diff options
Diffstat (limited to 'Objects/listobject.c')
| -rw-r--r-- | Objects/listobject.c | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/Objects/listobject.c b/Objects/listobject.c index cb0609ac4d7..d2917d2caa9 100644 --- a/Objects/listobject.c +++ b/Objects/listobject.c @@ -63,6 +63,22 @@ list_resize(PyListObject *self, Py_ssize_t newsize) return 0; } +/* Debug statistic to compare allocations with reuse through the free list */ +#undef SHOW_ALLOC_COUNT +#ifdef SHOW_ALLOC_COUNT +static size_t count_alloc = 0; +static size_t count_reuse = 0; + +static void +show_alloc(void) +{ + fprintf(stderr, "List allocations: %zd\n", count_alloc); + fprintf(stderr, "List reuse through freelist: %zd\n", count_reuse); + fprintf(stderr, "%.2f%% reuse rate\n\n", + (100.0*count_reuse/(count_alloc+count_reuse))); +} +#endif + /* Empty list reuse scheme to save calls to malloc and free */ #ifndef PyList_MAXFREELIST #define PyList_MAXFREELIST 80 @@ -76,8 +92,7 @@ PyList_Fini(void) PyListObject *op; while (numfree) { - numfree--; - op = free_list[numfree]; + op = free_list[--numfree]; assert(PyList_CheckExact(op)); PyObject_GC_Del(op); } @@ -88,6 +103,13 @@ PyList_New(Py_ssize_t size) { PyListObject *op; size_t nbytes; +#ifdef SHOW_ALLOC_COUNT + static int initialized = 0; + if (!initialized) { + Py_AtExit(show_alloc); + initialized = 1; + } +#endif if (size < 0) { PyErr_BadInternalCall(); @@ -101,10 +123,16 @@ PyList_New(Py_ssize_t size) numfree--; op = free_list[numfree]; _Py_NewReference((PyObject *)op); +#ifdef SHOW_ALLOC_COUNT + count_reuse++; +#endif } else { op = PyObject_GC_New(PyListObject, &PyList_Type); if (op == NULL) return NULL; +#ifdef SHOW_ALLOC_COUNT + count_alloc++; +#endif } if (size <= 0) op->ob_item = NULL; |