[rules-users] optimization on a lot of simple rules
Greg Barton
greg_barton at yahoo.com
Tue Jul 21 00:15:28 EDT 2009
Well, if your rules are going to be that simple, have you tried sequential mode? If there's never any reaction to working memory changes you don't need the rete network. You should get much better performance out of that ruleset, and others like it, in sequential mode.
See http://downloads.jboss.com/drools/docs/5.0.1.26597.FINAL/drools-expert/html_single/index.html, section "3.3.7.1. Sequential Mode"
In a nutshell, the rete network is used for tracking and reacting to changes in the objects inserted into working memory. (i.e. a rule fires, changes a WM object, then other rules may be eligible to fire based on that change.) If you're not going to be using that functionality you'd be constructing and maintaining the rete for no reason.
--- On Mon, 7/20/09, nesta <nesta.fdb at 163.com> wrote:
> From: nesta <nesta.fdb at 163.com>
> Subject: Re: [rules-users] optimization on a lot of simple rules
> To: rules-users at lists.jboss.org
> Date: Monday, July 20, 2009, 10:13 PM
>
> I execute above test codes, with 100 rules running 1000
> times. In the same
> time, I profile the test codes.
> http://www.nabble.com/file/p24581025/profile.jpg
> The profile result shows that some methods execute 100,000
> times.
> In test codes,
> Service has two states, 0 or 1.
> Subscriber has two states, 0 or 1.
>
> inserted facts:
> Product product = new Product(1, 1);
> Service service = new Service(1);
> Subscriber subscriber = new Subscriber(1);
>
> Service matches a half of total rules, namely 50. So is
> Subscriber.
> (50 + 50 ) * 1000 (running times) = 100,000
>
> I am confused what drools does. Is there a way to optimize
> it?
>
>
> Greg Barton wrote:
> >
> >
> > 1) Yes, if you eliminate joins in rules, you will have
> no joins in the
> > rete. This is self evident.
> >
> > 2) The way you have the rules structured, there is no
> relationship between
> > the joined objects. This will cause what's
> called a "cartesian join"
> > where all combinations of all instances of each object
> type are
> > instantiated. This can be very expensive, memory
> and CPU wise. You've
> > stated that there are only one instance of each object
> type in working
> > memory, but are you absolutely sure of that?
> Cartesian joins can easily
> > cause performance problems quite quickly.
> >
> > For instance, say you've got these objects in working
> memory:
> >
> > Subscriber(gender="male")
> > Subscriber(gender="female")
> > Service(name="ftp")
> > Service(name="http")
> > Product(id=1)
> > Product(id=2)
> > Product(id=3)
> >
> > After inserting a Decision into working memory, the
> rule will fire 2*2*3
> > times. (#Subscribers * #Services * #Products)
> This is by design. Is this
> > what you want?
> >
> > 3) Do you really need the 'Subscriber(gender == "male"
> or "female")' term?
> > Why not just 'Subscriber()'? Are you classifying
> transgendered or
> > nonhuman subscribers in your system?
> >
> > --- On Mon, 7/20/09, nesta <nesta.fdb at 163.com>
> wrote:
> >
> >> From: nesta <nesta.fdb at 163.com>
> >> Subject: Re: [rules-users] optimization on a lot
> of simple rules
> >> To: rules-users at lists.jboss.org
> >> Date: Monday, July 20, 2009, 10:22 AM
> >>
> >> I want to test the matching performance of drools.
> As I
> >> mentioned that there
> >> are a lot of rules and the rule is like:
> >> rule 1
> >> when
> >> Decision()
> >> Subscriber(gender ==
> >> "male" or "female")
> >> Service(name ==
> >> "ftp" or "http")
> >> Product(id == 1)
> >> ......
> >> then
> >> end
> >>
> >> After test, more condition elements under when,
> more time
> >> needs to execute
> >> the test.
> >> for example
> >> Location ( location == "home" or "office")
> >> and so on.
> >> So I worry about the matching performance with
> drools.
> >>
> >> I found that a lot of JoinNodes would be executed
> in
> >> runtime. I mean if
> >> there is 1000 rules, there will be a lot of
> JoinNodes
> >> (There are at least
> >> 1000 JoinNodes between Decision and Product ). And
> it
> >> exactly affects the
> >> execution performance.
> >>
> >> As you know, Decision, Product, Servcie and so on
> are plan
> >> Java classes. If
> >> I define all of attributes of above classes in one
> class
> >> named WholeFact,
> >> only one Java Type, there is no mentioned issue.
> >>
> >> With WholeFact class, the rule will be changed as
> follows:
> >> rule 1
> >> when
> >> WholeFact(
> >> subscriberGender == "male" or "female",
> >>
> >> serviceName
> >> == "ftp" or "http",
> >>
> >>
> >> productId == 1 or 2 or 3 ...
> >> )
> >> then
> >> end
> >>
> >>
> >> Greg Barton wrote:
> >> >
> >> >
> >> > Now this finally rises to something that
> needs rules.
