[concurrency-interest] concurrency-oriented languages on the JVM

Doug Lea dl@cs.oswego.edu
Tue, 1 Jun 2004 08:01:00 -0400

> Erlang
> http://www.erlang.org/
> Mozart/Oz
> http://www.mozart-oz.org/
> ...
> haven't been ported to the JVM.  I've heard that
> this is because gaps in the JVM instruction set
> would make such ports dozens of times slower than
> their current native incarnations.
> So, my questions are:
> 1) Is this true with pre 1.5 JVMs?

I don't know. I was hoping someone who knows something about implementing
Erlang or Mozart would answer, but apparently not.

> 2) Does JSR-166 change this?

We would be surprised if there is any kind of
synchronization/threading support that people cannot build efficiently
from what's in JSR166. The only mismatch I know of offhand is that
Erlang uses a process-centric (no shared memory) rather than
thread-centric approach.  Very fine-grained implementations of
Isolates (JSR121) might be nicer for this but don't exist yet.  So
this would need to be enforced by compilers and runtime classes but I
wouldn't think it would add much if any overhead.