Implement PEP 412: Key-sharing dictionaries (closes #13903)
Patch from Mark Shannon.
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@ -13,78 +13,20 @@ extern "C" {
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tuning dictionaries, and several ideas for possible optimizations.
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*/
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/*
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There are three kinds of slots in the table:
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1. Unused. me_key == me_value == NULL
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Does not hold an active (key, value) pair now and never did. Unused can
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transition to Active upon key insertion. This is the only case in which
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me_key is NULL, and is each slot's initial state.
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2. Active. me_key != NULL and me_key != dummy and me_value != NULL
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Holds an active (key, value) pair. Active can transition to Dummy upon
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key deletion. This is the only case in which me_value != NULL.
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3. Dummy. me_key == dummy and me_value == NULL
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Previously held an active (key, value) pair, but that was deleted and an
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active pair has not yet overwritten the slot. Dummy can transition to
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Active upon key insertion. Dummy slots cannot be made Unused again
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(cannot have me_key set to NULL), else the probe sequence in case of
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collision would have no way to know they were once active.
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Note: .popitem() abuses the me_hash field of an Unused or Dummy slot to
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hold a search finger. The me_hash field of Unused or Dummy slots has no
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meaning otherwise.
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*/
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/* PyDict_MINSIZE is the minimum size of a dictionary. This many slots are
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* allocated directly in the dict object (in the ma_smalltable member).
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* It must be a power of 2, and at least 4. 8 allows dicts with no more
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* than 5 active entries to live in ma_smalltable (and so avoid an
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* additional malloc); instrumentation suggested this suffices for the
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* majority of dicts (consisting mostly of usually-small instance dicts and
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* usually-small dicts created to pass keyword arguments).
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*/
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#ifndef Py_LIMITED_API
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#define PyDict_MINSIZE 8
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typedef struct _dictkeysobject PyDictKeysObject;
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/* The ma_values pointer is NULL for a combined table
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* or points to an array of PyObject* for a split table
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*/
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typedef struct {
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/* Cached hash code of me_key. */
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Py_hash_t me_hash;
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PyObject *me_key;
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PyObject *me_value;
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} PyDictEntry;
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/*
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To ensure the lookup algorithm terminates, there must be at least one Unused
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slot (NULL key) in the table.
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The value ma_fill is the number of non-NULL keys (sum of Active and Dummy);
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ma_used is the number of non-NULL, non-dummy keys (== the number of non-NULL
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values == the number of Active items).
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To avoid slowing down lookups on a near-full table, we resize the table when
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it's two-thirds full.
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*/
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typedef struct _dictobject PyDictObject;
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struct _dictobject {
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PyObject_HEAD
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Py_ssize_t ma_fill; /* # Active + # Dummy */
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Py_ssize_t ma_used; /* # Active */
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Py_ssize_t ma_used;
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PyDictKeysObject *ma_keys;
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PyObject **ma_values;
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} PyDictObject;
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/* The table contains ma_mask + 1 slots, and that's a power of 2.
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* We store the mask instead of the size because the mask is more
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* frequently needed.
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*/
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Py_ssize_t ma_mask;
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/* ma_table points to ma_smalltable for small tables, else to
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* additional malloc'ed memory. ma_table is never NULL! This rule
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* saves repeated runtime null-tests in the workhorse getitem and
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* setitem calls.
