Virtual Memory
http://csapp.cs.cmu.edu/2e/ch9-preview.pdf
https://howtodoinjava.com/java-7/nio/java-nio-2-0-memory-mapped-files-mappedbytebuffer-tutorial/
https://howtodoinjava.com/core-java/io/how-java-io-works-internally-at-lower-level/
https://blogs.msdn.microsoft.com/salvapatuel/2009/06/08/working-with-memory-mapped-files-in-net-4/
https://en.wikipedia.org/wiki/Virtual_memory