Timer Event/Signal Event In Cluster Environment

As we transition to the new Hyland Community, some post links may be temporarily disrupted as we finalize redirects. We apologize for the inconvenience and are working to resolve this as quickly as possible. Details.

lijinting01

Environment Description: activiti 5.21.0 with spring boot 1.4.0.

Activiti is working in cluster environment, which each node has it's own activiti engine, sharing the same database schema.

My questions are:

If there is a timer event in the process definition, what happens when the timer event reached it's scheduled time? Will each node start a scheduled job execution respectively?

If there is a signal event in the process definition, what happens when a signal is thrown in one of those nodes? Will the signal broadcast to each node sharing the same database? 

trademak

Hi,

The Activiti job executor will poll the jobs table for executable jobs, so if you have more Engines (with the job executor enabled), more job executors will poll the jobs table. There's a locking mechanism implemented on the database level, so only one job executor can execute a job. So it's designed to work in a clustered environment.

A signal event will be handled by the Engine where the signal event is thrown. So only one Engine will handle the signal event.

Best regards,