diff --git a/Lib/test/test_iter.py b/Lib/test/test_iter.py
index 5878c79..e424303 100644
--- a/Lib/test/test_iter.py
+++ b/Lib/test/test_iter.py
@@ -1,7 +1,7 @@
 # Test iterators.
 
 import unittest
-from test.support import run_unittest, TESTFN, unlink, gc_collect
+from test.support import run_unittest, TESTFN, unlink, cpython_only
 
 # Test result of triple loop (too big to inline)
 TRIPLETS = [(0, 0, 0), (0, 0, 1), (0, 0, 2),
@@ -761,8 +761,9 @@
         (a, b), (c,) = IteratingSequenceClass(2), {42: 24}
         self.assertEqual((a, b, c), (0, 1, 42))
 
-        # Test reference count behavior
 
+    @cpython_only
+    def test_ref_counting_behavior(self):
         class C(object):
             count = 0
             def __new__(cls):
@@ -775,7 +776,6 @@
         x = C()
         self.assertEqual(C.count, 1)
         del x
-        gc_collect()
         self.assertEqual(C.count, 0)
         l = [C(), C(), C()]
         self.assertEqual(C.count, 3)
@@ -784,7 +784,6 @@
         except ValueError:
             pass
         del l
-        gc_collect()
         self.assertEqual(C.count, 0)