Guidelines for Executing Without a Transaction

To execute a business process without a transaction, select notSupported from the Transaction list when creating a BPEL process in the Create BPEL Process dialog.

When set, the following behavior occurs:

All XA distributed transaction benefits are disabled.

When a business process is configured to run in non-transactional mode, the instance execution is not wrapped in an XA transaction, resulting in potential duplicate instances, but no loss of message(s). As there is no overhead of a transaction, the non-transactional mode provides better performance. You can use the non-transactional option where duplicate instances are acceptable.
The business process cannot invoke any partner that expects to participate in a transaction (that is, the partner has the TransactionAttribute set to MANDATORY).
The invoke from the business process is fire and forget (that is, once the invoke is finished, it is delivered to the partner. Even if the invoker's transaction rolls back afterwards, the invoke message is not rolled back).

Even with bpel.config.transaction set to notSupported, the dehydration point starts a transaction to save the internal BPEL process engine state into the back end. This means the dehydration concept still applies for the business process. This feature only guarantees that business process activities such as an assign, an invoke, and others are executed without a transaction.

This property configures the transaction behavior of a BPEL instance in the case of initiating calls. Table 13-5 describes the behavior of the BPEL instance based on the bpel.config.transaction property setting.

Table 13-5 BPEL Process Instance Behavior Based on transaction Property Settings

Transaction Type	transaction = requiresNew	transaction = required	transaction = notSupported
Request/response (initiating)	A new transaction is created for the execution. The existing transaction (if there is one) is suspended.	The process joins a caller's transaction (if there is one) or creates a new transaction (if there is not a transaction).	Business process activities are executed without a transaction. The transaction is only used to save internal service engine/instance state and audit details. Any `bpelx:rollback` fault is not propagated back to the client because the current instance does not participate in the client's transaction.
One-way (initiating, `bpel.config.oneWayDeliveryPolicy=sync`)	A new transaction is created for the execution and the existing transaction (if there is one) is suspended.	The invoke message is processed using the same thread in the same transaction.	Business process activities are executed without a transaction. A transaction is only used to save internal service engine/instance state and audit details. Any `bpelx:rollback` fault is not propagated back to the client.
One-way asynchronous	Not applicable.	Not applicable.	Business process activities are executed without a transaction. The transaction is only used to save internal service engine/instance state and audit details.