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*/
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PyDictEntry *ma_table;
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PyDictEntry *(*ma_lookup)(PyDictObject *mp, PyObject *key, Py_hash_t hash);
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PyDictEntry ma_smalltable[PyDict_MINSIZE];
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};
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#endif /* Py_LIMITED_API */
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PyAPI_DATA(PyTypeObject) PyDict_Type;
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@ -117,6 +59,8 @@ PyAPI_FUNC(void) PyDict_Clear(PyObject *mp);
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PyAPI_FUNC(int) PyDict_Next(
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PyObject *mp, Py_ssize_t *pos, PyObject **key, PyObject **value);
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#ifndef Py_LIMITED_API
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PyDictKeysObject *_PyDict_NewKeysForClass(void);
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PyAPI_FUNC(PyObject *) PyObject_GenericGetDict(PyObject *, void *);
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PyAPI_FUNC(int) _PyDict_Next(
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PyObject *mp, Py_ssize_t *pos, PyObject **key, PyObject **value, Py_hash_t *hash);
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#endif
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@ -131,6 +75,7 @@ PyAPI_FUNC(int) _PyDict_Contains(PyObject *mp, PyObject *key, Py_hash_t hash);
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PyAPI_FUNC(PyObject *) _PyDict_NewPresized(Py_ssize_t minused);
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PyAPI_FUNC(void) _PyDict_MaybeUntrack(PyObject *mp);
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PyAPI_FUNC(int) _PyDict_HasOnlyStringKeys(PyObject *mp);
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#define _PyDict_HasSplitTable(d) ((d)->ma_values != NULL)
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PyAPI_FUNC(int) PyDict_ClearFreeList(void);
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#endif
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@ -162,6 +107,11 @@ PyAPI_FUNC(int) PyDict_SetItemString(PyObject *dp, const char *key, PyObject *it
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PyAPI_FUNC(int) _PyDict_SetItemId(PyObject *dp, struct _Py_Identifier *key, PyObject *item);
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PyAPI_FUNC(int) PyDict_DelItemString(PyObject *dp, const char *key);
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#ifndef Py_LIMITED_API
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int _PyObjectDict_SetItem(PyTypeObject *tp, PyObject **dictptr, PyObject *name, PyObject *value);
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PyObject *_PyDict_LoadGlobal(PyDictObject *, PyDictObject *, PyObject *);
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#endif
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#ifdef __cplusplus
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}
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#endif
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@ -449,6 +449,7 @@ typedef struct _heaptypeobject {
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see add_operators() in typeobject.c . */
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PyBufferProcs as_buffer;
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PyObject *ht_name, *ht_slots, *ht_qualname;
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struct _dictkeysobject *ht_cached_keys;
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/* here are optional user slots, followed by the members. */
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} PyHeapTypeObject;
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@ -517,7 +518,6 @@ PyAPI_FUNC(PyObject *) _PyObject_NextNotImplemented(PyObject *);
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PyAPI_FUNC(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *);
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PyAPI_FUNC(int) PyObject_GenericSetAttr(PyObject *,
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PyObject *, PyObject *);
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PyAPI_FUNC(PyObject *) PyObject_GenericGetDict(PyObject *, void *);
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PyAPI_FUNC(int) PyObject_GenericSetDict(PyObject *, PyObject *, void *);
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PyAPI_FUNC(Py_hash_t) PyObject_Hash(PyObject *);
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PyAPI_FUNC(Py_hash_t) PyObject_HashNotImplemented(PyObject *);
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@ -321,6 +321,27 @@ class DictTest(unittest.TestCase):
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self.assertEqual(hashed2.hash_count, 1)
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self.assertEqual(hashed1.eq_count + hashed2.eq_count, 1)
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def test_setitem_atomic_at_resize(self):
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class Hashed(object):
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def __init__(self):
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self.hash_count = 0
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self.eq_count = 0
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def __hash__(self):
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self.hash_count += 1
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return 42
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def __eq__(self, other):
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self.eq_count += 1
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return id(self) == id(other)
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hashed1 = Hashed()
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# 5 items
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y = {hashed1: 5, 0: 0, 1: 1, 2: 2, 3: 3}
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hashed2 = Hashed()
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# 6th item forces a resize
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y[hashed2] = []
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self.assertEqual(hashed1.hash_count, 1)
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self.assertEqual(hashed2.hash_count, 1)
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self.assertEqual(hashed1.eq_count + hashed2.eq_count, 1)
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def test_popitem(self):
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# dict.popitem()
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for copymode in -1, +1:
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@ -219,6 +219,8 @@ class QueryTestCase(unittest.TestCase):
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others.should.not.be: like.this}"""
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self.assertEqual(DottedPrettyPrinter().pformat(o), exp)
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@unittest.expectedFailure
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#See http://bugs.python.org/issue13907
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@test.support.cpython_only
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def test_set_reprs(self):
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# This test creates a complex arrangement of frozensets and
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@ -241,10 +243,12 @@ class QueryTestCase(unittest.TestCase):
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# Consequently, this test is fragile and
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# implementation-dependent. Small changes to Python's sort
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# algorithm cause the test to fail when it should pass.
