[rules-users] Re: Drools-solver performance optimizations?

[Wim Vancroonenburg]

To be honest, I do not know if I have to insert a new 
IntConstraintOccurrence. I'm kind of following the Drools Solver examples 
and docs here. Also I have to conform to a certain objective function (that 
was defined in literature), and I know that, at the moment, my rules 
calculate the same value for the objective function for several given 
solutions. So if I were to change my rules, they would have to generate the 
same result. And I do not really know how I would have to change them 
exactly using your approach.

Do you have any tips for that? Perhaps a small example or so?

Sincerely

Wim Vancroonenburg

----- Original Message ----- 
From: "Greg Barton" <greg_barton at yahoo.com>
Newsgroups: gmane.comp.java.drools.user
To: "Rules Users List" <rules-users at lists.jboss.org>
Sent: Thursday, February 12, 2009 4:31 PM
Subject: Re: Drools-solver performance optimizations?


> Do you need to insert new IntConstraintOccurrence instances?  If you had 
> an accumulator object in working memory that you matched on in the rule 
> conditions you could eliminate one object creation and one insert for each 
> rule that matches a **Constraint object.  That could free up lots of cpu 
> and memory usage.  The calcScore rule would simply match on the 
> accumulator object.
>
> --- On Wed, 2/11/09, Wim Vancroonenburg <ikbenvanmars at gmail.com> wrote:
>
>> From: Wim Vancroonenburg <ikbenvanmars at gmail.com>
>> Subject: [rules-users] Drools-solver performance optimizations?
>> To: rules-users at lists.jboss.org
>> Date: Wednesday, February 11, 2009, 12:59 PM
>> Hi,
>>
>> I'm a student currently evaluating Drools Solver for my
>> dissertation. I am
>> currently trying to solve an optimization problem with two
>> different solvers
>> (one of which is Drools Solver) and I am comparing the
>> results with earlier
>> obtained results from literature. However I am having some
>> troubles with the
>> performance of Drools Solver, and I was hoping if someone
>> could look at my
>> rules to see if they could be tuned:
>>
>> rule
>> "patientsToBeAssignedToRoomsOfAppropriateSex"
>>         when
>>                 $n : Night();
>>                 $room : Room(sexRestriction ==
>> Sex.Dependent && capacity >
>> 1);
>>                 $genders : ArrayList(size>1) from
>> collect(
>> PatientStay(bed.room == $room, night == $n) );
>>                 exists PatientStay(bed.room == $room, night
>> == $n, $a :
>> admission,
>> eval(((PatientStay)$genders.get(0)).getAdmission().getPatient().getSex()
>> !=
>> $a.getPatient().getSex()));
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("patientsToBeAssignedToRoomsOfAppropriateSex",ConstraintType.NEGATIVE_HARD,50,$room,$n));
>> end
>>
>> rule "hasRequiredRoomProperties"
>>         when
>>                 $pr : RequiredRoomPropertiesConstraint($a :
>> admission, $r :
>> room, $w : weight );
>>                 $ps : PatientStay(admission == $a, bed.room
>> == $r);
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("hasPreferredRoomProperties",ConstraintType.NEGATIVE_SOFT,50*$w,$ps));
>> end
>>
>> rule "unplannedTransfers"
>>         when
>>                 $ps : PatientStay($a : admission, $b : bed,
>> $n : night);
>>                 $ps2 : PatientStay(admission == $a, bed !=
>> $b, $n2 :
>> night,eval($n.getIndex()+1 == $n2.getIndex()));
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("unplannedTransfers",ConstraintType.NEGATIVE_SOFT,110,$ps,$ps2));
>> end
>>
>> rule "hasPreferredRoomProperties"
>>         when
>>                 $pr : PreferredRoomPropertiesConstraint($a
>> : admission, $r :
>> room, $w : weight );
>>                 $ps : PatientStay(admission == $a, bed.room
>> == $r);
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("hasPreferredRoomProperties",ConstraintType.NEGATIVE_SOFT,20*$w,$ps));
>> end
>>
>> rule "meetsRoomPreference"
>>         when
>>                 $mr : MeetsRoomPreferenceConstraint($a :
>> admission, $r :
>> room);
>>                 $ps : PatientStay(admission == $a, bed.room
>> == $r);
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("meetsRoomPreference",ConstraintType.NEGATIVE_SOFT,8,$ps));
>> end
>>
>> rule "inGoodDepartment"
>>         when
>>                 $gd : GoodDepartmentConstraint($a :
>> admission, $d :
>> department);
>>                 $ps : PatientStay(admission == $a, $b :
>> bed,
>> eval($b.getRoom().getDepartment().equals($d)));
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("inGoodDepartment",ConstraintType.NEGATIVE_SOFT,10,$ps));
>> end
>>
>> rule "inGoodRoom"
>>         when
>>                 $gr : GoodRoomConstraint($a : admission, $r
>> : room, $w :
>> weight);
>>                 $ps : PatientStay(admission == $a, bed.room
>> == $r);
>>         then
>>                 insertLogical(new
>> IntConstraintOccurrence("inGoodRoom",ConstraintType.NEGATIVE_SOFT,10*$w,$ps));
>>
>> end
>>
>> rule "calcScore"
>> salience -10
>>         when
>>                 $count : Number() from accumulate(
>> IntConstraintOccurrence($w : weight) ,
>>
>>          sum($w) );
>>         then
>>
>> scoreCalculator.setScore(-$count.doubleValue());
>> end
>>
>> The classes with **Constraint in it are possible
>> combinations that cause a
>> constraint to be violated, and are calculated and inserted
>> at initialization
>> time (and are never changed). I know that the rule
>> "patientsToBeAssignedToRoomsOfAppropriateSex" is
>> fairly complex, but even
>> when I remove it, the performance is not fantastic. Is
>> there anything else I
>> can do to get better performance? I'm already using JDK
>> 1.6 and -server
>> mode. Furthermore, all classes used here have their default
>> equals and
>> hashCode methods, so they don't have an impact on
>> performance.
>>
>> Sincerely,
>>
>> Wim Vancroonenburg
>> _______________________________________________
>> rules-users mailing list
>> rules-users at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>
>
>
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