Robert Klemme wrote:
> Btw, but the issue with stopping the world would still not go away.
> Too bad.  A possible solution would be to implement the callback in a
> way that it places all references in a Java collection.  Only after it
> finishes the Ruby land callback is invoked for each instance. The
> downside is that you need more space (i.e. for the collection which
> could become largish) but on the plus side is that you do not have any
> overhead (other than incurred by JVMTI) during "normal" operation and
> you can limit the stop the world time to just the copying phase which
> might be acceptable.  Charles, what do you think?

It's certainly possible to do this, but it would probably need to create 
a giant strong-referenced list of objects for iteration. Part of my hard 
rules for implementing ObjectSpace is that it MUST NOT interfere with an 
object's normal lifecycle.

- Charlie