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# XXX Or changes to the dictionary implmentation...
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self.assertEqual(pprint.pformat(set()), 'set()')
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self.assertEqual(pprint.pformat(set(range(3))), '{0, 1, 2}')
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self.assertEqual(pprint.pformat(frozenset()), 'frozenset()')
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self.assertEqual(pprint.pformat(frozenset(range(3))), 'frozenset({0, 1, 2})')
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cube_repr_tgt = """\
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{frozenset(): frozenset({frozenset({2}), frozenset({0}), frozenset({1})}),
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@ -687,9 +687,9 @@ class SizeofTest(unittest.TestCase):
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# method-wrapper (descriptor object)
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check({}.__iter__, size(h + '2P'))
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# dict
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check({}, size(h + '3P2P' + 8*'P2P'))
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check({}, size(h + '3P' + '4P' + 8*'P2P'))
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longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8}
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check(longdict, size(h + '3P2P' + 8*'P2P') + 16*size('P2P'))
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check(longdict, size(h + '3P' + '4P') + 16*size('P2P'))
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# dictionary-keyiterator
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check({}.keys(), size(h + 'P'))
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# dictionary-valueiterator
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# type
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# (PyTypeObject + PyNumberMethods + PyMappingMethods +
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# PySequenceMethods + PyBufferProcs)
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s = size(vh + 'P2P15Pl4PP9PP11PI') + size('16Pi17P 3P 10P 2P 3P')
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s = size(vh + 'P2P15Pl4PP9PP11PIP') + size('16Pi17P 3P 10P 2P 3P')
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check(int, s)
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# class
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class newstyleclass(object): pass
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@ -10,6 +10,10 @@ What's New in Python 3.3.0 Alpha 3?
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Core and Builtins
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-----------------
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- Issue #13903: Implement PEP 412. Individual dictionary instances can now share
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their keys with other dictionaries. Classes take advantage of this to share
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their instance dictionary keys for improved memory and performance.
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- Issue #14630: Fix a memory access bug for instances of a subclass of int
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with value 0.
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@ -1,7 +1,6 @@
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NOTES ON OPTIMIZING DICTIONARIES
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NOTES ON DICTIONARIES
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================================
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Principal Use Cases for Dictionaries
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------------------------------------
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@ -21,7 +20,7 @@ Instance attribute lookup and Global variables
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Builtins
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Frequent reads. Almost never written.
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Size 126 interned strings (as of Py2.3b1).
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About 150 interned strings (as of Py3.3).
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A few keys are accessed much more frequently than others.
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Uniquification
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@ -59,44 +58,43 @@ Dynamic Mappings
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Characterized by deletions interspersed with adds and replacements.
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Performance benefits greatly from the re-use of dummy entries.
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Data Layout
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-----------
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Data Layout (assuming a 32-bit box with 64 bytes per cache line)
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----------------------------------------------------------------
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Smalldicts (8 entries) are attached to the dictobject structure
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and the whole group nearly fills two consecutive cache lines.
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Larger dicts use the first half of the dictobject structure (one cache
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line) and a separate, continuous block of entries (at 12 bytes each
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for a total of 5.333 entries per cache line).
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Dictionaries are composed of 3 components:
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The dictobject struct itself
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A dict-keys object (keys & hashes)
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A values array
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Tunable Dictionary Parameters
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-----------------------------
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* PyDict_MINSIZE. Currently set to 8.
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Must be a power of two. New dicts have to zero-out every cell.
