Re: [Chicken-hackers] GC and heap growth percentage question

[Felix]

From: Peter Bex <address@hidden>
Subject: Re: [Chicken-hackers] GC and heap growth percentage question
Date: Sun, 24 Jun 2012 20:13:56 +0200

> On Sun, Jun 24, 2012 at 01:44:18PM +0200, Felix wrote:
>> > IIUC, this means that whenever more stuff is allocated between two GCs
>> > (old heap + stack?) than twice the heap, it will fail.  I'm not sure yet
>> > how this situation would happen, but there are a lot of places which hold
>> > values that are remarked, so I can imagine there could be situations
>> > where these taken together are more than twice the current heap.
>> 
>> This would mean either the nursery is bigger than one half of the new
>> space (very unlikely) or that data is copied more than once (which
>> would be a bug).
> 
> I noticed that when the panic happens, gc_mode = GC_REALLOC.  This is
> sort of a special situation.  Could it be the data is copied more than
> once in this case?

Hard to say. I just hope that this is nothing that needs hacking the
forwarding logic of the collector. Getting it to work was endless toil
and I will not do it again nor will I endorse changes without getting
seriously harassed.


cheers,
felix