When: 30th October, 7pm @ The Outhouse pub

Title: Thinking outside the box: Optimizing non-Java JVM languages

Many languages target the Java virtual machine, from Ada to Xtend [1].

In this presentation, I will focus on functional languages like Scala

and Clojure. I am particularly concerned with the use of boxed value

types, which seems more prevalent on non-Java JVM languages. Custom

micro-benchmarks exhibit significant inefficiencies due to heavy use

of boxed integer types. I will describe the implementation of tagged

pointer optimisations in the OpenJDK interpreter [3] and demonstrate

how this improves performance for boxed integer allocation and method

invocation. However, with the exception of the Programming Language

Shootout benchmarks [4] I show there are currently few open source

Scala and Clojure applications that use boxed integers extensively.

This may change in future (discuss!)

[1] http://en.wikipedia.org/wiki/List_of_JVM_languages  ** market

opening - port a programming language beginning with 'Z' to the JVM,

see [2]

[2] http://en.wikipedia.org/wiki/List_of_programming_languages#Z

[3] http://openjdk.java.net

[4] http://benchmarksgame.alioth.debian.org