[rules-users] Request for assistance in removing eval from a rule

[Edson Tirelli]

   David,

   Eval is really bad for perf, but still, sometimes it is the only way to
do things like call methods. So, in your case, it all depends on what
"containsKeywordString()" method is doing?

   Also, is RulesUtil just a utility class? I mean with no data you reason
over? if so, I strongly advise you to make it a global, instead of matching
it in the rule like a fact.

   Regarding evals, inline evals are just a bit lighter than top level
evals, but there is an important difference:

* inline evals MUST be time consistent, i.e., they must evaluate to the same
value everytime they are called.
* top level evals can deal with changes appropriately

    []s
    Edson

2008/9/15 Warren, David [USA] <warren_david at bah.com>

>  Folks -
>
> After seeing the thread on evals hurting performance a couple of weeks ago,
> I tried to remove them from a rule set we are using (running Drools 4.0.4),
> and have had limited success.
>
> An example is shown below.  We're using evals every time we make a call to
> "rulesUtil", a helper class we have for checking strings for keywords.  Two
> questions:
>
> 1. Does using inline evals (like below) hurt performance as much as using
> non-inline evals?
> 2. If so, any thoughts for how to rewrite this rule to avoid using the
> eval?
>
>
> rule
> 'my rule'
> *salience* 790
> *activation-group* "priorityRule"
> *when*
> ruleUtil : RulesUtil( )
> s1 : Sensor( source == "X, $rfp : RFP , *eval*(
> ruleUtil.containsKeywordString($rfp, "Y" )) , $tcn : TCN)
> s2 : Sensor( TCN != $tcn, source == "Z"
> *then*
> System.out.println("my rule");
> priority.setPriorityName("A");
>
> end
>
> Thanks,
> David Warren
>
>  ------------------------------
> *From:* rules-users-bounces at lists.jboss.org [mailto:
> rules-users-bounces at lists.jboss.org] *On Behalf Of *Edson Tirelli
> *Sent:* Friday, September 05, 2008 2:59 PM
> *To:* Rules Users List
> *Subject:* Re: [rules-users] Drools, Performance issues on 4.0.7 Vs 2.5
>
>
>    Start by eliminating the evals and writing your constraints properly
> inside the patterns. Drools 3+ is orders of magnitude faster than Drools
> 2.x, but you need to leverage its power in your rules. Please read the
> manual as the version 3 was a completely rewrite of version 2. Version 4 is
> an improvement over 3.
>
>    As an example, look at this:
> http://blog.athico.com/2006/11/rush-hour-and-content-based-routing.html
>
>    []s
>    Edson
>
> 2008/9/5 Rout, Sushanta (ThoughtMill) <Sushanta.Rout at ihg.com>
>
>> We were using Drools 2.5 version earlier. Now we have switched to drools
>> 4.0.7. But we see significant issues with performance like drools 4.0.7
>> is three times slower than 2.5 . Has anybody encountered the issue?
>>
>> Here is a sample of the rule, we have some more similar to this.
>> rule "test"
>>        dialect "java"
>>        activation-group "group1"
>>        when
>>                $croNumberDetailsRequest : CRONumberDetailsRequest()
>>                $resdirectPhoneNumber : ResdirectPhoneNumber()
>>                eval($resdirectPhoneNumber.getType().getId() == 5 &&
>>
>> $resdirectPhoneNumber.isValidForBrand($croNumberDetailsRequest.getBrand(
>> )) &&
>>                         $croNumberDetailsRequest.getRegion() != null &&
>>
>> $resdirectPhoneNumber.isValidRegion($croNumberDetailsRequest.getRegion()
>> ) &&
>>                         $croNumberDetailsRequest.getLocale() != null &&
>>
>>
>> $resdirectPhoneNumber.isValidForLocaleId($croNumberDetailsRequest.getLoc
>> ale()) &&
>>
>> $resdirectPhoneNumber.isValidSlot($croNumberDetailsRequest.getSlot()));
>>
>>        then
>>                ResultList.add($resdirectPhoneNumber);
>> end
>>
>> _______________________________________________
>> rules-users mailing list
>> rules-users at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>
>
>
> --
> Edson Tirelli
> JBoss Drools Core Development
> JBoss, a division of Red Hat @ www.jboss.com
>
> _______________________________________________
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> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>


-- 
Edson Tirelli
JBoss Drools Core Development
JBoss, a division of Red Hat @ www.jboss.com
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