CME in DefaultAgenda.evaluateEagerList -------------------------------------- Key: DROOLS-3413 URL: https://issues.jboss.org/browse/DROOLS-3413 Project: Drools Issue Type: Bug Components: core engine Affects Versions: 6.5.0.Final Environment: RHEL 6.10 x86_64 Drools embedded in OpenNMS Meridian 2017.1.5. Reporter: Will Keaney Assignee: Mario Fusco Priority: Major I have a KieSession that runs in Stream processing mode, which is throwing frequent ConcurrentModificationExceptions in evaluateEagerList: {code}Exception in thread "FireTask" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) at java.util.ArrayList$Itr.next(ArrayList.java:851) at org.drools.core.phreak.PhreakFromNode.doLeftUpdates(PhreakFromNode.java:176) at org.drools.core.phreak.PhreakFromNode.doNode(PhreakFromNode.java:64) at org.drools.core.phreak.RuleNetworkEvaluator.evalNode(RuleNetworkEvaluator.java:355) at org.drools.core.phreak.RuleNetworkEvaluator.innerEval(RuleNetworkEvaluator.java:301) at org.drools.core.phreak.RuleNetworkEvaluator.outerEval(RuleNetworkEvaluator.java:136) at org.drools.core.phreak.RuleNetworkEvaluator.evaluateNetwork(RuleNetworkEvaluator.java:94) at org.drools.core.phreak.RuleExecutor.evaluateNetwork(RuleExecutor.java:65) at org.drools.core.common.DefaultAgenda.evaluateEagerList(DefaultAgenda.java:983) at org.drools.core.phreak.RuleExecutor.haltRuleFiring(RuleExecutor.java:233) at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:138) at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:74) at org.drools.core.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:970) at org.drools.core.common.DefaultAgenda.fireLoop(DefaultAgenda.java:1312) at org.drools.core.common.DefaultAgenda.fireUntilHalt(DefaultAgenda.java:1232) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireUntilHalt(StatefulKnowledgeSessionImpl.java:1398) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireUntilHalt(StatefulKnowledgeSessionImpl.java:1377) at org.opennms.netmgt.correlation.drools.DroolsCorrelationEngine.lambda$initialize$2(DroolsCorrelationEngine.java:217) at java.lang.Thread.run(Thread.java:745){code} Many of the rules in this KB have {{no-loop true}}.