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Each additional 8 consumes 1.5 cache lines. Increasing improves
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the sparseness of small dictionaries but costs time to read in
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the additional cache lines if they are not already in cache.
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That case is common when keyword arguments are passed.
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* PyDict_STARTSIZE. Starting size of dict (unless an instance dict).
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Currently set to 8. Must be a power of two.
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New dicts have to zero-out every cell.
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Increasing improves the sparseness of small dictionaries but costs
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time to read in the additional cache lines if they are not already
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in cache. That case is common when keyword arguments are passed.
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Prior to version 3.3, PyDict_MINSIZE was used as the starting size
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of a new dict.
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* Maximum dictionary load in PyDict_SetItem. Currently set to 2/3.
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Increasing this ratio makes dictionaries more dense resulting
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in more collisions. Decreasing it improves sparseness at the
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expense of spreading entries over more cache lines and at the
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* PyDict_MINSIZE. Minimum size of a dict.
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Currently set to 4 (to keep instance dicts small).
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Must be a power of two. Prior to version 3.3, PyDict_MINSIZE was
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set to 8.
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* USABLE_FRACTION. Maximum dictionary load in PyDict_SetItem.
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Currently set to 2/3. Increasing this ratio makes dictionaries more
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dense resulting in more collisions. Decreasing it improves sparseness
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at the expense of spreading entries over more cache lines and at the
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cost of total memory consumed.
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The load test occurs in highly time sensitive code. Efforts
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to make the test more complex (for example, varying the load
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for different sizes) have degraded performance.
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* Growth rate upon hitting maximum load. Currently set to *2.
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Raising this to *4 results in half the number of resizes,
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less effort to resize, better sparseness for some (but not
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all dict sizes), and potentially doubles memory consumption
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depending on the size of the dictionary. Setting to *4
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eliminates every other resize step.
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Raising this to *4 results in half the number of resizes, less
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effort to resize, better sparseness for some (but not all dict sizes),
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and potentially doubles memory consumption depending on the size of
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the dictionary. Setting to *4 eliminates every other resize step.
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* Maximum sparseness (minimum dictionary load). What percentage
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of entries can be unused before the dictionary shrinks to
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@ -135,136 +133,51 @@ by repeatedly invoking .pop will see no resizing, which might
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not be necessary at all because the dictionary is eventually
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discarded entirely.
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The key differences between this implementation and earlier versions are:
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1. The table can be split into two parts, the keys and the values.
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2. There is an additional key-value combination: (key, NULL).
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Unlike (<dummy>, NULL) which represents a deleted value, (key, NULL)
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represented a yet to be inserted value. This combination can only occur
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when the table is split.
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3. No small table embedded in the dict,
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as this would make sharing of key-tables impossible.
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These changes have the following consequences.
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1. General dictionaries are slightly larger.
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2. All object dictionaries of a single class can share a single key-table,
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saving about 60% memory for such cases.
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Results of Cache Locality Experiments
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-------------------------------------
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--------------------------------------
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When an entry is retrieved from memory, 4.333 adjacent entries are also
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retrieved into a cache line. Since accessing items in cache is *much*
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cheaper than a cache miss, an enticing idea is to probe the adjacent
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entries as a first step in collision resolution. Unfortunately, the
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introduction of any regularity into collision searches results in more
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collisions than the current random chaining approach.
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Experiments on an earlier design of dictionary, in which all tables were
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combined, showed the following:
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Exploiting cache locality at the expense of additional collisions fails
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to payoff when the entries are already loaded in cache (the expense
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is paid with no compensating benefit). This occurs in small dictionaries
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where the whole dictionary fits into a pair of cache lines. It also
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occurs frequently in large dictionaries which have a common access pattern
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where some keys are accessed much more frequently than others. The
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more popular entries *and* their collision chains tend to remain in cache.
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When an entry is retrieved from memory, several adjacent entries are also
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retrieved into a cache line. Since accessing items in cache is *much*
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cheaper than a cache miss, an enticing idea is to probe the adjacent
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entries as a first step in collision resolution. Unfortunately, the
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introduction of any regularity into collision searches results in more
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collisions than the current random chaining approach.
