As Java developers, we’re no strangers to the concept of garbage collection. Our apps generate garbage all the time, and that garbage is meticulously cleaned out by CMS, G1, Azul C4, and other types of collectors. Basically, our apps are born to bring value to this world, but, nothing is perfect—including our apps that leave litter in the Java heap.

However, the story doesn’t end with the Java heap. In fact, it only starts there. Let’s take the example of a basic Java application that uses a relational database such as PostgreSQL and solid-state drives (SSDs) as a storage device. From here, we’ll explore how our applications generate garbage beyond the boundaries of the Java runtime.