Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!udel!gatech!hubcap!billwolf%hazel.cs.clemson.edu
From: billwolf%hazel.cs.clemson.edu@hubcap.clemson.edu (William Thomas Wolfe, 2847 )
Newsgroups: comp.sw.components
Subject: Re: Real-time Garbage Collection
Message-ID: <6510@hubcap.clemson.edu>
Date: 19 Sep 89 18:49:23 GMT
References: <1929@hydra.gatech.EDU>
Sender: news@hubcap.clemson.edu
Reply-To: billwolf%hazel.cs.clemson.edu@hubcap.clemson.edu
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From article <1929@hydra.gatech.EDU>, by tynor@prism.gatech.EDU (Steve Tynor):
>>   expired without even consulting the database.  AWhere objects can have
>>   an infinite lifetime, a protocol can be devised whereby the database
>>   must be checked at least once per some arbitrary time period by all
>>   users, which will permit identification numbers to be recycled after
>>   one full time period of nonexistence.  Other protocols might be used
> 
> Gee. This sounds an awful lot like garbage collection to me.

   No... GC would involve verifying (at tremendous cost) that no more
   occurrences of a given identification number exist anywhere.  This
   protocol specifies that identification numbers EXPIRE AUTOMATICALLY 
   unless certain conditions are met.  GC is restricted to a particular
   machine; this protocol will function even in a distributed environment.
   
   Usually, the semantics of the object will allow even better controls,
   such as a fixed expiration date, but this protocol covers the worst case.


   Bill Wolfe, wtwolfe@hubcap.clemson.edu