Re: [PATCH] Configure GMP to use GC allocation functions, remove bignum finalizers

[ludo@gnu.org (Ludovic Courtès)]

Hi!

Andy Wingo <wingo@pobox.com> skribis:

> I still this this is a good idea.  The key would be to GC more often
> when the heap image grows faster than GC'd memory is allocated.  We can
> detect this situation by computing (ImageSize_t+1 - ImageSize_t) /
> (LiveBytes_t+1 - LiveBytes_t), where ImageSize is some measure of the
> total process size, perhaps via getrusage(), and LiveBytes is
> GC_get_heap_size() - GC_get_free_bytes().

The problem is that this measurement doesn’t allow us to differentiate
between a growing heap with objects that may be freed as a result of
running the GC, and a growing heap just because the application needs
more malloc’d objects.

(I think this is the argument that was made against my __malloc_hook
patch back then. [0])

A longer term option may be to augment libgc with something akin to our
old scm_gc_register_collectable_memory.

WDYT?

Thanks,
Ludo’.

[0] http://thread.gmane.org/gmane.comp.programming.garbage-collection.boehmgc/4371