Re: [rules-users] Multithreading work items

The problem is the multithreading execution. For a "SPLIT NODE" of type "AND", first, is process one branch, after, the next branch and so on for each. The execution is sequential. PEDRO MARIA BUITRAGO MANTILLA Bogotá, Colombia 2010/4/26 rudolf michael <roudolf(a)gmail.com&gt; Alan, couldn't you have achieved this using a Split and Join? > > 2010/4/26 <Alan.Gairey(a)tessella.com&gt; > > >> Interesting. What you've described Pedro is similar to what I'm trying to >> achieve, and also relates to some earlier posts I made to the list (title: >> 'Drools Flow: Problem with constraint in (Wait) State node'). >> >> I have a process that launches independent sub flows; these independent >> sub flows execute on separate threads. I then want the original process to >> "block" until all the subflows have finished, and to then continue. >> In order to achieve this, I've done the following: >> >> - Each process (both the main flow and each sub flow) is executed by a >> separate stateful knowledge session. >> - When a sub flow is started, it inserts a fact into the working memory >> of the session for the original process. >> - When a sub flow finishes, it updates a fact in the working memory of >> the session for the original process to "signal" its completion. >> - After launching the sub flows, the original process contains a (wait) >> state node; the constraint for this node is designed to block until all >> facts in its memory are in the "signalled" state. >> >> I've attached an example project that illustrates what I'm trying to >> achieve. The constraint on the wait state node is currently as follows: >> >> (and forall(SimpleFact(complete == true)) exists(SimpleFact())) >> >> I'd be interested to know from someone who understands rule syntax better >> than me as to why this seems to work when other attempts (see my earlier >> posts) failed. >> >> I still have two problems though: >> >> 1) The above constraint appeared to work OK with an earlier 5.1 snapshot >> build (from a couple of months back). However, using the latest successful >> build from trunk (#3845), the Action node after the wait state node isn't >> executed. Given that 5.1.M2 is supposed to be imminent, I'm worried. Does >> anyone know why this no longer works? >> >> 2) If I try to enable JPA-based state persistence, using the Bitronix >> transaction manager, then when I try to insert a fact into the working >> memory of the session for the original process from a separate thread, I get >> the following error: >> >> bitronix.tm.internal.BitronixRollbackException: transaction was marked as >> rollback only and has been rolled back >> at >> bitronix.tm.BitronixTransaction.commit(BitronixTransaction.java:153) >> at >> bitronix.tm.BitronixTransactionManager.commit(BitronixTransactionManager.java:96) >> at >> org.drools.persistence.session.SingleSessionCommandService.execute(SingleSessionCommandService.java:258) >> at >> org.drools.command.impl.CommandBasedStatefulKnowledgeSession.insert(CommandBasedStatefulKnowledgeSession.java:306) >> at >> com.test.InsertWorkItemHandler$1.insertFact(InsertWorkItemHandler.java:52) >> at >> com.test.InsertWorkItemHandler$1.run(InsertWorkItemHandler.java:40) >> at java.lang.Thread.run(Thread.java:619) >> java.lang.RuntimeException: Could not rollback transaction >> at >> org.drools.persistence.session.SingleSessionCommandService.execute(SingleSessionCommandService.java:283) >> at >> org.drools.command.impl.CommandBasedStatefulKnowledgeSession.insert(CommandBasedStatefulKnowledgeSession.java:306) >> at >> com.test.InsertWorkItemHandler$1.insertFact(InsertWorkItemHandler.java:52) >> at >> com.test.InsertWorkItemHandler$1.run(InsertWorkItemHandler.java:40) >> at java.lang.Thread.run(Thread.java:619) >> Caused by: java.lang.IllegalStateException: no transaction started on >> this thread >> at >> bitronix.tm.BitronixTransactionManager.rollback(BitronixTransactionManager.java:103) >> at >> org.drools.persistence.session.SingleSessionCommandService.execute(SingleSessionCommandService.java:278) >> ... 