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Merge pull request #1815 from matrix-org/erikj/iter_cache_size

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Optionally measure size of cache by sum of length of values
This commit is contained in:
Erik Johnston 2017-01-17 11:51:09 +00:00 committed by GitHub
commit d11d7cdf87
12 changed files with 308 additions and 85 deletions
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6
synapse/state.py
View File

@ -41,7 +41,7 @@ KeyStateTuple = namedtuple("KeyStateTuple", ("context", "type", "state_key"))
CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.1))
SIZE_OF_CACHE = int(1000 * CACHE_SIZE_FACTOR)
SIZE_OF_CACHE = int(100000 * CACHE_SIZE_FACTOR)
EVICTION_TIMEOUT_SECONDS = 60 * 60
@ -77,6 +77,9 @@ class _StateCacheEntry(object):
else:
self.state_id = _gen_state_id()
def __len__(self):
return len(self.state)
class StateHandler(object):
""" Responsible for doing state conflict resolution.
@ -99,6 +102,7 @@ class StateHandler(object):
clock=self.clock,
max_len=SIZE_OF_CACHE,
expiry_ms=EVICTION_TIMEOUT_SECONDS * 1000,
iterable=True,
reset_expiry_on_get=True,
)

2
synapse/storage/_base.py
View File

@ -169,7 +169,7 @@ class SQLBaseStore(object):
max_entries=hs.config.event_cache_size)
self._state_group_cache = DictionaryCache(
"*stateGroupCache*", 2000 * CACHE_SIZE_FACTOR
"*stateGroupCache*", 100000 * CACHE_SIZE_FACTOR
)
self._event_fetch_lock = threading.Condition()

3
synapse/storage/roommember.py
View File

@ -390,7 +390,8 @@ class RoomMemberStore(SQLBaseStore):
room_id, state_group, state_ids,
)
@cachedInlineCallbacks(num_args=2, cache_context=True)
@cachedInlineCallbacks(num_args=2, cache_context=True, iterable=True,
max_entries=100000)
def _get_joined_users_from_context(self, room_id, state_group, current_state_ids,
cache_context, event=None):
# We don't use `state_group`, it's there so that we can cache based

2
synapse/storage/state.py
View File

@ -284,7 +284,7 @@ class StateStore(SQLBaseStore):
return [r[0] for r in results]
return self.runInteraction("get_current_state_for_key", f)
@cached(num_args=2, max_entries=1000)
@cached(num_args=2, max_entries=100000, iterable=True)
def _get_state_group_from_group(self, group, types):
raise NotImplementedError()

