We ran into this problem after upgrading from 3.0.* to 4.0.4. Is there a JIRA issue filed for this? I see a few MVEL-related issues scoped for 4.0.5 and 5.0 releases, but nothing that looks like specifically covering this problem.

Thanks, Leon Mark Proctor wrote: > This looks different to what was fixed in 4.0.4. I'm cc'ing brockm to > get his feedback as it looks like an MVEL bug on accessors. > > Mark > Fernando Meyer wrote: > >> Hi Ingomar, >> >> Which drools version are you using? We made improvements on 4.0.4, >> that fixes concurrency issues on mvel core, so if you aren't using it >> please do an update and try test against your environment. >> >> Please let me know if your problems go away when you upgrade. >> >> Thanks >> >> On Jan 22, 2008 11:13 AM, Ingomar Otter <ingomar.otter(a)valtech.de >> <mailto:ingomar.otter@valtech.de>> wrote: >> >> Folks, >> I am currently trying to scale our implementation by farming out >> request into mutliple threads. I am on a 4 CPU Mac. >> A few things I am wondering about: >> 1. Although I see an increase in CPU load when going from single >> to multi-threaded processing the throughput increased marginally. >> I am pretty sure that my measurements are correct. I have checked >> the GC and this is not the source of congestion. My question here >> is whether Drools is using lot's of synchronization that may >> explain this. >> 2. When I share the RuleBase accross threads (which I think is >> valid?) I get interesting errors during execution. eg: >> >> org.drools.RuntimeDroolsException : Exception executing predicate >> org.drools.base.mvel.MVELPredicateExpression@bb981e >> atorg.drools.rule.PredicateConstraint.isAllowedCachedRight( >> PredicateConstraint.java:246) >> at >> >> org.drools.common.TripleBetaConstraints.isAllowedCachedRight(TripleBetaConstraints.java:200) >> >> atorg.drools.reteoo.JoinNode.assertObject(JoinNode.java:150) >> >> >> atorg.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject(CompositeObjectSinkAdapter.java:318) >> >> atorg.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:153) >> at org.drools.reteoo.Rete.assertObject(Rete.java:175) >> atorg.drools.reteoo.ReteooRuleBase.assertObject >> (ReteooRuleBase.java:192) >> at >> >> org.drools.reteoo.ReteooWorkingMemory.doInsert(ReteooWorkingMemory.java:71) >> >> at >> >> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:909) >> >> >> atorg.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:881) >> >> >> atorg.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:682) >> >> atxxxx.DroolsPD.validate(DroolsPD.java:66) >> at xxxx.DroolsMTRunner.run(DroolsMTRunner.java:30) >> at java.lang.Thread.run(Thread.java:552) >> Caused by: org.mvel.CompileException: cannot invoke getter: >> getSAClass [declr.class: xxx.AbstractSA; act.class: null] >> atorg.mvel.optimizers.impl.refl.GetterAccessor.getValue( >> GetterAccessor.java:52) >> at >> >> org.mvel.optimizers.impl.refl.VariableAccessor.getValue(VariableAccessor.java:39) >> >> at >> >> org.mvel.ast.VariableDeepPropertyNode.getReducedValueAccelerated(VariableDeepPropertyNode.java:22) >> >> atorg.mvel.ast.PropertyASTNode.getReducedValueAccelerated(PropertyASTNode.java:21) >> at >> >> org.mvel.ast.BinaryOperation.getReducedValueAccelerated(BinaryOperation.java:21) >> >> at org.mvel.MVELRuntime.execute(MVELRuntime.java:88) >> at org.mvel.CompiledExpression.getValue(CompiledExpression.java:111) >> >> atorg.mvel.MVEL.executeExpression(MVEL.java:235) >> at >> >> org.drools.base.mvel.MVELPredicateExpression.evaluate(MVELPredicateExpression.java:36) >> >> >> atorg.drools.rule.PredicateConstraint.isAllowedCachedRight(PredicateConstraint.java:240) >> ... 