[gclist] Name that hypothesis

Charles Fiterman cef@geode.geodesic.com
Tue, 03 Dec 1996 13:19:53 +0000


>Right. Clearly the Ordering Assumption (thanks to Dave Mason) is
>related to this "Rare Modification Hypothesis": old objects are rarely
>modified. The RMH is very important to some implementations of write
>barriers, and implies the OA. But the implication doesn't go the other
>way: there could be a few old objects, updated very frequently.
>
>(maybe the RMH should be "few old objects are ever modified").

I would like to add a new hypothesis and emphasise the hypothesis part. 

1. If an object is modified it is likely to be modified again and soon.
2. The Collector may not need to know about the modifications. Henry
   Baker has noted this in some of his papers.

If you use a pointer to traverse a linked list the collector doesn't
have to worry about that pointer in write barrier applications.


Charles Fiterman	Geodesic Systems
Phone 312-728-7196	4745 N. Ravenswood Suite 111
Fax   312-728-6096	Chicago Il 60015
cef@geodesic.com

A computer language without garbage collection
  is like a city without garbage collection.