--- Allen Wirfs-Brock
<Allen_Wirfs-Brock at Instantiations.com> wrote:
> 
> The best explanation I've ever heard for why you are
> unlikely to see 
> garbage collection generalized in this manner was by
> George Bosworth of 
> Smalltalk/V fame.  George's explanation basically
> goes like this:  Garbage 
> collection is a resource management solution for a
> resource that fits a 
> particular  "economic" model (very large resource
> pool, each resource has a 
> very low value (who cares if you loose a few bytes
> out of megabytes), very 
> high churn rate, moderate wastage is acceptable,
> etc.).  Garbage collection 
> algorithms and policies are all designed and
> specifically optimized for 
> this specific resource management problem and simply
> are not appropriate 
> for the management of resources subject to a very
> difference set of 
> economics. In addition, there is no reason to
> believe that there is a 
> single universal resource management mechanism that
> can be used to 
> optimally manage all types of resources.
> 
> The problem with finalization is that it applies
> memory resource management 
> policies to other resources (like postgres
> connections) that have a very 
> different set of economics associated with them.
> 
> Allen_Wirfs-Brock at Instantiations.com
> 
> 

Well, that kind of argument encourages me to make my
"other resources" really large in terms of memory
consumption so that they cost roughly an appropriate
amount when expressed in memory economics.  I think a
Postgres connection should be...umm...18Mbytes.  

It seems to me that it would be a workable comprimise
to use finalization for those objects which get/got
handed around and are hard to track, but then
something like an ensure: block to clean up the ones
where that is easy to do.  It seems to me that it
would give you good performance in the common case,
but then CYA (without requiring reference counting) in
the complicated one.  Does this just not work out well
in practice?

-andrew

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