diff --git a/README.markdown b/README.markdown
index 71c114a97..3d9e170c6 100644
--- a/README.markdown
+++ b/README.markdown
@@ -191,3 +191,11 @@ following steps:
   * Run the WebGL demo in examples/webgl_demo and make sure it looks
     ok.
 
+
+TODO
+====
+
+  * The HEAP memory space may not be implemented as a flat object in
+    all JS engines, especially when we use a lot of memory. Need to
+    investigate this.
+
diff --git a/test.py b/test.py
index 8f85e245b..d67fc17df 100644
--- a/test.py
+++ b/test.py
@@ -9,8 +9,12 @@
 
 exec(open(os.path.expanduser('~/.emscripten'), 'r').read())
 
+print
+print '==================================='
+print
+
 def run(filename):
-  return Popen(SPIDERMONKEY_ENGINE + ['-e', 'load("' + build + '");load("' + os.path.join('tests', 'testutils.js') + '")', filename], stdout=PIPE).communicate()[0]
+  return Popen(SPIDERMONKEY_ENGINE + ['-e', 'gcparam("maxBytes", 1024*1024*1024); load("' + build + '"); load("' + os.path.join('tests', 'testutils.js') + '")', filename], stdout=PIPE).communicate()[0]
 
 __counter = 0
 def stage(text):
@@ -57,8 +61,11 @@ def stage(text):
 5 : 11.75,-5.00,11.25
 6 : 2.35,-5.61,0.12
 total time:''' in output, output
-print '   stress benchmark: ' + output.split('\n')[-2]
+assert 'ok.' in output, output
+print '   stress benchmark: ' + output.split('\n')[-3]
 
+print
+print '==================================='
 print
 print 'ok.'
 
diff --git a/tests/stress.js b/tests/stress.js
index 4efb31925..f53d2e153 100644
--- a/tests/stress.js
+++ b/tests/stress.js
@@ -1,7 +1,17 @@
 // Stress test
 
-function main() {
+var readMemoryCeiling;
+try {
+  STATICTOP;
+  readMemoryCeiling = function() { return STATICTOP + _sbrk.DATASIZE }
+} catch(e) {
+  var mapping = getClosureMapping();
+  var key = '0';
+  for (k in eval(mapping['_sbrk'])) { key = k }; // hackish - relies on the order. TODO: fix
+  readMemoryCeiling = eval('(function() { return ' + mapping['STATICTOP'] + ' + ' + mapping['_sbrk'] + '.' + key + ' })');
+}
 
+function benchmark() {
   var collisionConfiguration = new Ammo.btDefaultCollisionConfiguration();
   var dispatcher = new Ammo.btCollisionDispatcher(collisionConfiguration);
   var overlappingPairCache = new Ammo.btDbvtBroadphase();
@@ -51,22 +61,15 @@ function main() {
     bodies.push(body);
   });
 
-  // Make sure we do not allocate memory!
-  var readMemoryCeiling;
-  try {
-    STATICTOP;
-    readMemoryCeiling = function() { return STATICTOP }
-  } catch(e) {
-    var mapping = getClosureMapping();
-    readMemoryCeiling = eval('(function() { return ' + mapping['STATICTOP'] + ' })');
-  }
-  var memoryStart = readMemoryCeiling();
+  var memoryStart;
 
   var trans = new Ammo.btTransform(); // taking this out of the loop below us reduces the leaking
 
   var startTime = Date.now();
 
   for (var i = 0; i < 450; i++) {
+    if (i === 250) memoryStart = readMemoryCeiling();
+
     dynamicsWorld.stepSimulation(1/60, 10);
     
     bodies.forEach(function(body, i) {
@@ -84,5 +87,24 @@ function main() {
   print('total time: ' + ((endTime-startTime)/1000).toFixed(3));
 }
 
-main();
+function testDestroy() {
+  var NUM = 1000; // enough to force an increase in the memory ceiling
+  var vec = new Ammo.btVector3(4, 5, 6);
+  var memoryStart = readMemoryCeiling();
+  for (var i = 0; i < NUM; i++) {
+    destroy(vec);
+    vec = new Ammo.btVector3(4, 5, 6);
+  }
+  destroy(vec);
+  assertEq(readMemoryCeiling(), memoryStart, 'Memory ceiling must remain stable!');
+  for (var i = 0; i < NUM; i++) {
+    vec = new Ammo.btVector3(4, 5, 6);
+  }
+  assertNeq(readMemoryCeiling(), memoryStart, 'Memory ceiling must increase without destroy()!');
+}
+
+benchmark();
+testDestroy();
+
+print('ok.')
 
diff --git a/tests/testutils.js b/tests/testutils.js
index eabd0ebbe..1e922681c 100644
--- a/tests/testutils.js
+++ b/tests/testutils.js
@@ -8,6 +8,14 @@ function assertEq(x, y, msg) {
   assert(x === y, (msg ? msg + ' : ' : '') + x + ' should be equal to ' + y + '.');
 }
 
+function assertNeq(x, y, msg) {
+  assert(x !== y, (msg ? msg + ' : ' : '') + x + ' should not be equal to ' + y + '.');
+}
+
+function assertLeq(x, y, msg) {
+  assert(x < y, (msg ? msg + ' : ' : '') + x + ' should be less than to ' + y + '.');
+}
+
 function getClosureMapping() {
   var raw = read('../builds/ammo.vars');
   var ret = {};