MB is a good upper limit in general, but you can increase the heap size based on the garbage collection behavior.

   For 64-bit systems, you can set the heap limit much higher. Start with a heap size of 2 GB and observer the garbage collection output during stress tests to see if you need to further increase the heap limit.

5. Tune any services used by your BPEL processes. Verify that your supporting services are tuned to cope with the degree of concurrency and load demands that Business Process Choreographer makes on the service.

Results

The application server is tuned for improved performance.

Tuning long-running processes

Related tasks:

Balancing the hardware resources
Tuning the JDBC data source of a messaging engine in WebSphere Application Server

Related information:

Specifying initial DB2 database settings