The new release tweaks performance by talking advantage of Ahead-of-Time (AOT) or Just-in-Time (JIT) compilers for the JVM.
JRuby is the implementation of Ruby that runs atop the Java Virtual Machine (JVM). Instead of using the C libraries of standard Ruby, it uses Java libraries. Sun has open sourced it, and according to Charles Nutter, Sun’s core JRuby developer, about half the features of the new version came from outside Sun.
The new release also improves compatibility with standard Ruby by bridging some of the features of standard Ruby that are not available on the JVM. JRuby also faces a similar challenge mapping to Java, in that its libraries only address a subset of what’s available on the JVM. Sun says that the next version of JRuby will address that.
Sun expects JRuby 1.1 to be available in final firm by year end.
