_tracemalloc: use compact key for traces

Issue #26588: Optimize memory footprint of _tracemalloc before non-zero domain
is used. Start with compact key (Py_uintptr_t) and also switch to pointer_t key
when the first memory block with a non-zero domain is tracked.
This commit is contained in:
Victor Stinner 2016-03-23 22:03:55 +01:00
parent cc73932125
commit 5e14a38e8e
1 changed files with 61 additions and 1 deletions

View File

@ -43,7 +43,7 @@ static struct {
/* use domain in trace key?
Variable protected by the GIL. */
int use_domain;
} tracemalloc_config = {TRACEMALLOC_NOT_INITIALIZED, 0, 1, 1};
} tracemalloc_config = {TRACEMALLOC_NOT_INITIALIZED, 0, 1, 0};
#if defined(TRACE_RAW_MALLOC) && defined(WITH_THREAD)
/* This lock is needed because tracemalloc_free() is called without
@ -519,6 +519,58 @@ traceback_new(void)
}
static int
tracemalloc_use_domain_cb(_Py_hashtable_t *old_traces,
_Py_hashtable_entry_t *entry, void *user_data)
{
Py_uintptr_t ptr;
pointer_t key;
_Py_hashtable_t *new_traces = (_Py_hashtable_t *)user_data;
const void *pdata = _Py_HASHTABLE_ENTRY_PDATA(old_traces, entry);
_Py_HASHTABLE_ENTRY_READ_KEY(old_traces, entry, ptr);
key.ptr = ptr;
key.domain = DEFAULT_DOMAIN;
return _Py_hashtable_set(new_traces,
sizeof(key), &key,
old_traces->data_size, pdata);
}
/* Convert tracemalloc_traces from compact key (Py_uintptr_t) to pointer_t key.
* Return 0 on success, -1 on error. */
static int
tracemalloc_use_domain(void)
{
_Py_hashtable_t *new_traces = NULL;
assert(!tracemalloc_config.use_domain);
new_traces = hashtable_new(sizeof(pointer_t),
sizeof(trace_t),
hashtable_hash_pointer_t,
hashtable_compare_pointer_t);
if (new_traces == NULL) {
return -1;
}
if (_Py_hashtable_foreach(tracemalloc_traces, tracemalloc_use_domain_cb,
new_traces) < 0)
{
_Py_hashtable_destroy(new_traces);
return -1;
}
_Py_hashtable_destroy(tracemalloc_traces);
tracemalloc_traces = new_traces;
tracemalloc_config.use_domain = 1;
return 0;
}
static void
tracemalloc_remove_trace(_PyTraceMalloc_domain_t domain, Py_uintptr_t ptr)
{
@ -563,6 +615,14 @@ tracemalloc_add_trace(_PyTraceMalloc_domain_t domain, Py_uintptr_t ptr,
return -1;
}
if (!tracemalloc_config.use_domain && domain != DEFAULT_DOMAIN) {
/* first trace using a non-zero domain whereas traces use compact
(Py_uintptr_t) keys: switch to pointer_t keys. */
if (tracemalloc_use_domain() < 0) {
return -1;
}
}
if (tracemalloc_config.use_domain) {
entry = _Py_HASHTABLE_GET_ENTRY(tracemalloc_traces, key);
}