Troubleshooting event sequencing

Refer to the information in this topic if you are experiencing difficulty with event sequencing.

Problems with the event sequencing qualifier

Ensure that your component definition is correct:
  • Is the event sequencing qualifier set on the method? Event sequencing validation fails if the qualifier is erroneously set on the interface.
  • Is the parameter name valid?
  • Is the xpath element valid, and does it correctly resolve to a primitive?
  • Is there a single eventSequencing element for the method? Each method supports only one eventSequencing element.
  • Is there a single keySpecification element for the method? Each method supports only one keySpecification element.

Deadlocks

Deadlocks occur when an invoked operation with a lock invokes another operation on the same component using the same event sequencing key and group. You can resolve a deadlock by using the esAdmin command to list and release the current lock.

To avoid deadlocks, carefully consider dependencies when implementing event sequencing. Ensure that operations with circular dependencies are in different event sequencing groups.

Deadlocks with a BPEL process

Deadlocks can occur when event sequencing is used with Business Process Execution Language (BPEL) processes. Deadlocks are caused by setting event sequencing qualifiers on operations that correspond to both of the following activities:
  • Multiple instantiating receive or pick activities, where the createInstance attribute is set to yes
  • Correlation set specifications with an initiation attribute set to join

Resolve this type of deadlock by using the esAdmin command to list and release the current lock. To prevent further deadlocks, ensure that these types of dependent operations are put into different event sequencing groups.


Last updated: Tue 31 Oct 2006 09:53:28

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