[rules-users] Drools low concurrency/high synchronization? !NOSIG!
Edson Tirelli
tirelli at post.com
Thu Mar 13 16:40:15 EDT 2008
Leon,
This specific problem was fixed in the 4.0.x branch a few weeks ago. I
believe we covered all the scenarios, but in case we missed any, please let
us know asap.
[]s
Edson
2008/3/13, Leon Stein <leon at farecast.com>:
>
> 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 at 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 at valtech.de
> >>>> <mailto:ingomar.otter at 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 at 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 at valtech.de <mailto:ingomar.otter at 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 at lists.jboss.org <mailto:rules-users at lists.jboss.org>
> >>>> https://lists.jboss.org/mailman/listinfo/rules-users
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> --
> >>>> Fernando Meyer http://fmeyer.org
> >>>> JBoss Rules Core Developer
> >>>> fernando at fmeyer.org <mailto:fernando at fmeyer.org>
> >>>>
> ------------------------------------------------------------------------
> >>>>
> >>>> _______________________________________________
> >>>> rules-users mailing list
> >>>> rules-users at lists.jboss.org
> >>>> https://lists.jboss.org/mailman/listinfo/rules-users
> >>>>
> >>>>
> >>> _______________________________________________
> >>> rules-users mailing list
> >>> rules-users at lists.jboss.org
> >>> https://lists.jboss.org/mailman/listinfo/rules-users
> >>>
> >>>
> >>>
> >>
> >>
> >>
> >>
> >
> > ------------------------------------------------------------------------
> >
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> > https://lists.jboss.org/mailman/listinfo/rules-users
> >
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>
--
Edson Tirelli
JBoss Drools Core Development
Office: +55 11 3529-6000
Mobile: +55 11 9287-5646
JBoss, a division of Red Hat @ www.jboss.com
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