Re: Re: A non-sucking garbage collector

Mark Hahn wrote:
...

> Of course there is a overhead of memory (up to a factor of two) due to
> the fact that you need the old arena and the new at the same time.  This
> is reduced if you have multiple generation arenas and the old isn't
> copied.  So adding the generational enhancement improves both speed and
> memory requirements.

I agree this is a simple and efficient scheme to do garbage
collection, at the price that you have _all_ object references
one level of indirecton away, every pointer from object to
object must go through the global object table, and you
probably _never_ can rely on any direct reference, if a garbage
collection can happen in between.
I have no clue how big the cost is. Maybe it is even more
efficient than the Python combination of refcounting/generational gc.
If you can make sure that gc can happen only at certain times,
you can keep references in registers long enough.
What stays is the double indirection all over the place.
Do you think it is easy to undo this change if it turns out to
be inefficient?

ciao - chris
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