Implemented Martin's suggestion to clear the free lists during the garbage collection of the highest generation.

5 files changed, 73 insertions, 25 deletions

diff --git a/Objects/classobject.c b/Objects/classobject.c
index 759027b..6c77153 100644
--- a/Objects/classobject.c
+++ b/Objects/classobject.c
@@ -2626,9 +2626,11 @@ PyTypeObject PyMethod_Type = {
 
 /* Clear out the free list */
 
-void
-PyMethod_Fini(void)
+int
+PyMethod_ClearFreeList(void)
 {
+	int freelist_size = numfree;
+	
 	while (free_list) {
 		PyMethodObject *im = free_list;
 		free_list = (PyMethodObject *)(im->im_self);
@@ -2636,4 +2638,11 @@ PyMethod_Fini(void)
 		numfree--;
 	}
 	assert(numfree == 0);
+	return freelist_size;
+}
+
+void
+PyMethod_Fini(void)
+{
+	(void)PyMethod_ClearFreeList();
 }
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
index df9c2e0..025431e 100644
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -889,10 +889,11 @@ PyFrame_LocalsToFast(PyFrameObject *f, int clear)
 }
 
 /* Clear out the free list */
-
-void
-PyFrame_Fini(void)
+int
+PyFrame_ClearFreeList(void)
 {
+	int freelist_size = numfree;
+	
 	while (free_list != NULL) {
 		PyFrameObject *f = free_list;
 		free_list = free_list->f_back;
@@ -900,6 +901,13 @@ PyFrame_Fini(void)
 		--numfree;
 	}
 	assert(numfree == 0);
+	return freelist_size;
+}
+
+void
+PyFrame_Fini(void)
+{
+	(void)PyFrame_ClearFreeList();
 	Py_XDECREF(builtin_object);
 	builtin_object = NULL;
 }
diff --git a/Objects/methodobject.c b/Objects/methodobject.c
index 0d9cf1c..d661c47 100644
--- a/Objects/methodobject.c
+++ b/Objects/methodobject.c
@@ -353,9 +353,11 @@ Py_FindMethod(PyMethodDef *methods, PyObject *self, const char *name)
 
 /* Clear out the free list */
 
-void
-PyCFunction_Fini(void)
+int
+PyCFunction_ClearFreeList(void)
 {
+	int freelist_size = numfree;
+	
 	while (free_list) {
 		PyCFunctionObject *v = free_list;
 		free_list = (PyCFunctionObject *)(v->m_self);
@@ -363,6 +365,13 @@ PyCFunction_Fini(void)
 		numfree--;
 	}
 	assert(numfree == 0);
+	return freelist_size;
+}
+
+void
+PyCFunction_Fini(void)
+{
+	(void)PyCFunction_ClearFreeList();
 }
 
 /* PyCFunction_New() is now just a macro that calls PyCFunction_NewEx(),
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index dfd2a16..e9cb3ef 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -832,19 +832,18 @@ _PyTuple_Resize(PyObject **pv, Py_ssize_t newsize)
 	return 0;
 }
 
-void
-PyTuple_Fini(void)
+int
+PyTuple_ClearFreeList(void)
 {
+	int freelist_size = 0;
 #if PyTuple_MAXSAVESIZE > 0
 	int i;
-
-	Py_XDECREF(free_list[0]);
-	free_list[0] = NULL;
-
 	for (i = 1; i < PyTuple_MAXSAVESIZE; i++) {
 		PyTupleObject *p, *q;
 		p = free_list[i];
+		freelist_size += numfree[i];
 		free_list[i] = NULL;
+		numfree[i] = 0;
 		while (p) {
 			q = p;
 			p = (PyTupleObject *)(p->ob_item[0]);
@@ -852,6 +851,20 @@ PyTuple_Fini(void)
 		}
 	}
 #endif
+	return freelist_size;
+}
+	
+void
+PyTuple_Fini(void)
+{
+#if PyTuple_MAXSAVESIZE > 0
+	/* empty tuples are used all over the place and applications may
+	 * rely on the fact that an empty tuple is a singleton. */
+	Py_XDECREF(free_list[0]);
+	free_list[0] = NULL;
+
+	(void)PyTuple_ClearFreeList();
+#endif
 }
 
 /*********************** Tuple Iterator **************************/
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 74b4796..3e15f53 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -8853,10 +8853,29 @@ void _PyUnicode_Init(void)
 
 /* Finalize the Unicode implementation */
 
+int
+PyUnicode_ClearFreeList(void)
+{
+    int freelist_size = numfree;
+    PyUnicodeObject *u;
+
+    for (u = free_list; u != NULL;) {
+	PyUnicodeObject *v = u;
+	u = *(PyUnicodeObject **)u;
+	if (v->str)
+	    PyMem_DEL(v->str);
+	Py_XDECREF(v->defenc);
+	PyObject_Del(v);
+	numfree--;
+    }
+    free_list = NULL;
+    assert(numfree == 0);
+    return freelist_size;
+}
+
 void
 _PyUnicode_Fini(void)
 {
-    PyUnicodeObject *u;
     int i;
 
     Py_XDECREF(unicode_empty);
@@ -8868,17 +8887,7 @@ _PyUnicode_Fini(void)
 	    unicode_latin1[i] = NULL;
 	}
     }
-
-    for (u = free_list; u != NULL;) {
-	PyUnicodeObject *v = u;
-	u = *(PyUnicodeObject **)u;
-	if (v->str)
-	    PyMem_DEL(v->str);
-	Py_XDECREF(v->defenc);
-	PyObject_Del(v);
-    }
-    free_list = NULL;
-    numfree = 0;
+    (void)PyUnicode_ClearFreeList();
 }
 
 #ifdef __cplusplus