GC performance - was Re: [gclist] GC topics

[Tyson Richard DOWD]

> 
> >
> >Writing our own precise GC has so far consumed the work of one honours
> >thesis and two summer studentships (i.e. about 6 man-months of work),
> >and it still isn't complete.
> 
>    I am sorry to ask you this question.
> 
>    What is the dieeerence between precise GC and conservative GC.
> 
>    Do you mean compile-time-gc is included within precise GC?
> 
>   and standard mark-scan-sweep, copying collectors are conservative?
> 

Essentially, conservative GC scans memory for any stored values that
look like pointers and assume that they are pointers. Typically 
any pointers to allocated memory are assumed to be live, and any allocated
memory without pointers to it are dead, and can be re-used. 

Precise GC has accurate information about the location of pointers, and
their live/deadness, so tends to be able to find more garbage, possibly
more quickly. Usually this information is supplied by the user or compiler.

-- 
       Tyson Dowd           #          Another great idea from the 
			    #		 people who brought you
  trd@mundil.cs.mu.oz.au    #               Beer Milkshakes!
http://www.cs.mu.oz.au/~trd #	         Confidence --- Red Dwarf