Optionally measure size of cache by sum of length of values

This commit is contained in:
Erik Johnston 2017-01-13 17:46:17 +00:00
parent 95a22ae194
commit 2fae34bd2c
5 changed files with 66 additions and 21 deletions

View File

@ -390,7 +390,8 @@ class RoomMemberStore(SQLBaseStore):
room_id, state_group, state_ids, room_id, state_group, state_ids,
) )
@cachedInlineCallbacks(num_args=2, cache_context=True) @cachedInlineCallbacks(num_args=2, cache_context=True, iterable=True,
max_entries=2000)
def _get_joined_users_from_context(self, room_id, state_group, current_state_ids, def _get_joined_users_from_context(self, room_id, state_group, current_state_ids,
cache_context, event=None): cache_context, event=None):
# We don't use `state_group`, it's there so that we can cache based # We don't use `state_group`, it's there so that we can cache based

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@ -284,7 +284,7 @@ class StateStore(SQLBaseStore):
return [r[0] for r in results] return [r[0] for r in results]
return self.runInteraction("get_current_state_for_key", f) return self.runInteraction("get_current_state_for_key", f)
@cached(num_args=2, max_entries=1000) @cached(num_args=2, max_entries=1000, iterable=True)
def _get_state_group_from_group(self, group, types): def _get_state_group_from_group(self, group, types):
raise NotImplementedError() raise NotImplementedError()

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@ -42,6 +42,13 @@ _CacheSentinel = object()
CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.1)) CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.1))
def deferred_size(deferred):
if deferred.called:
return len(deferred.result)
else:
return 1
class Cache(object): class Cache(object):
__slots__ = ( __slots__ = (
"cache", "cache",
@ -53,10 +60,11 @@ class Cache(object):
"metrics", "metrics",
) )
def __init__(self, name, max_entries=1000, keylen=1, tree=False): def __init__(self, name, max_entries=1000, keylen=1, tree=False, iterable=False):
cache_type = TreeCache if tree else dict cache_type = TreeCache if tree else dict
self.cache = LruCache( self.cache = LruCache(
max_size=max_entries, keylen=keylen, cache_type=cache_type max_size=max_entries, keylen=keylen, cache_type=cache_type,
size_callback=deferred_size if iterable else None,
) )
self.name = name self.name = name
@ -155,7 +163,7 @@ class CacheDescriptor(object):
""" """
def __init__(self, orig, max_entries=1000, num_args=1, tree=False, def __init__(self, orig, max_entries=1000, num_args=1, tree=False,
inlineCallbacks=False, cache_context=False): inlineCallbacks=False, cache_context=False, iterable=False):
max_entries = int(max_entries * CACHE_SIZE_FACTOR) max_entries = int(max_entries * CACHE_SIZE_FACTOR)
self.orig = orig self.orig = orig
@ -169,6 +177,8 @@ class CacheDescriptor(object):
self.num_args = num_args self.num_args = num_args
self.tree = tree self.tree = tree
self.iterable = iterable
all_args = inspect.getargspec(orig) all_args = inspect.getargspec(orig)
self.arg_names = all_args.args[1:num_args + 1] self.arg_names = all_args.args[1:num_args + 1]
@ -203,6 +213,7 @@ class CacheDescriptor(object):
max_entries=self.max_entries, max_entries=self.max_entries,
keylen=self.num_args, keylen=self.num_args,
tree=self.tree, tree=self.tree,
iterable=self.iterable,
) )
@functools.wraps(self.orig) @functools.wraps(self.orig)
@ -421,17 +432,20 @@ class _CacheContext(namedtuple("_CacheContext", ("cache", "key"))):
self.cache.invalidate(self.key) self.cache.invalidate(self.key)
def cached(max_entries=1000, num_args=1, tree=False, cache_context=False): def cached(max_entries=1000, num_args=1, tree=False, cache_context=False,
iterable=False):
return lambda orig: CacheDescriptor( return lambda orig: CacheDescriptor(
orig, orig,
max_entries=max_entries, max_entries=max_entries,
num_args=num_args, num_args=num_args,
tree=tree, tree=tree,
cache_context=cache_context, cache_context=cache_context,
iterable=iterable,
) )
def cachedInlineCallbacks(max_entries=1000, num_args=1, tree=False, cache_context=False): def cachedInlineCallbacks(max_entries=1000, num_args=1, tree=False, cache_context=False,
iterable=False):
return lambda orig: CacheDescriptor( return lambda orig: CacheDescriptor(
orig, orig,
max_entries=max_entries, max_entries=max_entries,
@ -439,6 +453,7 @@ def cachedInlineCallbacks(max_entries=1000, num_args=1, tree=False, cache_contex
tree=tree, tree=tree,
inlineCallbacks=True, inlineCallbacks=True,
cache_context=cache_context, cache_context=cache_context,
iterable=iterable,
) )