> >> :) In all of the
> >> > previous examples you've given you could just
> have a
> >> > Map<ProductKey,Handler> where the
> Handler looks
> >> like this:
> >> >
> >> > interface Handler {
> >> > void handle(Product product, Decision
> >> decision);
> >> > }
> >> >
> >> > ...and the ProductKey consists of properties
> that
> >> uniquely identify how
> >> > the Product is handled. So, on it's own,
> that
> >> functionality did not
> >> > require rules.
> >> >
> >> > However, now that you've introduced more
> complex
> >> decisions, with varying
> >> > data, to affect the Decision for each
> Property type,
> >> rules are more
> >> > appropriate.
> >> >
> >> > Is there any reason why you only have one of
> each
> >> object type in memory at
> >> > one time? Maybe if you state more of the
> problem
> >> requirements we can help
> >> > you better.
> >> >
> >> > --- On Mon, 7/20/09, nesta <nesta.fdb at 163.com>
> >> wrote:
> >> >
> >> >> From: nesta <nesta.fdb at 163.com>
> >> >> Subject: Re: [rules-users] optimization
> on a lot
> >> of simple rules
> >> >> To: rules-users at lists.jboss.org
> >> >> Date: Monday, July 20, 2009, 4:14 AM
> >> >>
> >> >> Thanks very much.
> >> >> But if for every rule, there is one
> algorithm or
> >> discount
> >> >> which means that
> >> >> result has nothing related with Product's
> id and
> >> usage. I
> >> >> can't merge all
> >> >> rules in one rule. At the same time,
> besides
> >> Product and
> >> >> Decision fact type,
> >> >> there are more fact types.
> >> >> For example:
> >> >> rule 1
> >> >> when
> >> >> Decision()
> >> >> Subscriber(gender ==
> >> >> "male" or "female")
> >> >> Service(name ==
> >> >> "ftp" or "http")
> >> >> Product(id == 1)
> >> >> ......
> >> >> then
> >> >> ......
> >> >> end
> >> >> rule 2
> >> >> when
> >> >> Decision()
> >> >> Subscriber(gender ==
> >> >> "male" or "female")
> >> >> Service(name ==
> >> >> "ftp" or "http")
> >> >> Product(id == 2)
> >> >> ......
> >> >> then
> >> >> ......
> >> >> end
> >> >>
> >> >> .....
> >> >> .....
> >> >>
> >> >> In this scenario, if there are 1000
> rules, there
> >> will
> >> >> be a lot of JoinNode.
> >> >> But in runtime, there is only one
> Decision
> >> instance, one
> >> >> Subscriber instance
> >> >> and Service instance.
> >> >>
> >> >> If I define all data in one fact type, I
> think
> >> that there
> >> >> are not a lot of
> >> >> JoinNodes.
> >> >>
> >> >> Is there any other method?
> >> >>
> >> >>
> >> >>
> >> >> Wolfgang Laun-2 wrote:
> >> >> >
> >> >> > Well, what is the realtion between
> id, usage
> >> and the
> >> >> result that's to be
> >> >> > stored in a Decision or a global?
> >> >> >
> >> >> > Typically, such rules could be
> written as
> >> >> >
> >> >> > rule x
> >> >> > no-loop true
> >> >> > when
> >> >> > $d : Decision()
> >> >> > $p :Product( id == 1, $usage
> :
> >> >> usage )
> >> >> > then
> >> >> > compute/store value,
> depending
> >> >> on the formula for id == 1 (using
> >> >> > usage)
> >> >> > end
> >> >> > // similar rule for id == 2,3,...
> >> >> >
> >> >> > If value is a straightforward
> function of id
> >> (and
> >> >> usage), then implement a
> >> >> > function compValue and use a single
> rule,
> >> e.g.:
> >> >> >
> >> >> > rule x
> >> >> > no-loop true
> >> >> > when
> >> >> > $d : Decision()
> >> >> > Product( $id : id, $usage :
> >> >> usage)
> >> >> > then
> >> >> > modify $d value to compValue(
> $id,
> >> $usage
> >> >> )
> >> >> >
> >> >> > Distinguishing all individual
> combinations of
> >> id and
> >> >> usage on the LHS
> >> >> > seems
> >> >> > excessive.
> >> >> >
> >> >> > The ordering of CEs also affects
> execution
> >> times.
> >> >> >
> >> >> > -W
> >> >> >
> >> >> > On 7/20/09, nesta <nesta.fdb at 163.com>
> >> >> wrote:
> >> >> >>
> >> >> >>
> >> >> >> In this scenario, there are
> 1000
> >> products,
> >> >> different product has
> >> >> >> different
> >> >> >> price, besides this, the price
> is
> >> affected by
> >> >> usage. I want to use
> >> >> >> Product.id to match the rules.
> >> >> >>
> >> >> >> As you mentioned "The crude
> duplication
> >> of rules
> >> >> where only the constant
> >> >> >> to
> >> >> >> be matched with
> >> >> >> Product.id varies can, most
> likely, be
> >> avoided."
