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From: neves@AI.WISC.EDU (David M. Neves)
Newsgroups: mod.ai
Subject: Re: Xerox vs Symbolics -- Reference counts vs Garbage collection
Message-ID: <8609262352.AA10266@ai.wisc.edu>
Date: Fri, 26-Sep-86 19:52:26 EDT
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Posted: Fri Sep 26 19:52:26 1986
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Reply-To: neves@ai.wisc.edu (David M. Neves)
Organization: U of Wisconsin CS Dept
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When I was using MIT Lisp Machines (soon to become Symbolics) years
ago nobody used the garbage collector because it slowed down the
machine and was somewhat buggy.  Instead people operated for hours/days
until they ran out of space and then rebooted the machine.  The only
time I turned on the garbage collector was to compute 10000 factorial.
Do current Symbolics users use the garbage collector?

   "However, it is apparent that reference counters will never
   reclaim circular list structure."  

This is a common complaint about reference counters.  However I don't
believe there is very many circular data structures in real Lisp code.
Has anyone looked into this?  Has any Xerox user run out of space
because of circular data structures in their environment?

-- 
David Neves, Computer Sciences Department, University of Wisconsin-Madison
Usenet:  {allegra,heurikon,ihnp4,seismo}!uwvax!neves
Arpanet: neves@rsch.wisc.edu