diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index ee1f2b23a6d..a906cde2d11 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -396,16 +396,17 @@ always available.
 .. function:: getallocatedblocks()
 
    Return the number of memory blocks currently allocated by the interpreter,
-   regardless of their size.  This function is mainly useful for debugging
-   small memory leaks.  Because of the interpreter's internal caches, the
-   result can vary from call to call; you may have to call
-   :func:`_clear_type_cache()` to get more predictable results.
+   regardless of their size.  This function is mainly useful for tracking
+   and debugging memory leaks.  Because of the interpreter's internal
+   caches, the result can vary from call to call; you may have to call
+   :func:`_clear_type_cache()` and :func:`gc.collect()` to get more
+   predictable results.
+
+   If a Python build or implementation cannot reasonably compute this
+   information, :func:`getallocatedblocks()` is allowed to return 0 instead.
 
    .. versionadded:: 3.4
 
-   .. impl-detail::
-      Not all Python implementations may be able to return this information.
-
 
 .. function:: getcheckinterval()
 
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 055592ba070..41f1439741b 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -7,6 +7,7 @@
 import operator
 import codecs
 import gc
+import sysconfig
 
 # count the number of test runs, used to create unique
 # strings to intern in test_intern()
@@ -616,9 +617,13 @@ def test_debugmallocstats(self):
                          "sys.getallocatedblocks unavailable on this build")
     def test_getallocatedblocks(self):
         # Some sanity checks
+        with_pymalloc = sysconfig.get_config_var('WITH_PYMALLOC')
         a = sys.getallocatedblocks()
         self.assertIs(type(a), int)
-        self.assertGreater(a, 0)
+        if with_pymalloc:
+            self.assertGreater(a, 0)
+        else:
+            self.assertEqual(a, 0)
         try:
             # While we could imagine a Python session where the number of
             # multiple buffer objects would exceed the sharing of references,
diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c
index c82c978e4da..bbe2805bd16 100644
--- a/Objects/obmalloc.c
+++ b/Objects/obmalloc.c
@@ -1316,6 +1316,13 @@ PyObject_Free(void *p)
 {
     PyMem_FREE(p);
 }
+
+Py_ssize_t
+_Py_GetAllocatedBlocks(void)
+{
+    return 0;
+}
+
 #endif /* WITH_PYMALLOC */
 
 #ifdef PYMALLOC_DEBUG