Metacircular virtual machines: Jikes BA ch 10

This paper presents another example of a system that emphasizes the advantages of using a single language for runtime and implementation of the system. Jikes is a VM developed completely in java to run java applications. The author describes the component of the system after first presenting the concept of self-hosting, which is writing a programming language in its own language.

The author argues that using java to write the components had many advantages. I completely agree that using Java’s collection simplifies the development by allowing the components to focus on their roles. It is a great advantage of Java compared to languages likes C where the programmer needs to take care of managing the underlying data structure and memory.

Jikes has its own threading model because there was a lack of threading support in operating system when it was developed. To the question of knowing if it was a good choice? I think they did not have any choice. There was no support for threading so they had to develop one. This has advantage because it allowed them to adapt the threading model to the need of the system allowing them to run many threads. The only downside as mentioned in the chapter is that it can have some undesirable performance problems because the OS does not know about the JVM managing threads.