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@ -49,7 +49,7 @@ class LruCache(object):
Can also set callbacks on objects when getting/setting which are fired Can also set callbacks on objects when getting/setting which are fired
when that key gets invalidated/evicted. when that key gets invalidated/evicted.
""" """
def __init__(self, max_size, keylen=1, cache_type=dict): def __init__(self, max_size, keylen=1, cache_type=dict, size_callback=None):
cache = cache_type() cache = cache_type()
self.cache = cache # Used for introspection. self.cache = cache # Used for introspection.
list_root = _Node(None, None, None, None) list_root = _Node(None, None, None, None)
@ -58,6 +58,18 @@ class LruCache(object):
lock = threading.Lock() lock = threading.Lock()
def cache_len():
if size_callback is not None:
return sum(size_callback(node.value) for node in cache.itervalues())
else:
return len(cache)
def evict():
while cache_len() > max_size:
todelete = list_root.prev_node
delete_node(todelete)
cache.pop(todelete.key, None)
def synchronized(f): def synchronized(f):
@wraps(f) @wraps(f)
def inner(*args, **kwargs): def inner(*args, **kwargs):
@ -127,22 +139,18 @@ class LruCache(object):
else: else:
callbacks = set() callbacks = set()
add_node(key, value, callbacks) add_node(key, value, callbacks)
if len(cache) > max_size:
todelete = list_root.prev_node evict()
delete_node(todelete)
cache.pop(todelete.key, None)
@synchronized @synchronized
def cache_set_default(key, value): def cache_set_default(key, value):
node = cache.get(key, None) node = cache.get(key, None)
if node is not None: if node is not None:
evict() # As the new node may be bigger than the old node.
return node.value return node.value
else: else:
add_node(key, value) add_node(key, value)
if len(cache) > max_size: evict()
todelete = list_root.prev_node
delete_node(todelete)
cache.pop(todelete.key, None)
return value return value
@synchronized @synchronized
@ -175,10 +183,6 @@ class LruCache(object):
cb() cb()
cache.clear() cache.clear()
@synchronized
def cache_len():
return len(cache)
@synchronized @synchronized
def cache_contains(key): def cache_contains(key):
return key in cache return key in cache
@ -190,7 +194,7 @@ class LruCache(object):
self.pop = cache_pop self.pop = cache_pop
if cache_type is TreeCache: if cache_type is TreeCache:
self.del_multi = cache_del_multi self.del_multi = cache_del_multi
self.len = cache_len self.len = synchronized(cache_len)
self.contains = cache_contains self.contains = cache_contains
self.clear = cache_clear self.clear = cache_clear

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@ -232,3 +232,28 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
self.assertEquals(m1.call_count, 1) self.assertEquals(m1.call_count, 1)
self.assertEquals(m2.call_count, 0) self.assertEquals(m2.call_count, 0)
self.assertEquals(m3.call_count, 1) self.assertEquals(m3.call_count, 1)
class LruCacheSizedTestCase(unittest.TestCase):
def test_evict(self):
cache = LruCache(5, size_callback=len)
cache["key1"] = [0]
cache["key2"] = [1, 2]
cache["key3"] = [3]
cache["key4"] = [4]
self.assertEquals(cache["key1"], [0])
self.assertEquals(cache["key2"], [1, 2])
self.assertEquals(cache["key3"], [3])
self.assertEquals(cache["key4"], [4])
self.assertEquals(len(cache), 5)
cache["key5"] = [5, 6]
self.assertEquals(len(cache), 4)
self.assertEquals(cache.get("key1"), None)
self.assertEquals(cache.get("key2"), None)
self.assertEquals(cache["key3"], [3])
self.assertEquals(cache["key4"], [4])
self.assertEquals(cache["key5"], [5, 6])