Geoff Pole [http://community.jboss.org/people/instanceof] created the discussion "Re: StatefulKnowledgeSession signalEvent method" To view the discussion, visit: http://community.jboss.org/message/627079#627079 -------------------------------------------------------------- Hi, In case this helps others. I had this slightly backwards. It wasn't the second signal event call that was making the ProcessInstancesWaitingForEvent run. Instead this query appears to run every time a process enters and 'End' node. Presumably it does this so that it can find any workflows that may be listening for an End event. I don't know the reason why the ProcessInstancesWaitingForEvent runs so slowly (Oracle 11g) when there are many workflow instances that are waiting for events, but I did find that by applying this index reduced the running time from around 45 seconds to under 1 second with 20000 workflow instances. CREATE unique INDEX  idx_eventtypes_id_elem    ON EventTypes (instanceid, element) I tested this up to 100000 workflow instances and the query still runs sub second. Cheers, Geoff -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/627079#627079] Start a new discussion in jBPM at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]