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To exploit cache locality, change the collision resolution section
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in lookdict() and lookdict_string(). Set i^=1 at the top of the
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loop and move the i = (i << 2) + i + perturb + 1 to an unrolled
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version of the loop.
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Exploiting cache locality at the expense of additional collisions fails
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to payoff when the entries are already loaded in cache (the expense
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is paid with no compensating benefit). This occurs in small dictionaries
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where the whole dictionary fits into a pair of cache lines. It also
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occurs frequently in large dictionaries which have a common access pattern
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where some keys are accessed much more frequently than others. The
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more popular entries *and* their collision chains tend to remain in cache.
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This optimization strategy can be leveraged in several ways:
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To exploit cache locality, change the collision resolution section
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in lookdict() and lookdict_string(). Set i^=1 at the top of the
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loop and move the i = (i << 2) + i + perturb + 1 to an unrolled
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version of the loop.
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* If the dictionary is kept sparse (through the tunable parameters),
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then the occurrence of additional collisions is lessened.
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* If lookdict() and lookdict_string() are specialized for small dicts
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and for largedicts, then the versions for large_dicts can be given
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an alternate search strategy without increasing collisions in small dicts
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which already have the maximum benefit of cache locality.
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* If the use case for a dictionary is known to have a random key
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access pattern (as opposed to a more common pattern with a Zipf's law
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distribution), then there will be more benefit for large dictionaries
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because any given key is no more likely than another to already be
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in cache.
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* In use cases with paired accesses to the same key, the second access
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is always in cache and gets no benefit from efforts to further improve
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cache locality.
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Optimizing the Search of Small Dictionaries
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-------------------------------------------
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If lookdict() and lookdict_string() are specialized for smaller dictionaries,
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then a custom search approach can be implemented that exploits the small
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search space and cache locality.
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* The simplest example is a linear search of contiguous entries. This is
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simple to implement, guaranteed to terminate rapidly, never searches
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the same entry twice, and precludes the need to check for dummy entries.
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* A more advanced example is a self-organizing search so that the most
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frequently accessed entries get probed first. The organization
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adapts if the access pattern changes over time. Treaps are ideally
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suited for self-organization with the most common entries at the
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top of the heap and a rapid binary search pattern. Most probes and
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results are all located at the top of the tree allowing them all to
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be located in one or two cache lines.
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* Also, small dictionaries may be made more dense, perhaps filling all
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eight cells to take the maximum advantage of two cache lines.
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For split tables, the above will apply to the keys, but the value will
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always be in a different cache line from the key.
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||||
Strategy Pattern
|
||||
----------------
|
||||
|
||||
Consider allowing the user to set the tunable parameters or to select a
|
||||
particular search method. Since some dictionary use cases have known
|
||||
sizes and access patterns, the user may be able to provide useful hints.
|
||||
|
||||
1) For example, if membership testing or lookups dominate runtime and memory
|
||||
is not at a premium, the user may benefit from setting the maximum load
|
||||
ratio at 5% or 10% instead of the usual 66.7%. This will sharply
|
||||
curtail the number of collisions but will increase iteration time.
|
||||
The builtin namespace is a prime example of a dictionary that can
|
||||
benefit from being highly sparse.
|
||||
|
||||
2) Dictionary creation time can be shortened in cases where the ultimate
|
||||
size of the dictionary is known in advance. The dictionary can be
|
||||
pre-sized so that no resize operations are required during creation.
|
||||
Not only does this save resizes, but the key insertion will go
|
||||
more quickly because the first half of the keys will be inserted into
|
||||
a more sparse environment than before. The preconditions for this
|
||||
strategy arise whenever a dictionary is created from a key or item
|
||||
sequence and the number of *unique* keys is known.
|
||||
|
||||
3) If the key space is large and the access pattern is known to be random,
|
||||
then search strategies exploiting cache locality can be fruitful.
|
||||
The preconditions for this strategy arise in simulations and
|
||||
numerical analysis.
