[rules-users] Re: Drools : usage as appointment booking engine ?
That makes a lot of sense. Metaheuristics and local search methods (which Drools Solver supports) are great for creating schedules, roster, plannings, ... . I've been using Drools Solver for a bed assignment problem in health care (more of a benchmark problem) and it performs well. Colleagues of mine are solving exam-timetables and course-timetables with metaheuristics, so these type of problems should be equally doable with Drools Solver. Drools Solver does not have any time "operators" like Nicolas says, that is something that your model should implement. Sincerely, Wim Vancroonenburg Greg Barton wrote: Well, Fusion is mainly geared towards processing incoming dynamic events. Drools-solver would be best for creating the appointment schedule. However, if you want to react to real time changes that may affect your schedule, you could always use drools-fusion for that. (i.e. we have an appointment for Bob, Alice, and Chuck in Room D on Monday. Then an event comes in saying Chuck is sick within 30 minues of the appointment. If Chuck is a critical member of the meeting the system decides to reschedule, but without the "only on Mondays" constraint.) So drools-solver would create the schedule, and drools-fusion would decide in real time based on the current schedule structure and the incoming events whether to respaawn a solver session to adjust the schedule. Does that make sense? --- On Thu, 5/7/09, Damien Raude-Morvan wrote: From: Damien Raude-Morvan Subject: Re: [rules-users] Drools : usage as appointment booking engine ? To: "Rules Users List" Date: Thursday, May 7, 2009, 10:50 AM Hello, Hi Nicolas, you should look at drools-solver here is a link to the documentation<http://hudson.jboss.org/hudson/job/drools/lastSuccessfulBuild/artifact/trunk/target/docs/drools-solver/html_single/index.html> Thanks this documentation, I was using oudated documentation from http://users.telenet.be/geoffrey/tmp/solver/manual/html_single/ . I've evaluated drools-solver, for example trying to evolve "lessonschedule" sample to include some time constraints but I failed to use time "operators" in drools solver. I found Drools Fusion time constraints (before, inside, meets) interesting but for now haven't been able to build something with it. Drools Fusion "StockTick" sample seems oriented to STREAM event and not to managing time slots and constraints on this time slots. Anybody having experience with such problems ? Regards, 2009/5/7 Damien Raude-Morvan Hi, I'm evaluating use of Drools 5 as an appointment booking engine. My input data are : - some time slots, defined with a start and end time. - some appointment constraints (only monday, only morning, appointment theorical duration) I've looked at Drools 5 Fusion without finding a way to go with this. Can someone give me some pointer / start URL about how to solve this kind of problems ? -- Damien Raude-Morvan / www.drazzib.com ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users ___ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
[rules-users] Re: Drools-solver performance optimizations?
I'll be sure to do those tests. However I don't know if I can publish these
results, since it is part of my thesis, but I imagine that Mr. Demeester
won't have any problem with sharing these results with you.
Sincerely,
Wim Vancroonenburg.
- Original Message -
From: "Geoffrey De Smet"
Newsgroups: gmane.comp.java.drools.user
To:
Sent: Saturday, February 14, 2009 10:12 AM
Subject: Re: Drools-solver performance optimizations?
I've worked at Kaho and I know Peter De Meester, his custom algorithms do
pretty well :)
I am really interested in how the different components measure up in
speed:
- calculating a single score (no doubt drools-solver will lose this one
due to the warmup time of drools)
- calculating 10.000 scores after calculating 10.000 scores to give
hotspot compiling some time to warm up. Each scores changes into the next
by a move (to allow score delta calculation).
- number of calculated scores per second and only start measuring after
100 seconds
- average number of moves per minute
- average number of moves per step
- average number of steps per minute
You'd do me a grand favor by publishing any results on this mailing list,
so we can find out where and how drools-solver needs improving.
Patches on drools-solver are always welcome of course too.
One thing that drools-solver currently lacks is build-in support for
rotating (phasing) through different local search solvers (first simulated
annealing, then tabu search, then great deluge, then start over). It
shouldn't be hard to implement that on top of drools-solver for now.
Also drools-solver currently only utilizes one CPU (it's single threaded).
Multi-thread support is coming. So you might want to take a look at how
the number of CPU's affect the other algorithms.
Anyway, first clean up your rules, tweak relativeSelection, use a starting
solution initializer, tweak other configuration, ...: that will make a big
difference. It's a game of perseverance - may the best algorithm win :)
With kind regards,
Geoffrey De Smet
Wim Vancroonenburg schreef:
Thanks to everybody for the tips. I will see what I can do with them to
squeeze out that last bit of performance.
To Geoffrey:
I just wanted to let you know that I'm the thesis student from KAHOSL
that is using Drools Solver for the Patient Admission Scheduling-problem.
The performance of Drools Solver isn't bad, but I'm trying to match my
promotor's code. His code is substantialy faster at the moment (a
hyperheuristic implementation). So I'm trying to squeeze out every bit of
performance. Thanks for the tips and the quick response by the way.
Sincerely,
Wim Vancroonenburg.
- Original Message - From: "Geoffrey De Smet"
Newsgroups: gmane.comp.java.drools.user
To:
Sent: Friday, February 13, 2009 3:32 PM
Subject: Re: Drools-solver performance optimizations?
