Architectural Patterns

Leader election pattern

The problem description—a typical cloud application has many tasks working in a coordinated manner. These tasks could all be instances running the same code and requiring access to the same resources, or they might be working together in parallel to perform the individual parts of a complex calculation. The task instances might run separately for much of the time, but it might also be necessary to coordinate the actions of each instance to ensure that they don't conflict, cause contention for shared resources, or accidentally interfere with the work that other task instances are performing.

For example, cloud systems guarantee scalability through scale-up or scale-out. In the case of scale-out (horizontal scaling), ...