Hi there, I found a really interesting article discribing the inner workings of japaleno, a JVM written in JAVA, for JAVA. The programmers follow an approach that is appealing to me. They have written the main JVM in JAVA... http://www-4.ibm.com/software/developer/library/jalapeno/index.html To be short, they are dong the following: On startup, a classic VM (lets call it VM1) is loaded, which loads the main VM ( VM2 ). Both VM's are written in JAVA, but VM1 has been compiled to static machinecode, and is not really optimized. VM1 doesn't need to be oprimized, cause the only job it must do is to load and invoke VM2. VM2 has a very optimized JIT: it takes bytecodes and transformes them into machinecode. The last thing isn't really surprising, but it is if you consider that VM2 is written in JAVA it is. IBM claims that the entire source of the VM's contains only 1000 lines of C code. It's that small because the only thing they need to program in C are the glue-functions to IO, memory and interrrupts. All the other things suchs as thread-switching, memory-management and synchronisation are written in JAVA. There are also some other interesting issues addressed in this article, such as how they prevent normal users from executing privileged code, locking and parallel-garbage-collecting. I think that this approach should also be interesting to JOS: write the VM in JAVA insteadof C++... Just some thoughts. Fushion. _______________________________________________ Kernel maillist - [EMAIL PROTECTED] http://jos.org/mailman/listinfo/kernel
