[rules-users] Drools planner: The workingMemory has 1 ConstraintOccurrence(s) in excess

[Geoffrey De Smet]

Op 05-02-13 09:16, Michiel Vermandel schreef:
> Hi,
>
> I am using Drools planner 5.5.0.Final.
> Once again I have the exception "The workingMemory has 1 
> ConstraintOccurrence(s) in excess".
> I have added all relevant planning variables as parameters of the 
> ConstraintOccurrence.
>
> Could the following theory be an explanation for this issue?
>
> My dataset is not that big (not small either).
> Could it be that a certain move is taken twice within the same step 
> (as part of score trap?) which results in the same constraint occurrence?
No, the same move twice in the same step should not cause any trouble.
If you can prove this causes the score corruption, it's a bug in Drools 
Expert.
There have been a bunch of bugfixes in drools, so try drools (-core, 
-compiler, knowledge-api, mvel, ...) 5.5.0-SNAPSHOT:
https://repository.jboss.org/nexus/content/groups/public/org/drools/drools-core/5.5.1-SNAPSHOT/drools-core-5.5.1-20130205.051201-93.pom
If that doesn't help, paste the rule.
>
> I have one other question - maybe related:
> In my configuration I have this:
>
>         <acceptor>
> <planningEntityTabuSize>7</planningEntityTabuSize> <!-- I tested with 
> lower values (5, 3) too -->
>         </acceptor>
>         <forager>
> <pickEarlyType>FIRST_BEST_SCORE_IMPROVING</pickEarlyType>
> <minimalAcceptedSelection>1000</minimalAcceptedSelection>
>         </forager>
>
> Because of the forager configuration a step is sometimes taken after 
> as little as 40 moves, but sometimes the number of moves grows to 
> enormous amounts.
> I think if that happens that the score is no longer improving.
> Is it "normal" that a certain step can make +50k moves and counting?
you're set at 1k minimalAcceptedSelection, so 50k is a lot indeed.
This is probably because the planningEntityTabuSize is to high compared 
to the number of entity's in your dataset.
There's a jira for making planningEntityTabuSize automatically adjust 
itself based on the entity size (which would solve this).
Or it could also be because the number of possible moves (entity size * 
value size) is near 1k.

> Or does indicate once more to a score trap?
No. It indicates that planner's config should scale down automatically.
How many entity's and values do you have?
>
> Thanks
>
> Michiel
>
> -----------------
> http://www.codessentials.com - Your essential software, for free!
> Follow us at http://twitter.com/#!/Codessentials
>
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20130205/424c2d8e/attachment-0001.html