Hi Wolfgang, Ok, well I implemented my "option #2", which has cut it down to 23ms, which is a good start. My timing is done by taking the time before, and after, and dividing by the number of claims processed. (and averaging over a few runs) I use one thread per StatefulKnowledgeSession... My machine has 2 cores, but it will eventually be running on an 8 core beast, so i reckon this was a good improvement. I was just worried that I wouldn't be able to simultaneously process multiple K-Sessions, but apparently, Drools doesn't mind. I'm pretty sure any machine with multiple cores supports parallel java threads, no? ----- Regarding my Utilities method, eg. isWithinTimePeriod("20100308", "20090405", 1, "Y") I can get about 5ms off by commenting out the eval, so it's not going to be a big jump even if I fix it, but, well, I am using yyyyMMdd Strings, which in the method, I sub-stringed, converted to ints, instantiated DateMidnight objects, and compared using Joda-time daysBetween/monthsBetween/yearsBetween methods. My thought was that pre-converting to ints would help, so that each ClaimLine has year/month/day int variables, and pass them in instead. (i.e., Saves 3 String.substring()'s, and 3 Integer.parseInt()). but that actually slowed it down a few milliseconds. (Maybe passing 6 params instead of 2?!) I'm comparing two dates by an arbitrary period, like "2 days" or "1 month", and need the framework of the Gregorian Calendar. So, I don't think I can do anything about this. 2 months is never guaranteed to be a set number of milliseconds. It all depends on the claim date, which is fact data, and therefore variable. Regards, Daniel -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/Parallelization-tp809... Sent from the Drools - User mailing list archive at Nabble.com.

I'm not a guru but I'm pretty certain all modern JVMs support multiple cores well. You will probably make sure you are using the server VM (-server) and not the client VM (assuming you are using the standard VM). Depending on what you current machine is and whether or not you have 2 cpu's or just two cores (and if java can tell the difference) you may or may not currently be running the server vm (see http://java.sun.com/javase/6/docs/technotes/guides/vm/server-class.html) If you aren't then you may be very lucky and find that switching to the server class vm gives you those few extra ms to keep your boss happy. Presumably you have also done the other standard optimization tricks to ensure you have sufficient heap memory etc? Thomas From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Wolfgang Laun Sent: 11 May 2010 14:32 To: Rules Users List Subject: Re: [rules-users] Parallelization On Tue, May 11, 2010 at 2:55 PM, djb <dbrownell83@hotmail.com<mailto:dbrownell83@hotmail.com>> wrote: Hi Wolfgang, I use one thread per StatefulKnowledgeSession... My machine has 2 cores, but it will eventually be running on an 8 core beast, so i reckon this was a good improvement. I was just worried that I wouldn't be able to simultaneously process multiple K-Sessions, but apparently, Drools doesn't mind. I'm pretty sure any machine with multiple cores supports parallel java threads, no? This is a Q for a Java guru (which I'm not), and may depend on the JVM and what not. Care to provide details? Probably there's people on this list who might know. (Otherwise, I have a good contact.) ----- Regarding my Utilities method, eg. isWithinTimePeriod("20100308", "20090405", 1, "Y") I can get about 5ms off by commenting out the eval, so it's not going to be a big jump even if I fix it, but, well, I am using yyyyMMdd Strings, which in the method, I sub-stringed, converted to ints, instantiated DateMidnight objects, and compared using Joda-time daysBetween/monthsBetween/yearsBetween methods. My thought was that pre-converting to ints would help, so that each ClaimLine has year/month/day int variables, and pass them in instead. (i.e., Saves 3 String.substring()'s, and 3 Integer.parseInt()). but that actually slowed it down a few milliseconds. (Maybe passing 6 params instead of 2?!) You can treat 20100510 as an integer defining one date; all relations between such numbers would hold as for the "true" dates - you just can't compute durations (days between dates) by simple substraction. I'm comparing two dates by an arbitrary period, like "2 days" or "1 month", and need the framework of the Gregorian Calendar. So, I don't think I can do anything about this. 2 months is never guaranteed to be a set number of milliseconds. It all depends on the claim date, which is fact data, and therefore variable. I'm not sure how the other arguments in the call ("Y", 99) are related to rules or facts, but a repeated test whether one date dx is between d1 and d2 where d2 depends on d1 and a duration would certainly gain from computing d2 once. -W ________________________________ ************************************************************************************** This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster(a)nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary. NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00 **************************************************************************************

On 11/05/2010 13:55, djb wrote: multiple ksessions running in different threads all sharing the same kbase is perfectively acceptable, it was designed that way. Mark

If you're using the sun VM multiple Threads will use multiple cores just fine. What version of java? Are you intending to max out the CPU on the machine? If so I suggest this configuration, for an 8 core box: 7 Threads, each running a StatefulKnowledgeSession. Concurrent garbage collection, with VM startup parameters like this: -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:MaxGCPauseMillis=150 -XX:+CMSIncrementalMode -XX:+CMSIncrementalPacing -XX:+UseCMSCompactAtFullCollection -XX:CMSFullGCsBeforeCompaction=2 Here's a good reference for GC parameters: http://java.sun.com/javase/technologies/hotspot/gc/gc_tuning_6.html And if you're feeling frisky, try out these to see if it improves performance: -XX:+UseTLAB -XX:+UseSpinning -XX:+UseFastAccessorMethods The default recommendation for maxing out the CPU is to use <num_cores>+1 Threads, but in this case since garbage collection may be an issue I'd reduce that by two. You need one core "dedicated" to other stuff (I/O and whatnot) and some resources for GC. --- On Tue, 5/11/10, djb <dbrownell83(a)hotmail.com&gt; wrote: