[virtmach] garbage collection

Manoj Plakal plakal@cs.wisc.edu
Thu, 18 May 2000 11:59:35 -0500

thaddaeus.frogley@creaturelabs.com wrote (Thu, May 18, 2000 at 04:54:47PM +0100) :
> Anyone got any links and / or advice on garbage collection ? :)

	Apart from the Jones & Lins book ("Garbage Collection"),
	there's Paul Wilson's survey article:

> I'm thinking, VM (obviously), single threaded environment, indexes into a
> repository containing polymorphic objects act as handles and are stored on
> an untyped stack.  

	If you want a simple and incremental technique, you
	could try reference counting. The VM used in Lucent's
	Inferno (it's called Dis) uses reference counting
	because it can collect garbage quickly (especially
	large expensive objects such as bitmaps) and it's an 
	incremental technique making it good for real-time and 
	embedded environments. 

	The ref counter cannot collect cyclic garbage so you
	will probably need to use a tracing collector as 
	a backup occasionally (or don't bother if you know you
	are not going to have too many cycles). And you have	
	to worry about not putting too much overhead on
	common application operations which have to be
	instrumented to maintain ref counts. See the
	literature for proposed workarounds.