Multithreading and Reactive Programming

In the previous chapter, we have described the Ahead-of-Time compiler of JDK 9 as one of the tools that can help to improve the performance of a Java application. In this chapter, we will look at another approach to support a high performance of an application by programmatically splitting the task between several workers. That was how the pyramids were built 4,500 years ago, and this method has not failed to deliver since then. But there is a limitation on how many laborers can be brought to work on the same project. The shared resources provide a ceiling to how much the workforce can be increased, whether the resources are counted in square feet and gallons (as the living quarters and water in the time of the pyramids) or in gigabytes and gigahertz (as the memory and processing power of a computer).

Allocation, usage, and limitations of...