13 more >> Caused by: java.lang.NullPointerException >> atsun.reflect.GeneratedMethodAccessor6.invoke (Unknown Source) >> atsun.reflect.DelegatingMethodAccessorImpl.invoke( >> DelegatingMethodAccessorImpl.java:25) >> atjava.lang.reflect.Method.invoke( Method.java:324) >> at >> >> org.mvel.optimizers.impl.refl.GetterAccessor.getValue(GetterAccessor.java:42) >> >> ... 22 more >> >> Details: >> * I use StatelessSessions which are private to the threads >> * No data is shared between threads (with the exception of the >> RuleBase, as outline above) >> * I am on JDK 1.5 >> >> I would be grateful for any pointers for 'correct' use of Drools >> in an MT environment. >> Cheers, >> Ingomar >> >> >> Ingomar Otter >> Chief Technology Officer >> ingomar.otter(a)valtech.de <mailto:ingomar.otter@valtech.de> >> Mobile: +49 172 2367867 >> >> Valtech GmbH >> Bahnstraße 16 >> 40212 Düsseldorf >> Germany >> >> Phone: +49 (0)211 179237-0 >> Fax: +49 211 179237-19 >> >> www.valtech.de <http://www.valtech.de/> >> >> Geschäftsführer: Ingo Kriescher >> Amtsgericht Düsseldorf HRB48672 >> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org <mailto:rules-users@lists.jboss.org> >> https://lists.jboss.org/mailman/listinfo/rules-users >> >> >> >> >> -- >> Fernando Meyer http://fmeyer.org >> JBoss Rules Core Developer >> fernando(a)fmeyer.org <mailto:fernando@fmeyer.org> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> >> > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > >

I'll test with the latest from 4.0.x branch, in the meanwhile, more info on the actual error: Stack trace: org.drools.RuntimeDroolsException: Exception executing predicate org.drools.base.mvel.MVELPredicateExpression@3863aa2c at org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java :216) at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:132) at org.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject( CompositeObjectSinkAdapter.java:318) at org.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:153) at org.drools.reteoo.Rete.assertObject(Rete.java:175) at org.drools.reteoo.ReteooRuleBase.assertObject(ReteooRuleBase.java:192) at org.drools.reteoo.ReteooWorkingMemory.doInsert(ReteooWorkingMemory.java :71) at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java :909) at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java :881) at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java :682) <removed> Caused by: org.mvel.CompileException: cannot invoke getter: getBar [declr.class: org.example.Foo; act.class: null] at org.mvel.optimizers.impl.refl.GetterAccessor.getValue(GetterAccessor.java :52) at org.mvel.optimizers.impl.refl.VariableAccessor.getValue( VariableAccessor.java:39) at org.mvel.ast.VariableDeepPropertyNode.getReducedValueAccelerated( VariableDeepPropertyNode.java:22) at org.mvel.ast.PropertyASTNode.getReducedValueAccelerated( PropertyASTNode.java:21) at org.mvel.ast.BinaryOperation.getReducedValueAccelerated( BinaryOperation.java:21) at org.mvel.MVELRuntime.execute(MVELRuntime.java:88) at org.mvel.CompiledExpression.getValue(CompiledExpression.java :111) at org.mvel.MVEL.executeExpression(MVEL.java:235) at org.drools.base.mvel.MVELPredicateExpression.evaluate( MVELPredicateExpression.java:36) at org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java :210) ... 41 more Caused by: java.lang.NullPointerException at sun.reflect.GeneratedMethodAccessor292.