[rules-users] How to avoid stateless session rule fire on every fact ?

[Wolfgang Laun]

On 07/08/2013, viraj <mayuraviraj at gmail.com> wrote:
> Hi all,
>
> In my project I have 20,000 rules to reason with 20,000 facts. The rules
> are
> embedded in facts. Therefore for each rule , there is one fact object which
> that rule belongs to. I'm using following condition to find this matching
> object.
>
> rule "Book Rule 1 - 187970786749253 "
> no-loop true
> when
> $book : Book( bookId == 187970786749253 , $eligible : eligible == false )
> UserProfile( userType == UserType.STUDENT ,  status == 1 ) //... other
> conditions
> then
> //Do something here...
> end

This very unusual. What is the point in defining one rule for each
book? Apparently these rules should reflect library procedures and I
can't imagine any library to need different processing for each book.
(There may be different processing per *category*, i.e., books that
can be taken out and books that can't etc.

Perhaps you describe the requirements of your application project.

>
> So above rule is belongs to Book object which has id = 187970786749253 (
> This is a unique id ). I'm using stateless sequential rule engine.
> Following is the my understanding how rules are executed over facts.
> For first rule it needs to check all the 20,000 objects in worst case to
> find matching Book. For second rule the worst case should be 19,999 object
> search since one object is found and processed. But I used
> AgendaEventListener to find the time for each rule. It has nearly constant
> time for each rule , which means for each rule, engine search all the
> 20,000
> object.

You can't measure the time required for the evaluation of a rule set
against a fact set by lisstening to agenda events. This will give you
the time required for the execution of the consequence (the then-part)
of a rule. You can measure the time required for inserting the 20000
facts, but I don't think that this will vary much, either.

-W

> I need to avoid this still keeping stateless session. Any ideas how
> to do this ?
>
> Thanks !
>
>
>
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