Take a look at some of the tricks in the ITC2007 examination example:
- 0.002 Real-world problems are
so big that you can't evaluate all moves for every step. You need to
take a random percentage (for example 0.2%) of all moves to evaluate.
If you aren't using this, use it and you should see a big difference.
Once you're a 100% confident in your score function, use the benchmarker
to determine the perfect relativeSelection.
- I calculate a TopicConflict list before starting the solver and use it
in my score drl, because none of the move change the result of that
calculation - and it's used a lot.
- avoid backwards chaining functions when possible, like accumulate,
exists, collect, ... Forward chaining = free score delta calculation.
- Use the most limiting facts first, so
$room : Room(sexRestriction == Sex.Dependent && capacity > 1);
before
$n : Night();
Most of your rules look good. I do recommend turning them off one by one
to see if none outclasses all others in CPU consumption, so you know
which one to put your time into.
I would rewrite the patientsToBeAssignedToRoomsOfAppropriateSex as such
rule "patientsToBeAssignedToRoomsOfAppropriateSex"
when
$room : Room(sexRestriction == Sex.Dependent && capacity
> 1);
ps1 : PatientStay(bed.room == $room, n : night, $leftId
: id, g : patient.admission.sex)
ps2 : PatientStay(bed.room == $room, night == $n,
patient.admission.sex != $g, id > $leftId)
then
insertLogical(new
IntConstraintOccurrence("patientsToBeAssignedToRoomsOfAppropriateSex",ConstraintType.NEGATIVE_HARD,
50, $ps1, $ps2));
end
I do the id thing because otherwise it would match twice, once for A and
B and once for B and A
PS: be carefull with "PatientStay(bed.room == ...), IIRC it gets MVEL'ed
(= a bit performance loss) or flattening is a problem because the move
only does an update(PatientStay)
[rules-users] Re: Drools-solver performance optimizations?
Thanks to everybody for the tips. I will see what I can do with them to
squeeze out that last bit of performance.
To Geoffrey:
I just wanted to let you know that I'm the thesis student from KAHOSL that
is using Drools Solver for the Patient Admission Scheduling-problem. The
performance of Drools Solver isn't bad, but I'm trying to match my
promotor's code. His code is substantialy faster at the moment (a
hyperheuristic implementation). So I'm trying to squeeze out every bit of
performance. Thanks for the tips and the quick response by the way.
Sincerely,
Wim Vancroonenburg.
- Original Message -
From: "Geoffrey De Smet"
Newsgroups: gmane.comp.java.drools.user
To:
Sent: Friday, February 13, 2009 3:32 PM
Subject: Re: Drools-solver performance optimizations?
Take a look at some of the tricks in the ITC2007 examination example:
- 0.002 Real-world problems are so
big that you can't evaluate all moves for every step. You need to take a
random percentage (for example 0.2%) of all moves to evaluate.
If you aren't using this, use it and you should see a big difference.
Once you're a 100% confident in your score function, use the benchmarker
to determine the perfect relativeSelection.
- I calculate a TopicConflict list before starting the solver and use it
in my score drl, because none of the move change the result of that
calculation - and it's used a lot.
- avoid backwards chaining functions when possible, like accumulate,
exists, collect, ... Forward chaining = free score delta calculation.
- Use the most limiting facts first, so
$room : Room(sexRestriction == Sex.Dependent && capacity > 1);
before
$n : Night();
Most of your rules look good. I do recommend turning them off one by one
to see if none outclasses all others in CPU consumption, so you know which
one to put your time into.
I would rewrite the patientsToBeAssignedToRoomsOfAppropriateSex as such
rule "patientsToBeAssignedToRoomsOfAppropriateSex"
when
$room : Room(sexRestriction == Sex.Dependent && capacity >
1);
ps1 : PatientStay(bed.room == $room, n : night, $leftId :
id, g : patient.admission.sex)
ps2 : PatientStay(bed.room == $room, night == $n,
patient.admission.sex != $g, id > $leftId)
then
insertLogical(new
IntConstraintOccurrence("patientsToBeAssignedToRoomsOfAppropriateSex",ConstraintType.NEGATIVE_HARD,
50, $ps1, $ps2));
end
I do the id thing because otherwise it would match twice, once for A and B
and once for B and A
PS: be carefull with "PatientStay(bed.room == ...), IIRC it gets MVEL'ed
(= a bit performance loss) or flattening is a problem because the move
only does an update(PatientStay) (=> score gets corrupted on second
calculation)
PatientStay(room == ...) with PatiantStay.getRoom(){return
getBed().getRoom()) isn't dangerous
Mark or Edson could probably answer this question.
With kind regards,
Geoffrey De Smet
Wim Vancroonenburg schreef:
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.NEGAT
[rules-users] Re: Drools-solver performance optimizations?
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"
Newsgroups: gmane.comp.java.drools.user
To: "Rules Users List"
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 wrote:
From: Wim Vancroonenburg
Subject: [rules-users] Drools-solver performance optimizations?
To: rules-users@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
[rules-users] Drools-solver performance optimizations?
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@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