> >> >> >>
> >> >> >> How to avoid it in this
> scenario?
> >> >> >>
> >> >> >>
> >> >> >> Wolfgang Laun-2 wrote:
> >> >> >> >
> >> >> >> > It's difficult to suggest
> an
> >> optimized form
> >> >> for your rules 1-infinity,
> >> >> >> > since
> >> >> >> > we do not know what you
> want to
> >> achieve.
> >> >> >> >
> >> >> >> > The crude duplication of
> rules where
> >> only the
> >> >> constant to be matched
> >> >> >> with
> >> >> >> > Product.id varies can, most
> likely,
> >> be
> >> >> avoided.
> >> >> >> >
> >> >> >> > -W
> >> >> >> >
> >> >> >> >
> >> >> >> >
> >> >> >> > On Sun, Jul 19, 2009 at
> 3:15 PM,
> >> nesta <nesta.fdb at 163.com>
> >> >> wrote:
> >> >> >> >
> >> >> >> >>
> >> >> >> >> Hi,
> >> >> >> >>
> >> >> >> >> I am a newbie in
> drools. There
> >> are a lot
> >> >> of simple rules in a
> >> >> >> scenario.
> >> >> >> >> For example
> >> >> >> >> rule 1
> >> >> >> >> when
> >> >> >> >> Product( id
> >> >> ==1, usage == 1)
> >> >> >> >> $decision :
> >> >> Decision()
> >> >> >> >> then
> >> >> >> >>
> >> >> $decision.setValue(1);
> >> >> >> >> end
> >> >> >> >>
> >> >> >> >> rule 2
> >> >> >> >> when Product( id ==2,
> usage ==
> >> 1)
> >> >> >> >> $decision :
> Decision()
> >> >> >> >> rule 3
> >> >> >> >> when Product( id ==3,
> usage ==
> >> 1)
> >> >> >> >> $decision :
> Decision()
> >> >> >> >> rule 4
> >> >> >> >> when Product( id ==4,
> usage ==
> >> 1)
> >> >> >> >> $decision :
> Decision()
> >> >> >> >> rule 5
> >> >> >> >> when Product( id ==5,
> usage ==
> >> 1)
> >> >> >> >> $decision :
> Decision()
> >> >> >> >> ......
> >> >> >> >>
> >> >> >> >> I have a Product fact
> whose id =
> >> 5 and
> >> >> usage = 1, in my first
> >> >> >> thinking,
> >> >> >> >> only
> >> >> >> >> rule 5 is matched,
> there should
> >> be not
> >> >> much more different between 1
> >> >> >> rule
> >> >> >> >> and a lot of rules in
> runtime.
> >> >> >> >>
> >> >> >> >> But the result shows
> that they
> >> are
> >> >> different. More rules will cost
> >> >> >> more
> >> >> >> >> time. If there are 1
> thousand
> >> rules, some
> >> >> Node and Sink will execute 1
> >> >> >> >> thousand times.
> >> >> >> >>
> >> >> >> >> My question is how to
> optimize
> >> this
> >> >> scenario?
> >> >> >> >> --
> >> >> >> >> View this message in
> context:
> >> >> >> >>
> >> >> >>
> >> >>
> >> http://www.nabble.com/optimization-on-a-lot-of-simple-rules-tp24556724p24556724.html
> >> >> >> >> Sent from the drools -
> user
> >> mailing list
> >> >> archive at Nabble.com.
> >> >> >> >>
> >> >> >> >>
> >> >>
> _______________________________________________
> >> >> >> >> 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
> >> >> >> >
> >> >> >> >
> >> >> >>
> >> >> >> --
> >> >> >> View this message in context:
> >> >> >>
> >> >>
> >> http://www.nabble.com/optimization-on-a-lot-of-simple-rules-tp24556724p24563725.html
> >> >> >> Sent from the drools - user
> mailing list
> >> archive
> >> >> at Nabble.com.
> >> >> >>
> >> >> >>
> >> _______________________________________________
> >> >> >> 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
> >> >> >
> >> >> >
> >> >>
> >> >> --
> >> >> View this message in context:
> >> >>
> >> http://www.nabble.com/optimization-on-a-lot-of-simple-rules-tp24556724p24566350.html
> >> >> Sent from the drools - user mailing list
> archive
> >> at
> >> >> Nabble.com.
> >> >>
> >> >>
> _______________________________________________
> >> >> 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
> >> >
> >> >
> >>
> >> --
> >> View this message in context:
> >> http://www.nabble.com/optimization-on-a-lot-of-simple-rules-tp24556724p24571875.html
> >> Sent from the drools - user mailing list archive
> at
> >> Nabble.com.
> >>
> >>
> >> _______________________________________________
> >> 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
> >
> >
>
> --
> View this message in context: http://www.nabble.com/optimization-on-a-lot-of-simple-rules-tp24556724p24581025.html
> Sent from the drools - user mailing list archive at
> Nabble.com.
>
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
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