|
||||
|
||||
4) If the keys are fixed and the access pattern strongly favors some of
|
||||
the keys, then the entries can be stored contiguously and accessed
|
||||
with a linear search or treap. This exploits knowledge of the data,
|
||||
cache locality, and a simplified search routine. It also eliminates
|
||||
the need to test for dummy entries on each probe. The preconditions
|
||||
for this strategy arise in symbol tables and in the builtin dictionary.
|
||||
|
||||
|
||||
Readonly Dictionaries
|
||||
---------------------
|
||||
Some dictionary use cases pass through a build stage and then move to a
|
||||
more heavily exercised lookup stage with no further changes to the
|
||||
dictionary.
|
||||
|
||||
An idea that emerged on python-dev is to be able to convert a dictionary
|
||||
to a read-only state. This can help prevent programming errors and also
|
||||
provide knowledge that can be exploited for lookup optimization.
|
||||
|
||||
The dictionary can be immediately rebuilt (eliminating dummy entries),
|
||||
resized (to an appropriate level of sparseness), and the keys can be
|
||||
jostled (to minimize collisions). The lookdict() routine can then
|
||||
eliminate the test for dummy entries (saving about 1/4 of the time
|
||||
spent in the collision resolution loop).
|
||||
|
||||
An additional possibility is to insert links into the empty spaces
|
||||
so that dictionary iteration can proceed in len(d) steps instead of
|
||||
(mp->mask + 1) steps. Alternatively, a separate tuple of keys can be
|
||||
kept just for iteration.
|
||||
|
||||
|
||||
Caching Lookups
|
||||
---------------
|
||||
The idea is to exploit key access patterns by anticipating future lookups
|
||||
based on previous lookups.
|
||||
|
||||
The simplest incarnation is to save the most recently accessed entry.
|
||||
This gives optimal performance for use cases where every get is followed
|
||||
by a set or del to the same key.
|
||||
|
|
1771
Objects/dictobject.c
1771
Objects/dictobject.c
File diff suppressed because it is too large
Load Diff
|
@ -1188,13 +1188,10 @@ _PyObject_GenericSetAttrWithDict(PyObject *obj, PyObject *name,
|
|||
if (dict == NULL) {
|
||||
dictptr = _PyObject_GetDictPtr(obj);
|
||||
if (dictptr != NULL) {
|
||||
dict = *dictptr;
|
||||
if (dict == NULL && value != NULL) {
|
||||
dict = PyDict_New();
|
||||
if (dict == NULL)
|
||||
goto done;
|
||||
*dictptr = dict;
|
||||
}
|
||||
res = _PyObjectDict_SetItem(Py_TYPE(obj), dictptr, name, value);
|
||||
if (res < 0 && PyErr_ExceptionMatches(PyExc_KeyError))
|
||||
PyErr_SetObject(PyExc_AttributeError, name);
|
||||
goto done;
|
||||
}
|
||||
}
|
||||
if (dict != NULL) {
|
||||
|
@ -1236,22 +1233,6 @@ PyObject_GenericSetAttr(PyObject *obj, PyObject *name, PyObject *value)
|
|||
return _PyObject_GenericSetAttrWithDict(obj, name, value, NULL);
|
