Hello. I'm testing event processing in Drools, and after some basic tests, I have some questions about event life cycle management. According to the documentation, in stream mode, events may be automatically discarded by the engine when no rule, currently or in the future, applies to them. In the following rule set (at the end of my post), the rule named "Processing new alert event" is expected to be executed when a new 'alert' notification event arrives and no previous alert exists. After an elementary test, the first matching notification produces the expected behavior and generates the Alert. But if a second matching notification is inserted, the rule is ignored as expected, since the Alert is already set, but the event object seems to be put durably in memory. When a 'stop' notification is inserted, the Alert object is cleared by the rule "Processing stop event after alert", as expected, but the second 'alert' notification that should be forgotten is raised from the memory and the first rule is fired again, creating an undesired second Alert. I've tried a workaround adding an "opposite rule" to check the processing of an 'alert' notification when there is a current Alert. As at the moment the notification object is inserted the two rules are candidate in the agenda, both are executed. I suppose I could try, for example, adding salience values to make the rules execute in a deterministic order... As you can see, I've added explicit deletion of the notification objects in the rules, and all seems to work as needed. But it seems really a bit cimplicated, and contradictory with the documentation... What did I miss ? Thanks for your help. Regards? Here the rule set : -- View this message in context: http://drools.46999.n3.nabble.com/Drools-Fusion-CEP-event-life-cycle-tp40... Sent from the Drools: User forum mailing list archive at Nabble.com.