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Commit 807fd11

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christian.heimes
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Implemented Martin's suggestion to clear the free lists during the garbage collection of the highest generation.
git-svn-id: http://svn.python.org/projects/python/trunk@60797 6015fed2-1504-0410-9fe1-9d1591cc4771
1 parent dbb0623 commit 807fd11

15 files changed

Lines changed: 131 additions & 25 deletions

‎Doc/c-api/method.rst‎

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@@ -63,3 +63,10 @@ There are some useful functions that are useful for working with method objects.
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.. cfunction:: PyObject* PyMethod_GET_SELF(PyObject *meth)
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Macro version of :cfunc:`PyMethod_Self` which avoids error checking.
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.. cfunction:: int PyMethod_ClearFreeList(void)
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Clear the free list. Return the total number of freed items.
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.. versionadded:: 2.6

‎Doc/c-api/tuple.rst‎

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@@ -115,3 +115,10 @@ Tuple Objects
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.. versionchanged:: 2.2
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Removed unused third parameter, *last_is_sticky*.
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.. cfunction:: int PyMethod_ClearFreeList(void)
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Clear the free list. Return the total number of freed items.
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.. versionadded:: 2.6

‎Doc/c-api/unicode.rst‎

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@@ -89,6 +89,13 @@ access internal read-only data of Unicode objects:
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Return a pointer to the internal buffer of the object. *o* has to be a
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:ctype:`PyUnicodeObject` (not checked).
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.. cfunction:: int PyUnicode_ClearFreeList(void)
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Clear the free list. Return the total number of freed items.
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.. versionadded:: 2.6
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Unicode provides many different character properties. The most often needed ones
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are available through these macros which are mapped to C functions depending on
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the Python configuration.

‎Include/classobject.h‎

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@@ -74,6 +74,7 @@ PyAPI_FUNC(PyObject *) _PyInstance_Lookup(PyObject *pinst, PyObject *name);
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PyAPI_FUNC(int) PyClass_IsSubclass(PyObject *, PyObject *);
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PyAPI_FUNC(int) PyMethod_ClearFreeList(void);
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#ifdef __cplusplus
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}

‎Include/frameobject.h‎

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@@ -75,6 +75,8 @@ PyAPI_FUNC(PyObject **) PyFrame_ExtendStack(PyFrameObject *, int, int);
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PyAPI_FUNC(void) PyFrame_LocalsToFast(PyFrameObject *, int);
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PyAPI_FUNC(void) PyFrame_FastToLocals(PyFrameObject *);
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PyAPI_FUNC(int) PyFrame_ClearFreeList(void);
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#ifdef __cplusplus
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}
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#endif

‎Include/methodobject.h‎

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@@ -85,6 +85,8 @@ typedef struct {
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PyObject *m_module; /* The __module__ attribute, can be anything */
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} PyCFunctionObject;
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PyAPI_FUNC(int) PyCFunction_ClearFreeList(void);
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#ifdef __cplusplus
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}
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#endif

‎Include/tupleobject.h‎

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@@ -52,6 +52,8 @@ PyAPI_FUNC(PyObject *) PyTuple_Pack(Py_ssize_t, ...);
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/* Macro, *only* to be used to fill in brand new tuples */
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#define PyTuple_SET_ITEM(op, i, v) (((PyTupleObject *)(op))->ob_item[i] = v)
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PyAPI_FUNC(int) PyTuple_ClearFreeList(void);
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#ifdef __cplusplus
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}
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#endif

‎Include/unicodeobject.h‎

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@@ -209,6 +209,7 @@ typedef PY_UNICODE_TYPE Py_UNICODE;
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# define _PyUnicode_AsDefaultEncodedString _PyUnicodeUCS2_AsDefaultEncodedString
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# define _PyUnicode_Fini _PyUnicodeUCS2_Fini
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# define _PyUnicode_Init _PyUnicodeUCS2_Init
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# define PyUnicode_ClearFreeList PyUnicodeUCS2_ClearFreelist
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# define _PyUnicode_IsAlpha _PyUnicodeUCS2_IsAlpha
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# define _PyUnicode_IsDecimalDigit _PyUnicodeUCS2_IsDecimalDigit
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# define _PyUnicode_IsDigit _PyUnicodeUCS2_IsDigit
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# define _PyUnicode_AsDefaultEncodedString _PyUnicodeUCS4_AsDefaultEncodedString
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# define _PyUnicode_Fini _PyUnicodeUCS4_Fini
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# define _PyUnicode_Init _PyUnicodeUCS4_Init
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# define PyUnicode_ClearFreeList PyUnicodeUCS2_ClearFreelist
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# define _PyUnicode_IsAlpha _PyUnicodeUCS4_IsAlpha
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# define _PyUnicode_IsDecimalDigit _PyUnicodeUCS4_IsDecimalDigit
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# define _PyUnicode_IsDigit _PyUnicodeUCS4_IsDigit
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extern "C" {
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#endif
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PyAPI_FUNC(int) PyUnicode_ClearFreeList(void);
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/* --- Unicode Type ------------------------------------------------------- */
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typedef struct {

‎Misc/NEWS‎

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@@ -12,6 +12,10 @@ What's New in Python 2.6 alpha 1?
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Core and builtins
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-----------------
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- Clear all free list during a gc.collect() of the highest generation in order
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to allow pymalloc to free more arenas. Python may give back memory to the
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OS earlier.
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- Issue #2045: Fix an infinite recursion triggered when printing a subclass of
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collections.defaultdict, if its default_factory is set to a bound method.
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‎Modules/gcmodule.c‎

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@@ -19,6 +19,7 @@
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*/
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#include "Python.h"
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#include "frameobject.h" /* for PyFrame_ClearFreeList */
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/* Get an object's GC head */
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#define AS_GC(o) ((PyGC_Head *)(o)-1)
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}
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}
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/* Clear all free lists
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* All free lists are cleared during the collection of the highest generation.
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* Allocated items in the free list may keep a pymalloc arena occupied.
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* Clearing the free lists may give back memory to the OS earlier.
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*/
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static void
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clear_freelists(void)
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{
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(void)PyMethod_ClearFreeList();
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(void)PyFrame_ClearFreeList();
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(void)PyCFunction_ClearFreeList();
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(void)PyTuple_ClearFreeList();
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(void)PyUnicode_ClearFreeList();
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}
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/* This is the main function. Read this to understand how the
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* collection process works. */
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static Py_ssize_t
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*/
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(void)handle_finalizers(&finalizers, old);
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/* Clear free list only during the collection of the higest
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* generation */
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if (generation == NUM_GENERATIONS-1) {
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clear_freelists();
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}
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if (PyErr_Occurred()) {
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if (gc_str == NULL)
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gc_str = PyString_FromString("garbage collection");

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