||||
}
|
||||
|
||||
PyObject *
|
||||
PyObject_GenericGetDict(PyObject *obj, void *context)
|
||||
{
|
||||
PyObject *dict, **dictptr = _PyObject_GetDictPtr(obj);
|
||||
if (dictptr == NULL) {
|
||||
PyErr_SetString(PyExc_AttributeError,
|
||||
"This object has no __dict__");
|
||||
return NULL;
|
||||
}
|
||||
dict = *dictptr;
|
||||
if (dict == NULL)
|
||||
*dictptr = dict = PyDict_New();
|
||||
Py_XINCREF(dict);
|
||||
return dict;
|
||||
}
|
||||
|
||||
int
|
||||
PyObject_GenericSetDict(PyObject *obj, PyObject *value, void *context)
|
||||
{
|
||||
|
|
|
@ -14,7 +14,7 @@
|
|||
MCACHE_MAX_ATTR_SIZE, since it might be a problem if very large
|
||||
strings are used as attribute names. */
|
||||
#define MCACHE_MAX_ATTR_SIZE 100
|
||||
#define MCACHE_SIZE_EXP 10
|
||||
#define MCACHE_SIZE_EXP 9
|
||||
#define MCACHE_HASH(version, name_hash) \
|
||||
(((unsigned int)(version) * (unsigned int)(name_hash)) \
|
||||
>> (8*sizeof(unsigned int) - MCACHE_SIZE_EXP))
|
||||
|
@ -2306,6 +2306,9 @@ type_new(PyTypeObject *metatype, PyObject *args, PyObject *kwds)
|
|||
type->tp_dictoffset = slotoffset;
|
||||
slotoffset += sizeof(PyObject *);
|
||||
}
|
||||
if (type->tp_dictoffset) {
|
||||
et->ht_cached_keys = _PyDict_NewKeysForClass();
|
||||
}
|
||||
if (add_weak) {
|
||||
assert(!base->tp_itemsize);
|
||||
type->tp_weaklistoffset = slotoffset;
|
||||
|
@ -2411,6 +2414,9 @@ PyType_FromSpec(PyType_Spec *spec)
|
|||
res->ht_type.tp_doc = tp_doc;
|
||||
}
|
||||
}
|
||||
if (res->ht_type.tp_dictoffset) {
|
||||
res->ht_cached_keys = _PyDict_NewKeysForClass();
|
||||
}
|
||||
|
||||
if (PyType_Ready(&res->ht_type) < 0)
|
||||
goto fail;
|
||||
|
@ -2767,9 +2773,13 @@ type_traverse(PyTypeObject *type, visitproc visit, void *arg)
|
|||
return 0;
|
||||
}
|
||||
|
||||
extern void
|
||||
_PyDictKeys_DecRef(PyDictKeysObject *keys);
|
||||
|
||||
static int
|
||||
type_clear(PyTypeObject *type)
|
||||
{
|
||||
PyDictKeysObject *cached_keys;
|
||||
/* Because of type_is_gc(), the collector only calls this
|
||||
for heaptypes. */
|
||||
assert(type->tp_flags & Py_TPFLAGS_HEAPTYPE);
|
||||
|
@ -2801,6 +2811,11 @@ type_clear(PyTypeObject *type)
|
|||
*/
|
||||
|
||||
PyType_Modified(type);
|
||||
cached_keys = ((PyHeapTypeObject *)type)->ht_cached_keys;
|
||||
if (cached_keys != NULL) {
|
||||
((PyHeapTypeObject *)type)->ht_cached_keys = NULL;
|
||||
_PyDictKeys_DecRef(cached_keys);
|
||||
}
|
||||
if (type->tp_dict)
|
||||
PyDict_Clear(type->tp_dict);
|
||||
Py_CLEAR(type->tp_mro);
|
||||
|
|
|
@ -2123,70 +2123,31 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag)
|
|||
w = GETITEM(names, oparg);
|
||||
if (PyDict_CheckExact(f->f_globals)
|
||||
&& PyDict_CheckExact(f->f_builtins)) {
|
||||
if (PyUnicode_CheckExact(w)) {
|
||||
/* Inline the PyDict_GetItem() calls.
|
||||
WARNING: this is an extreme speed hack.
