Two Virtual Machines
Last updated at 10:20 pm UTC on 8 December 2006
Release of Squeak 2.0 had two complete copies of the Squeak VM (the application program that runs on your machine). The first, was simply an updated version of the standard bytecode interpreter that we have been using for the last year or so. The second, the "Jitter", translates Squeak bytecodes on demand to a more efficient representation for faster execution.
Release 2.2 has gone back to just one Virtual Machine.
Ian Piumarta at INRIA in France built the Jitter as an experiment. He is now working on a full translator to native code.
The experimental "Jitter", as Ian affectionately calls it, does run faster in many cases, but has some bugs. For now, use the main VM, and wait for Ian's next effort.
If you are interested in Jitter, it is entirely written in Squeak, and can be browsed in the 'Squeak-Jitter' category. If you are not interested, it can all be removed by the space-saving statments in the welcome window.
(revised by tk 16 Sep 98)