Re: [Gc] weak maps and libgc
ivmai at mail.ru
Wed Oct 26 01:18:44 PDT 2011
26 10 2011, 00:06 Andy Wingo <wingo at pobox.com>:
> On Fri 21 Oct 2011 16:40, Ivan Maidanski <ivmai at mail.ru> writes:
> > Could you please summarize your past writings about the
> > implementations difficulties? Thanks.
> More concretely, I would be happy if:
> (1) There were a variant of GC_register_disappearing_link that also
> incremented an `unsigned long' somewhere in memory. This would
> allow me to keep an accurate count of how many items are in a weak
> hash table, and remove my need to run something after GC.
You mean statistic counter, right?
> (2) There were a function to move disappearing links, perhaps callable
> only within the alloc lock.
> I did some profiling today with the open-addressed table. It has
> to shuffle items around sometimes. Unregistering then registering
> disappearing links shows up pretty high on the profile.
Is my understanding correct - you want to optimize the following:
// assume GC_general_register_disappearing_link(&link, obj1);
Right? If yes, I don't mind again.
> (3) It would be nice if there were a callback after GC. It would let
> me accurately measure the time in GC, for example. This isn't
> relevant to the current discussion though.
What's about existing GC_set_start_callback?
> What do you think? I am happy to look at coding up these features, but
> I would like your input first.
Ok. My 'input' is above.
More information about the Gc