Some more details here:
I work on an Event Correlation & Analysis OSS solution that's based on Grails & Drools 5.5.0-Final.
I'm using a stateful knowledge session and only call dispose() when the app is stopped - but all facts
are retracted. The functional testing works fine but as I've mentioned it before when I run the integration
testing it fails, because rules are not fired ('ClearAlertRule' is not fired) when I insert more than 20 facts.
I saw the errors in the drools log but I didn't know if they were relevant for my problem here.
 I've attached two picts which document the right and the wrong behavior of the rule processing
 - also I've listed the rules of my rulebase.

Has anybody an idea?

Cheers,

-markus

//------------------------------
rule 'UpdateAlertRule'
//------------------------------
   dialect  'mvel'
   salience 900
   no-loop
   when
     _event : Event(eventClass == "Event",
        _name:catalog['name'],
                 _category:catalog['category'],
                 _severity:catalog['severity'],
                 _state:catalog['state'],
                 _source:catalog['source'],
                 _subSource:catalog['subSource'],
                 _origin:catalog['origin'],
                 _subOrigin:catalog['subOrigin'],
                 _owner:catalog['owner'],
                 _description:catalog['description'],
                 _selector:("from Alert where " + 
                    "name='" + catalog['name'] + "' " + 
                    "and severity='" + catalog['severity'] + "' " + 
                    "and not state='Closed'"
                 )
              )
     eval(isDuplicate(_event,"UpdateAlertRule",_selector) == true)
   then
System.out.println("UpdateAlertRule is processed.")
     EntityBuilder entityBuilder = new EntityBuilder();
     entityBuilder.addProperty("modifiedBy","UpdateAlertRule");
entityBuilder.addProperty("counter",1);
     AlertHandler alertHandler = new AlertHandler(entityBuilder.getProperties(),_selector);
     alertHandler.update();
     RuleLogHandler ruleLogHandler = new RuleLogHandler();
ruleLogHandler.create("UpdateAlertRule",_name);
   end

//------------------------------
rule 'ClearAlertRule'
//------------------------------
   dialect  'mvel'
   salience 800
   no-loop
   when
     _event : Event(eventClass == "Event",
        _name:catalog['name'] contains 'Info',
                 _category:catalog['category'],
                 _severity:catalog['severity'] == 'Harmless',
                 _state:catalog['state'],
                 _source:catalog['source'],
                 _subSource:catalog['subSource'],
                 _origin:catalog['origin'],
                 _subOrigin:catalog['subOrigin'],
                 _owner:catalog['owner'],
                 _description:catalog['description'],
                 _selector:("from Alert where " + 
                    "name like '%Error'" + 
                    "and not severity='Harmless'" + 
                    "and not state='Closed'"
                 )
              )
   then
System.out.println("ClearAlertRule is processed.")
     EntityBuilder entityBuilder = new EntityBuilder();
     entityBuilder.addProperty("modifiedBy","ClearAlertRule")
entityBuilder.addProperty("state","Closed");
     AlertHandler alertHandler = new AlertHandler(entityBuilder.getProperties(),_selector);
     alertHandler.update();
     RuleLogHandler ruleLogHandler = new RuleLogHandler();
ruleLogHandler.create("ClearAlertRule",_name);
   end

//------------------------------
rule 'CreateAlertRule'
//------------------------------
   dialect  'mvel'
   salience 700
   no-loop
   when
     _event : Event(eventClass == "Event",
        _name:catalog['name'],
                 _category:catalog['category'],
                 _severity:catalog['severity'],
                 _priority:catalog['priority'],
                 _state:catalog['state'],
                 _source:catalog['source'],
                 _subSource:catalog['subSource'],
                 _origin:catalog['origin'],
                 _subOrigin:catalog['subOrigin'],
                 _owner:catalog['owner'],
                 _description:catalog['description'],
                 _selector:("from Alert where " + 
                    "name='" + catalog['name'] + "' " + 
                    "and severity='" + catalog['severity'] + "' " + 
                    "and not state='Closed'"
                 )
              )
     eval(isDuplicate(_event,"CreateAlertRule",_selector) == false)
   then
System.out.println("CreateAlertRule is processed.");
EntityBuilder entityBuilder = new EntityBuilder();
     entityBuilder.addProperty("modifiedBy","CreateAlertRule");
     entityBuilder.addProperty("name",_name);
     entityBuilder.addProperty("category",_category);
     entityBuilder.addProperty("severity",_severity);
     entityBuilder.addProperty("priority",_priority);
     entityBuilder.addProperty("state",_state);
     entityBuilder.addProperty("source",_source);
     entityBuilder.addProperty("subSource",_subSource);
     entityBuilder.addProperty("origin",_origin);
     entityBuilder.addProperty("subOrigin",_subOrigin);
     entityBuilder.addProperty("owner",_owner);
     entityBuilder.addProperty("description",_description);
     AlertHandler alertHandler = new AlertHandler(entityBuilder.getProperties(),_selector);
    alertHandler.create();
    RuleLogHandler ruleLogHandler = new RuleLogHandler();
ruleLogHandler.create("CreateAlertRule",_name);
   end

//------------------------------
rule 'EventRetractionRule'
//------------------------------
   dialect  'mvel'
   salience 1
   no-loop
   when
     _event : Event(eventClass == "Event",

        _name:catalog['name'] not contains 'Timer'
               
               
              )
   then
System.out.println("EventRetractionRule is processed.");
retract(_event);
     RuleLogHandler ruleLogHandler = new RuleLogHandler();
ruleLogHandler.create("EventRetractionRule",_name);
   end