4 more >> >> Any help anyone can provide would be very much appreciated. Thank you. >> >> Regards, >> >> Alan >> >> >> >> >> *Pedro Maria Buitrago Mantilla <pmbtgun(a)gmail.com&gt;* >> Sent by: rules-users-bounces(a)lists.jboss.org >> >> 23/04/2010 14:38 >> Please respond to >> Rules Users List <rules-users(a)lists.jboss.org&gt; >> >> To >> Rules Users List <rules-users(a)lists.jboss.org&gt; >> cc >> Subject >> Re: [rules-users] Multithreading work items >> >> >> >> >> Each of the sub flows requires final user design. Mauricio thanks very >> much. >> >> PEDRO BUITRAGO >> Bogotá, Colombia >> >> >> 2010/4/22 Mauricio Salatino <*salaboy(a)gmail.com* <salaboy(a)gmail.com&gt;&gt; >> yes.. sounds more like a normal java problem than Drools FLow problem. I >> think that your solution is the correct one because it handle internally the >> multithreaded requierements and then it continue the business process >> normally. >> >> >> 2010/4/22 Pedro Maria Buitrago Mantilla <*pmbtgun@gmail.com*&lt;pmbtgun(a)gmail.com&gt;&gt; >> >> >> The idea is to run multiple independent sub flows. Each of the sub flows >> requires approximately 2 minutes to complete, so parallel processing is >> required. Once all the sub flows have completed their tasks is necessary to >> collect all the results and process them. This implies that the workflow >> should not end until it collects all information submitted by the sub flows. >> >> For now, I think to create, with JMS, a queue in jboss receive the name >> of each sub flow, create your own KnowledgeBase run each subflow as a >> separate workflow and delivers the results. Finally, some components will >> take all the results (from a database of another jms queue and process and >> again another component start another workflow to process all results. >> >> >> PEDRO BUITRAGO >> Bogotá, Colombia >> >> >> 2010/4/22 Mauricio Salatino <*salaboy(a)gmail.com* <salaboy(a)gmail.com&gt;&gt; >> >> can you describe a little bit your use case? >> I'm not sure about what you want to achieve. >> >> 2010/4/21 Pedro Maria Buitrago Mantilla <*pmbtgun@gmail.com*&lt;pmbtgun(a)gmail.com&gt; >> > >> In general, I meet that for resolve the topic of multithreading it's >> required to implement another thread over a work item. >> >> How does the asynchronic task can modified a variable of Knowledgebase? >> >> Can you give me an example? >> >> Pedro Buitrago >> >> >> >> _______________________________________________ >> rules-users mailing list* >> **rules-users(a)lists.jboss.org* <rules-users(a)lists.jboss.org&gt;* >> **https://lists.jboss.org/mailman/listinfo/rules-users*<https://lists.jboss.org/mailman/listinfo/rules-users> >> >> >> >> >> -- >> - *http://salaboy.wordpress.com* <http://salaboy.wordpress.com/> >> - *http://www.jbug.com.ar* <http://www.jbug.com.ar/> >> - Salatino "Salaboy" Mauricio - >> >> _______________________________________________ >> rules-users mailing list* >> **rules-users(a)lists.jboss.org* <rules-users(a)lists.jboss.org&gt;* >> **https://lists.jboss.org/mailman/listinfo/rules-users*<https://lists.jboss.org/mailman/listinfo/rules-users> >> >> >> >> _______________________________________________ >> rules-users mailing list* >> **rules-users(a)lists.jboss.org* <rules-users(a)lists.jboss.org&gt;* >> **https://lists.jboss.org/mailman/listinfo/rules-users*<https://lists.jboss.org/mailman/listinfo/rules-users> >> >> >> >> >> -- >> - *http://salaboy.wordpress.com* <http://salaboy.wordpress.com/> >> - *http://www.jbug.com.ar* <http://www.jbug.com.ar/> >> - Salatino "Salaboy" Mauricio - >> >> _______________________________________________ >> rules-users mailing list* >> **rules-users(a)lists.jboss.org* <rules-users(a)lists.jboss.org&gt;* >> **https://lists.jboss.org/mailman/listinfo/rules-users*<https://lists.jboss.org/mailman/listinfo/rules-users> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> >> > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users