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke( DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.mvel.optimizers.impl.refl.GetterAccessor.getValue(GetterAccessor.java :42) ... 50 more - Only occurs on multi-cpu boxes (Linux, Sun JRE 1.5.0_06, 64 bit) under heavy load with simultaneous sessions running against same rule base with thousands of facts in each session. - The rule where exception occurs traverses properties of inserted object (foo.bar expression): rule "XYZ" when foo : FooHolder(foo.bar == Bar.GREEN) ... then ... end The traversed objects are not shared between sessions, and properties are never null. Leon Mark Proctor wrote: > Leon S wrote: >> We ran into this problem after upgrading from 3.0.* to 4.0.4. >> >> Is there a JIRA issue filed for this? I see a few MVEL-related issues scoped >> for 4.0.5 and 5.0 releases, but nothing that looks like specifically >> covering this problem. >> >> > The user who reported this has not provided more information on how > this is happening, nor have they confirmed that is or is not fixed in > 4.0.x. My advice is quickly test your code against 4.0.x and let us > know if there is a problem. There is no way we can determine if there > is or isn't a problem from the stack trace given at the start of this > conversation thread. > http://anonsvn.labs.jboss.com/labs/jbossrules/branches/4.0.x/ >> Thanks, >> >> Leon >> >> >> Mark Proctor wrote: >> >>> This looks different to what was fixed in 4.0.4. I'm cc'ing brockm to >>> get his feedback as it looks like an MVEL bug on accessors. >>> >>> Mark >>> Fernando Meyer wrote: >>> >>>> Hi Ingomar, >>>> >>>> Which drools version are you using? We made improvements on 4.0.4, >>>> that fixes concurrency issues on mvel core, so if you aren't using it >>>> please do an update and try test against your environment. >>>> >>>> Please let me know if your problems go away when you upgrade. >>>> >>>> Thanks >>>> >>>> On Jan 22, 2008 11:13 AM, Ingomar Otter <ingomar.otter(a)valtech.de >>>> <mailto:ingomar.otter@valtech.de>> wrote: >>>> >>>> Folks, >>>> I am currently trying to scale our implementation by farming out >>>> request into mutliple threads. I am on a 4 CPU Mac. >>>> A few things I am wondering about: >>>> 1. Although I see an increase in CPU load when going from single >>>> to multi-threaded processing the throughput increased marginally. >>>> I am pretty sure that my measurements are correct. I have checked >>>> the GC and this is not the source of congestion. My question here >>>> is whether Drools is using lot's of synchronization that may >>>> explain this. >>>> 2. When I share the RuleBase accross threads (which I think is >>>> valid?) I get interesting errors during execution. eg: >>>> >>>> org.drools.RuntimeDroolsException : Exception executing predicate >>>> org.drools.base.mvel.MVELPredicateExpression@bb981e >>>> atorg.drools.rule.PredicateConstraint.isAllowedCachedRight( >>>> PredicateConstraint.java:246) >>>> at >>>> >>>> org.drools.common.TripleBetaConstraints.isAllowedCachedRight( TripleBetaConstraints.java:200) >>>> >>>> atorg.drools.reteoo.JoinNode.assertObject(JoinNode.java:150) >>>> >>>> >>>> atorg.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject( CompositeObjectSinkAdapter.java:318) >>>> >>>> atorg.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java :153) >>>> at org.drools.reteoo.Rete.assertObject(Rete.java:175) >>>> atorg.drools.reteoo.ReteooRuleBase.assertObject >>>> (ReteooRuleBase.java:192) >>>> at >>>> >>>> org.drools.reteoo.ReteooWorkingMemory.doInsert( ReteooWorkingMemory.java:71) >>>> >>>> at >>>> >>>> org.drools.common.AbstractWorkingMemory.insert( AbstractWorkingMemory.java:909) >>>> >>>> >>>> atorg.drools.common.AbstractWorkingMemory.insert( AbstractWorkingMemory.java:881) >>>> >>>> >>>> atorg.drools.common.AbstractWorkingMemory.insert( AbstractWorkingMemory.java:682) >>>> >>>> atxxxx.DroolsPD.validate(DroolsPD.java:66) >>>> at xxxx.DroolsMTRunner.run(DroolsMTRunner.java:30) >>>> at java.lang.Thread.run(Thread.java:552) >>>> Caused by: org.mvel.CompileException: cannot invoke getter: >>>> getSAClass [declr.class: xxx.AbstractSA; act.class: null] >>>> atorg.mvel.optimizers.impl.refl.GetterAccessor.getValue( >>>> GetterAccessor.java:52) >>>> at >>>> >>>> org.mvel.optimizers.impl.refl.VariableAccessor.getValue( VariableAccessor.java:39) >>>> >>>> at >>>> >>>> org.mvel.ast.VariableDeepPropertyNode.getReducedValueAccelerated( VariableDeepPropertyNode.java:22) >>>> >>>> atorg.mvel.ast.PropertyASTNode.getReducedValueAccelerated( PropertyASTNode.java:21) >>>> at >>>> >>>> org.mvel.ast.BinaryOperation.getReducedValueAccelerated( BinaryOperation.java:21) >>>> >>>> at org.mvel.MVELRuntime.execute(MVELRuntime.java:88) >>>> at org.mvel.CompiledExpression.getValue(CompiledExpression.java :111) >>>> >>>> atorg.mvel.MVEL.executeExpression(MVEL.java:235) >>>> at >>>> >>>> org.drools.base.mvel.MVELPredicateExpression.evaluate( MVELPredicateExpression.java:36) >>>> >>>> >>>> atorg.drools.rule.PredicateConstraint.isAllowedCachedRight( PredicateConstraint.java:240) >>>> ... 13 more >>>> Caused by: java.lang.NullPointerException >>>> atsun.reflect.GeneratedMethodAccessor6.invoke (Unknown Source) >>>> atsun.reflect.DelegatingMethodAccessorImpl.invoke( >>>> DelegatingMethodAccessorImpl.java:25) >>>> atjava.lang.reflect.Method.invoke( Method.java:324) >>>> at >>>> >>>> org.mvel.optimizers.impl.refl.GetterAccessor.getValue( GetterAccessor.java:42) >>>> >>>> ... 22 more >>>> >>>> Details: >>>> * I use StatelessSessions which are private to the threads >>>> * No data is shared between threads (with the exception of the >>>> RuleBase, as outline above) >>>> * I am on JDK 1.5 >>>> >>>> I would be grateful for any pointers for 'correct' use of Drools >>>> in an MT environment. >>>> Cheers, >>>> Ingomar >>>> >>>> >>>> Ingomar Otter >>>> Chief Technology Officer >>>> ingomar.otter(a)valtech.de <mailto:ingomar.otter@valtech.de> >>>> Mobile: +49 172 2367867 >>>> >>>> Valtech GmbH >>>> Bahnstraße 16 >>>> 40212 Düsseldorf >>>> Germany >>>> >>>> Phone: +49 (0)211 179237-0 >>>> Fax: +49 211 179237-19 >>>> >>>> www.valtech.de <http://www.valtech.de/> >>>> >>>> Geschäftsführer: Ingo Kriescher >>>> Amtsgericht Düsseldorf HRB48672 >>>> >>>> >>>> _______________________________________________ >>>> rules-users mailing list >>>> rules-users(a)lists.jboss.org <mailto:rules-users@lists.jboss.org> >>>> https://lists.jboss.org/mailman/listinfo/rules-users >>>> >>>> >>>> >>>> >>>> -- >>>> Fernando Meyer http://fmeyer.org >>>> JBoss Rules Core Developer >>>> fernando(a)fmeyer.org <mailto:fernando@fmeyer.org> >>>> ------------------------------------------------------------------------ >>>> >>>> _______________________________________________ >>>> rules-users mailing list >>>> rules-users(a)lists.jboss.org >>>> https://lists.jboss.org/mailman/listinfo/rules-users >>>> >>>> >>> _______________________________________________ >>> rules-users mailing list >>> rules-users(a)lists.jboss.org >>> https://lists.jboss.org/mailman/listinfo/rules-users >>> >>> >>> >> >> >> >> > > ------------------------------------------------------------------------ > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users