Hi. My environment: Win XP SP3, 2x2.13 GHz cpu, 3GB RAM, Drools 4.0.7, JDK 1.4.2_11, java compiler: JANINO, dialect: java. We have about 850 drl's with 5 - 10 conditions in each. 0 -2 evals in each. The drl's only contain one rule each. We are using Drools programatically by compiling the drls using PackageBuilder.addPackageFromDrl and adding them to a RuleBase using RuleBase.addPackage(PackageBuilder.getPackage()) When we are building our rule base we are never able to compile more than 1 -2 rules per second, which means we need over 10 minutes (at 100% cpu) to build our rulebase. Profiling shows 68% cpu time in org.drools.rule.builder.GroupElementBuilder.build and 18% cpu time in org.codehaus.janino.Compiler.compile. We have experimented by changing the compiler to ECLIPSE and the dialect to mvel but the results are the same. We have experimented using one PackageBuilder instance per drl or grouping drls by package and sharing a builder per package. Same result in both scenarios. We have also expermimented with compiling concurrently in serveral threads. Again, about the same result. My question is: Is this the performance we can expect from the compiler or are we doing something fundamentally wrong? Below is an example of one of our drls. This one contains no evals, but still takes more than 1 second to compile. If anyone can spot some issues with the way we are doing things the feedback would be much apreciated :) ------------------------------------ package domain.core.productoffer.rules.subscriptiontype import type.productoffer.ProductOfferRuleEvent import domain.core.subscription.Subscription import domain.core.subscription.SubscribedService import type.subscription.ActionTypeEnum import domain.core.productoffer.ProductOffer import domain.rules.RuleEvent global domain.core.productoffer.RuleValidationReport validationResult rule "RequiredVProducts" when ProductOfferRuleEvent(id == '3') ProductOffer(id.value == 31963) $subscription:Subscription() not ( SubscribedService(status != ActionTypeEnum.REMOVE_CANCEL && productId.value in (57, 69) ) from $subscription.getAllChildSubscribedServices()) then validationResult.addValidationMessage("2069", "For product offer rule event with id '3' and product offer with id=31963 subscription must have one of the following VProducts: 57, 69."); end ------------------------------------ Regards Christian Nedregård