Ken, In Drools, timers etc. are linked to a session (where the session can contain process instances, timers, data, rule evaluations, etc.). So, even if you are using Drools Flow in a clustered environment, where you could have a number of independent sessions running simultaneously, the timer will always be associated to that session. There are two possible strategies then: either (1) you keep the session online for ever (your cluster has a number of running sessions and you're possibly using persistence to restore in case of system failure), and the timers will fire in that session only when the time is right or (2) you only keep your session alive when it is necessary so sessions can go offline, where you could then use a scheduler to make sure the session is brought back online (from persistent storage) whenever a timer should fire in an offline session. The latter is currently being implemented as a community contribution. Kris Ken Young wrote: > We are looking at embedding Drools 5.1 (specifically Drools Flow) in our application, but I am coming up short on determining how to configure clustering, or the support. > > Specifically, I want to ensure that background processes that are taking place (reminders, timers, etc.) only happen once on a cluster. Does drools support this and how? > > In other software that we have clustered (Quartz for example), where a shared database lock is used to ensure the the processing happens in one place. I was wondering if Drools 5.1 worked in a similar fashion. > > Thanks > Ken > > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users >

It related to this issue: https://jira.jboss.org/browse/JBRULES-2616 Diego, is there something publicly available already? Kris Ken Young wrote: > Thank you for the reply.  I a not sure where the community effort lives, but would it be possible send a link in order to take a look? > > > > Ken > On Oct 28, 2010, at 8:28 PM, Kris Verlaenen wrote: > > >> Ken, >> >> In Drools, timers etc. are linked to a session (where the session can >> contain process instances, timers, data, rule evaluations, etc.). So, >> even if you are using Drools Flow in a clustered environment, where you >> could have a number of independent sessions running simultaneously, the >> timer will always be associated to that session. There are two possible >> strategies then: either (1) you keep the session online for ever (your >> cluster has a number of running sessions and you're possibly using >> persistence to restore in case of system failure), and the timers will >> fire in that session only when the time is right or (2) you only keep >> your session alive when it is necessary so sessions can go offline, >> where you could then use a scheduler to make sure the session is brought >> back online (from persistent storage) whenever a timer should fire in an >> offline session. The latter is currently being implemented as a >> community contribution. >> >> Kris >> >> Ken Young wrote: >> >>> We are looking at embedding Drools 5.1 (specifically Drools Flow) in our application, but I am coming up short on determining how to configure clustering, or the support. >>> >>> Specifically, I want to ensure that background processes that are taking place (reminders, timers, etc.) only happen once on a cluster.  Does drools support this and how? >>> >>> In other software that we have clustered (Quartz for example), where a shared database lock is used to ensure the the processing happens in one place.  I was wondering if Drools 5.1 worked in a similar fashion. >>> >>> Thanks >>> Ken >>> >>> >>> _______________________________________________ >>> 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