110
synapse/util/caches/descriptors.py
View File

@ -17,7 +17,7 @@ import logging
from synapse.util.async import ObservableDeferred
from synapse.util import unwrapFirstError
from synapse.util.caches.lrucache import LruCache
from synapse.util.caches.treecache import TreeCache
from synapse.util.caches.treecache import TreeCache, iterate_tree_cache_entry
from synapse.util.logcontext import (
PreserveLoggingContext, preserve_context_over_deferred, preserve_context_over_fn
)
@ -42,6 +42,25 @@ _CacheSentinel = object()
CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.1))
class CacheEntry(object):
__slots__ = [
"deferred", "sequence", "callbacks", "invalidated"
]
def __init__(self, deferred, sequence, callbacks):
self.deferred = deferred
self.sequence = sequence
self.callbacks = set(callbacks)
self.invalidated = False
def invalidate(self):
if not self.invalidated:
self.invalidated = True
for callback in self.callbacks:
callback()
self.callbacks.clear()
class Cache(object):
__slots__ = (
"cache",
@ -51,12 +70,16 @@ class Cache(object):
"sequence",
"thread",
"metrics",
"_pending_deferred_cache",
)
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
self._pending_deferred_cache = cache_type()
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=(lambda d: len(d.result)) if iterable else None,
)
self.name = name
@ -76,7 +99,15 @@ class Cache(object):
)
def get(self, key, default=_CacheSentinel, callback=None):
val = self.cache.get(key, _CacheSentinel, callback=callback)
callbacks = [callback] if callback else []
val = self._pending_deferred_cache.get(key, _CacheSentinel)
if val is not _CacheSentinel:
if val.sequence == self.sequence:
val.callbacks.update(callbacks)
self.metrics.inc_hits()
return val.deferred
val = self.cache.get(key, _CacheSentinel, callbacks=callbacks)
if val is not _CacheSentinel:
self.metrics.inc_hits()
return val
@ -88,15 +119,39 @@ class Cache(object):
else:
return default
def update(self, sequence, key, value, callback=None):
def set(self, key, value, callback=None):
callbacks = [callback] if callback else []
self.check_thread()
if self.sequence == sequence:
# Only update the cache if the caches sequence number matches the
# number that the cache had before the SELECT was started (SYN-369)
self.prefill(key, value, callback=callback)
entry = CacheEntry(
deferred=value,
sequence=self.sequence,
callbacks=callbacks,
)
entry.callbacks.update(callbacks)
existing_entry = self._pending_deferred_cache.pop(key, None)
if existing_entry:
existing_entry.invalidate()
self._pending_deferred_cache[key] = entry
def shuffle(result):
if self.sequence == entry.sequence:
existing_entry = self._pending_deferred_cache.pop(key, None)
if existing_entry is entry:
self.cache.set(key, entry.deferred, entry.callbacks)
else:
entry.invalidate()
else:
entry.invalidate()
return result
entry.deferred.addCallback(shuffle)
def prefill(self, key, value, callback=None):
self.cache.set(key, value, callback=callback)
callbacks = [callback] if callback else []
self.cache.set(key, value, callbacks=callbacks)
def invalidate(self, key):
self.check_thread()
@ -108,6 +163,10 @@ class Cache(object):
# Increment the sequence number so that any SELECT statements that
# raced with the INSERT don't update the cache (SYN-369)
self.sequence += 1
entry = self._pending_deferred_cache.pop(key, None)
if entry:
entry.invalidate()
self.cache.pop(key, None)
def invalidate_many(self, key):
@ -119,6 +178,12 @@ class Cache(object):
self.sequence += 1
self.cache.del_multi(key)
val = self._pending_deferred_cache.pop(key, None)
if val is not None:
entry_dict, _ = val
for entry in iterate_tree_cache_entry(entry_dict):
entry.invalidate()
def invalidate_all(self):
self.check_thread()
self.sequence += 1
@ -155,7 +220,7 @@ class CacheDescriptor(object):
"""
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)
self.orig = orig
@ -169,6 +234,8 @@ class CacheDescriptor(object):
self.num_args = num_args
self.tree = tree
self.iterable = iterable
all_args = inspect.getargspec(orig)
self.arg_names = all_args.args[1:num_args + 1]
@ -203,6 +270,7 @@ class CacheDescriptor(object):
max_entries=self.max_entries,
keylen=self.num_args,
tree=self.tree,
iterable=self.iterable,
)
@functools.wraps(self.orig)
@ -243,11 +311,6 @@ class CacheDescriptor(object):
return preserve_context_over_deferred(observer)
except KeyError:
# Get the sequence number of the cache before reading from the
# database so that we can tell if the cache is invalidated
# while the SELECT is executing (SYN-369)
sequence = cache.sequence
ret = defer.maybeDeferred(
preserve_context_over_fn,
self.function_to_call,
@ -261,7 +324,7 @@ class CacheDescriptor(object):
ret.addErrback(onErr)
ret = ObservableDeferred(ret, consumeErrors=True)
cache.update(sequence, cache_key, ret, callback=invalidate_callback)
cache.set(cache_key, ret, callback=invalidate_callback)
return preserve_context_over_deferred(ret.observe())
@ -359,7 +422,6 @@ class CacheListDescriptor(object):
missing.append(arg)
if missing:
sequence = cache.sequence
args_to_call = dict(arg_dict)
args_to_call[self.list_name] = missing
@ -382,8 +444,8 @@ class CacheListDescriptor(object):
key = list(keyargs)
key[self.list_pos] = arg
cache.update(
sequence, tuple(key), observer,
cache.set(
tuple(key), observer,
callback=invalidate_callback
)
@ -421,17 +483,20 @@ class _CacheContext(namedtuple("_CacheContext", ("cache", "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(
orig,
max_entries=max_entries,
num_args=num_args,
tree=tree,
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(
orig,
max_entries=max_entries,
@ -439,6 +504,7 @@ def cachedInlineCallbacks(max_entries=1000, num_args=1, tree=False, cache_contex
tree=tree,
inlineCallbacks=True,
cache_context=cache_context,
iterable=iterable,
)

6
synapse/util/caches/dictionary_cache.py
View File

@ -23,7 +23,9 @@ import logging
logger = logging.getLogger(__name__)
DictionaryEntry = namedtuple("DictionaryEntry", ("full", "value"))
class DictionaryEntry(namedtuple("DictionaryEntry", ("full", "value"))):
def __len__(self):
return len(self.value)
class DictionaryCache(object):
@ -32,7 +34,7 @@ class DictionaryCache(object):
"""
def __init__(self, name, max_entries=1000):
self.cache = LruCache(max_size=max_entries)
self.cache = LruCache(max_size=max_entries, size_callback=len)
self.name = name
self.sequence = 0

