Re: [Caml-list] Finding "lost" references to OCaml heap values

["Richard W.M. Jones" <rich@annexia.org>]

On Tue, Oct 06, 2015 at 01:57:52PM -0000, Maxime Ransan (BLOOMBERG/ 731 LEX) wrote:
> Just a hint about why the destructor is not called is that when using caml_alloc_custom at  https://github.com/libguestfs/libguestfs/blob/master/v2v/xml-c.c#L139, you are setting the used parameter to 0.  
> 
> As mentioned in http://caml.inria.fr/pub/docs/manual-ocaml-4.00/manual033.html#toc150 you can increase the ratio. A quick check would be to use a (used = 1, max = 1).

I guess this probably doesn't have anything to do with this
specific problem, since I'm calling the GC explicitly.

However you're certainly correct that we don't pay any attention to
passing decent values for caml_alloc_custom used/max.

One reason is that almost all OCaml programs we have are relatively
short running, so the pace of GC isn't much of an issue.  In fact, we
didn't notice that Gc.compact () was having "no effect" - it was only
noticed by an outside contributor who was doing a particularly long
v2v conversion and investigated further.

Thanks,

Rich.

-- 
Richard Jones
Red Hat