Meyer, OO and concurrency  Richard A. O'Keefe <> Tue Aug 2
01:00:19 CEST 2005  I wrote:         > > and there are still
issues about copying.  Alex Arnon <> wrote:         1) I
understood that the process dictionary is on-heap.
So, what copying issues are there?  Remember, I was talking
about the public interface and documentation. Nowhere in that
documentation is it promised that "the process dictionary is on-
heap".  The issues about copying concern the fact that we don't
*KNOW* whether/how much copying is done.  For example, an
entirely valid implementation of the process dictionary
*interface* would involve a second process holding the data,
with gets and puts done by sending messages to that other
process.  There is another issue as well:  the efficient
concurrent garbage collector for Erlang that was published
relied on data in the heap not changing.  But the process
dictionary does change.  So that has *some* effect on the
structure and/or efficiency of the garbage collector.  What/how
much?  We don't know.          2)