Product: OpenFusion Notification Service

Version: ALL

Description:

Receiving an IMP_LIMIT exception when calling push_structured_events?

Resolution:

There are two cases where you can see an IMP_LIMIT exception being thrown:

1. If you set the MaxQueueLength Admin property to a value and the RejectNewEvents Admin property to true
2. If you set the MaxMemoryUsage QoS property to a value and the MaxMemoryUsagePolicy QoS property to RejectEvents

When the value of MaxQueueLength or MaxMemoryUsage value is reached the Notification Service will not let any more events enter the channel. In order to notify the suppliers that this is the case an IMP_LIMIT exception is thrown. The IMP_LIMIT exception can be caught by the suppliers and then they can stop sending events until they no longer get the exception. This allows you to control the number of events within the Notification Service. This is normal behaviour.

The IMP_LIMIT will not be thrown reliably with structured suppliers using auto-sequencing. Auto-sequencing is new behaviour that was added in OpenFusion v4.