a note on garbage collection

a note on garbage collection

[Nelson H. F. Beebe]

This list has recently carried discussion of garbage collection, and
version 1.9.3 includes the Boehm-Demers-Weiser garbage collector.

There is newly-published paper that suggests there may be a better
alternative:

	Precise Garbage Collection for C
	Jon Rafkind, Adam Wick, John Regehr & Matthew Flatt
	http://www.cs.utah.edu/~regehr/papers/ismm15-rafkind.pdf

This is an outgrowth of Adam Wick's 2006 Ph.D. thesis from the
University of Utah, "Magpie: Precise Garbage Collection for C".

[Disclaimer: although we are at the same institution, I do not 
personally know any of the authors.]

-------------------------------------------------------------------------------
- Nelson H. F. Beebe                    Tel: +1 801 581 5254                  -
- University of Utah                    FAX: +1 801 581 4148                  -
- Department of Mathematics, 110 LCB    Internet e-mail: beebe@math.utah.edu  -
- 155 S 1400 E RM 233                       beebe@acm.org  beebe@computer.org -
- Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe/ -
-------------------------------------------------------------------------------

Re: a note on garbage collection

[Neil Jerram]

"Nelson H. F. Beebe" <beebe@math.utah.edu> writes:

> This list has recently carried discussion of garbage collection, and
> version 1.9.3 includes the Boehm-Demers-Weiser garbage collector.
>
> There is newly-published paper that suggests there may be a better
> alternative:
>
> 	Precise Garbage Collection for C
> 	Jon Rafkind, Adam Wick, John Regehr & Matthew Flatt
> 	http://www.cs.utah.edu/~regehr/papers/ismm15-rafkind.pdf
>
> This is an outgrowth of Adam Wick's 2006 Ph.D. thesis from the
> University of Utah, "Magpie: Precise Garbage Collection for C".

Hi Nelson,

Thanks for flagging this.  I wonder if it is related to the PLT GC
change that we discussed a couple of weeks ago here:

http://lists.gnu.org/archive/html/guile-devel/2009-08/msg00138.html

Regards,
        Neil

Re: a note on garbage collection

[Ludovic Courtès]

Hello,

"Nelson H. F. Beebe" <beebe@math.utah.edu> writes:

> There is newly-published paper that suggests there may be a better
> alternative:
>
> 	Precise Garbage Collection for C
> 	Jon Rafkind, Adam Wick, John Regehr & Matthew Flatt
> 	http://www.cs.utah.edu/~regehr/papers/ismm15-rafkind.pdf

Thanks for the pointer!  It looks like an interesting piece of work.

  Magpie is a source-to-source transformation for C programs that
  enables precise garbage collection, where precise means that integers
  are not confused with pointers, and the liveness of a pointer is
  apparent at the source level.

This is a relatively intrusive approach, as opposed to how Guile can be
embedded in C apps currently.

Besides, I’m always slightly dubious regarding the misidentified pointer
rhetoric, though.

     In our experience, however, conservative GC works poorly for
  long-running programs, such as a web server, a programming
  environment, or an operating system kernel. For such programs,
  conservative GC can trigger unbounded memory use due to linked lists
  [Boehm 2002] that manage threads and continuations;

Apparently, there’s also less fatalistic experience with such
applications, e.g., Hop (http://hop.inria.fr/).

Also, [Boehm 2002] suggests ways to avoid the infamous unbounded
retention in the queue (linked-list based) example and others.

I guess the real test for us will be Guile-in-Emacs...

Thanks,
Ludo’.