|
||||
Do not try this at home. */
|
||||
Py_hash_t hash = ((PyASCIIObject *)w)->hash;
|
||||
if (hash != -1) {
|
||||
PyDictObject *d;
|
||||
PyDictEntry *e;
|
||||
d = (PyDictObject *)(f->f_globals);
|
||||
e = d->ma_lookup(d, w, hash);
|
||||
if (e == NULL) {
|
||||
x = NULL;
|
||||
break;
|
||||
}
|
||||
x = e->me_value;
|
||||
if (x != NULL) {
|
||||
Py_INCREF(x);
|
||||
PUSH(x);
|
||||
DISPATCH();
|
||||
}
|
||||
d = (PyDictObject *)(f->f_builtins);
|
||||
e = d->ma_lookup(d, w, hash);
|
||||
if (e == NULL) {
|
||||
x = NULL;
|
||||
break;
|
||||
}
|
||||
x = e->me_value;
|
||||
if (x != NULL) {
|
||||
Py_INCREF(x);
|
||||
PUSH(x);
|
||||
DISPATCH();
|
||||
}
|
||||
goto load_global_error;
|
||||
}
|
||||
}
|
||||
/* This is the un-inlined version of the code above */
|
||||
x = PyDict_GetItem(f->f_globals, w);
|
||||
x = _PyDict_LoadGlobal((PyDictObject *)f->f_globals,
|
||||
(PyDictObject *)f->f_builtins,
|
||||
w);
|
||||
if (x == NULL) {
|
||||
x = PyDict_GetItem(f->f_builtins, w);
|
||||
if (x == NULL) {
|
||||
load_global_error:
|
||||
format_exc_check_arg(
|
||||
PyExc_NameError,
|
||||
GLOBAL_NAME_ERROR_MSG, w);
|
||||
break;
|
||||
}
|
||||
}
|
||||
Py_INCREF(x);
|
||||
PUSH(x);
|
||||
DISPATCH();
|
||||
}
|
||||
|
||||
/* Slow-path if globals or builtins is not a dict */
|
||||
x = PyObject_GetItem(f->f_globals, w);
|
||||
if (x == NULL) {
|
||||
x = PyObject_GetItem(f->f_builtins, w);
|
||||
if (x == NULL) {
|
||||
if (PyErr_ExceptionMatches(PyExc_KeyError))
|
||||
format_exc_check_arg(
|
||||
PyExc_NameError,
|
||||
GLOBAL_NAME_ERROR_MSG, w);
|
||||
if (!PyErr_Occurred())
|
||||
format_exc_check_arg(PyExc_NameError,
|
||||
GLOBAL_NAME_ERROR_MSG, w);
|
||||
break;
|
||||
}
|
||||
}
|
||||
else {
|
||||
/* Slow-path if globals or builtins is not a dict */
|
||||
x = PyObject_GetItem(f->f_globals, w);
|
||||
if (x == NULL) {
|
||||
x = PyObject_GetItem(f->f_builtins, w);
|
||||
if (x == NULL) {
|
||||
if (PyErr_ExceptionMatches(PyExc_KeyError))
|
||||
format_exc_check_arg(
|
||||
PyExc_NameError,
|
||||
GLOBAL_NAME_ERROR_MSG, w);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
Py_INCREF(x);
|
||||
PUSH(x);
|
||||
DISPATCH();
|
||||
|
||||
|
|
|
@ -634,9 +634,14 @@ class PyDictObjectPtr(PyObjectPtr):
|
|||
Yields a sequence of (PyObjectPtr key, PyObjectPtr value) pairs,
|
||||
analagous to dict.iteritems()
|
||||
'''
|
||||
for i in safe_range(self.field('ma_mask') + 1):
|
||||
ep = self.field('ma_table') + i
|
||||
pyop_value = PyObjectPtr.from_pyobject_ptr(ep['me_value'])
|
||||
keys = self.field('ma_keys')
|
||||
values = self.field('ma_values')
|
||||
for i in safe_range(keys['dk_size']):
|
||||
ep = keys['dk_entries'].address + i
|
||||
if long(values):
|
||||
pyop_value = PyObjectPtr.from_pyobject_ptr(values[i])
|
||||
else:
|
||||
pyop_value = PyObjectPtr.from_pyobject_ptr(ep['me_value'])
|
||||
if not pyop_value.is_null():
|
||||
pyop_key = PyObjectPtr.from_pyobject_ptr(ep['me_key'])
|
||||
yield (pyop_key, pyop_value)
|
||||
|
|
Loading…
Reference in New Issue