Hello, Has anyone had to resolve out of memory errors with large applications using moderatly sized rulebases? Increasing the permGen any higher does not appear to be an option for us. DROOLS Version 4.01 OutOfMemory Error in PermGen space. Our application has ~5000 classes and uses ~3500 rules. Each rules has on average 3 conditions and 2 actions. The application uses multiple drools rules engines and we load multiple rulebases into memory. Would we have a small memory footprint if we combine all of our rules into a single rulebase and use agenda filtration to execute the appropriate rules? Right now it is cleaner for us to separate the rulebases. Current settings- WAS 6.1 on Solaris Max Heap 2560 Max PermGen 1024 WAS 6.1 throws startup errors if we increase the Max PermGen above 1024, so we are looking for alternative solutions. This seems like a lot of memory for permGen anyway. Asides: We do not use WorkingMemoryFileLogger We have tried using a newer Janino jar but we still encounter the OutOfMemoryError. When we have the rules engine running it is extremely fast and we are very pleased with being able to create our rules in Decision Table format. If you have any suggestions for the above issue that would be great. What would you estimate the permGen usage would be on a 3500 rule RuleBase alone? -- View this message in context: http://www.nabble.com/OutOfMemory-Error---3500-Rules-tp17019001p17019001.... Sent from the drools - user mailing list archive at Nabble.com.