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From: ddyer@netcom.com (Dave Dyer)
Subject: Re: Reference Counting (was Re: Searching Method for Incremental Garbage Collection)
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Date: Mon, 21 Nov 1994 19:34:58 GMT
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I believe the ultimate in reference counting GC was achieved by
Interlisp-D and it's successors.  There, a couple of simple techniques
reduced the storage and computational overhead for reference counting
to very nominal levels.  The two tricks I remember are that pointers
in the active stack are not reference counted, and that the default
reference count of "1" for a live object is implicit, so only objects
with more than one reference have to have an explicitly allocated
count cell.

