[polyml] Heap does not grow up to --maxheap

Dear all,

I have a PolyML program (below), for which maxheap is ignored: The heap is kept at the minheap size and does not grow automatically.

For the three runs below the maxheap is set to the same amount (4GB):

If I run: polyml --maxheap 4G --gcthreads 1 --minheap 4G < polybug.ml Terminates in less than 1 sec.

If I run: polyml --maxheap 4G --gcthreads 1 --minheap 500M < polybug.ml It does not terminate (at least not in 15 minutes)

If I run: polyml --maxheap 4G --gcthreads 1 --minheap 50M < polybug.ml I get 'Run out of store' exception.

Does the heap not grow automatically up to maxheap? Is there a way to make PolyML automatically adjust the heap size?

Tested both with 64bit polyml-5.5.0 (from Isabelle2013). And with current repository version (r1702).

Regards,

Cezary

-- datatype tree = Node of tree * tree | Leaf of int;

fun go acc (Leaf _) = acc + 1 | go acc (Node (l, r)) = go (go (acc + 1) l) r; fun size t = go 0 t;

fun build i j = if i <= 0 then Leaf j else Node (build (i-1) (2*j), build (i-2) (2*j+1));

val tim = ref (Timer.startRealTimer ()); fun tim_start () = tim := Timer.startRealTimer (); fun tim_print () = print (Time.toString (Timer.checkRealTimer (!tim)) ^ "\n");

val t = build 0 0; val al = 10000000; val a = Array.array (al, t);

tim_start (); fun irep i = if i = al then tim_print () else let val _ = Array.update (a,i,build 0 i) in irep (i + 1) end; irep 0; irep 0; irep 0; irep 0; irep 0;