We have seen that segregating the application by criticality is something very positive. However, a common misconception is the reuse of components. A classic example of bad resource sharing is the reuse of a database. No matter how optimized your load balancer is, the threading level of criticality to your own application, or how well they have divided their domains, if all or most of your application depends on a single physical component, the collapse is imminent.
The following diagram is a great example of a sloppy design. All components of the application, regardless of the domain, depend on the same physical component, in this case, the database. This type of mistake is also common when it comes to the cache ...