39
synapse/util/caches/expiringcache.py
View File

@ -15,6 +15,7 @@
from synapse.util.caches import register_cache
from collections import OrderedDict
import logging
@ -23,7 +24,7 @@ logger = logging.getLogger(__name__)
class ExpiringCache(object):
def __init__(self, cache_name, clock, max_len=0, expiry_ms=0,
reset_expiry_on_get=False):
reset_expiry_on_get=False, iterable=False):
"""
Args:
cache_name (str): Name of this cache, used for logging.
@ -36,6 +37,8 @@ class ExpiringCache(object):
evicted based on time.
reset_expiry_on_get (bool): If true, will reset the expiry time for
an item on access. Defaults to False.
iterable (bool): If true, the size is calculated by summing the
sizes of all entries, rather than the number of entries.
"""
self._cache_name = cache_name
@ -47,9 +50,13 @@ class ExpiringCache(object):
self._reset_expiry_on_get = reset_expiry_on_get
self._cache = {}
self._cache = OrderedDict()
self.metrics = register_cache(cache_name, self._cache)
self.metrics = register_cache(cache_name, self)
self.iterable = iterable
self._size_estimate = 0
def start(self):
if not self._expiry_ms:
@ -65,15 +72,14 @@ class ExpiringCache(object):
now = self._clock.time_msec()
self._cache[key] = _CacheEntry(now, value)
# Evict if there are now too many items
if self._max_len and len(self._cache.keys()) > self._max_len:
sorted_entries = sorted(
self._cache.items(),
key=lambda item: item[1].time,
)
if self.iterable:
self._size_estimate += len(value)
for k, _ in sorted_entries[self._max_len:]:
self._cache.pop(k)
# Evict if there are now too many items
while self._max_len and len(self) > self._max_len:
_key, value = self._cache.popitem(last=False)
if self.iterable:
self._size_estimate -= len(value.value)
def __getitem__(self, key):
try:
@ -99,7 +105,7 @@ class ExpiringCache(object):
# zero expiry time means don't expire. This should never get called
# since we have this check in start too.
return
begin_length = len(self._cache)
begin_length = len(self)
now = self._clock.time_msec()
@ -110,14 +116,19 @@ class ExpiringCache(object):
keys_to_delete.add(key)
for k in keys_to_delete:
self._cache.pop(k)
value = self._cache.pop(k)
if self.iterable:
self._size_estimate -= len(value.value)
logger.debug(
"[%s] _prune_cache before: %d, after len: %d",
self._cache_name, begin_length, len(self._cache)
self._cache_name, begin_length, len(self)
)
def __len__(self):
if self.iterable:
return self._size_estimate
else:
return len(self._cache)

61
synapse/util/caches/lrucache.py
View File

@ -49,7 +49,7 @@ class LruCache(object):
Can also set callbacks on objects when getting/setting which are fired
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()
self.cache = cache # Used for introspection.
list_root = _Node(None, None, None, None)
@ -58,6 +58,12 @@ class LruCache(object):
lock = threading.Lock()
def evict():
while cache_len() > max_size:
todelete = list_root.prev_node
delete_node(todelete)
cache.pop(todelete.key, None)
def synchronized(f):
@wraps(f)
def inner(*args, **kwargs):
@ -66,6 +72,16 @@ class LruCache(object):
return inner
cached_cache_len = [0]
if size_callback is not None:
def cache_len():
return cached_cache_len[0]
else:
def cache_len():
return len(cache)
self.len = synchronized(cache_len)
def add_node(key, value, callbacks=set()):
prev_node = list_root
next_node = prev_node.next_node
@ -74,6 +90,9 @@ class LruCache(object):
next_node.prev_node = node
cache[key] = node
if size_callback:
cached_cache_len[0] += size_callback(node.value)
def move_node_to_front(node):
prev_node = node.prev_node
next_node = node.next_node
@ -92,23 +111,25 @@ class LruCache(object):
prev_node.next_node = next_node
next_node.prev_node = prev_node
if size_callback:
cached_cache_len[0] -= size_callback(node.value)
for cb in node.callbacks:
cb()
node.callbacks.clear()
@synchronized
def cache_get(key, default=None, callback=None):
def cache_get(key, default=None, callbacks=[]):
node = cache.get(key, None)
if node is not None:
move_node_to_front(node)
if callback:
node.callbacks.add(callback)
node.callbacks.update(callbacks)
return node.value
else:
return default
@synchronized
def cache_set(key, value, callback=None):
def cache_set(key, value, callbacks=[]):
node = cache.get(key, None)
if node is not None:
if value != node.value:
@ -116,21 +137,18 @@ class LruCache(object):
cb()
node.callbacks.clear()
if callback:
node.callbacks.add(callback)
if size_callback:
cached_cache_len[0] -= size_callback(node.value)
cached_cache_len[0] += size_callback(value)
node.callbacks.update(callbacks)
move_node_to_front(node)
node.value = value
else:
if callback:
callbacks = set([callback])
else:
callbacks = set()
add_node(key, value, callbacks)
if len(cache) > max_size:
todelete = list_root.prev_node
delete_node(todelete)
cache.pop(todelete.key, None)
add_node(key, value, set(callbacks))
evict()
@synchronized
def cache_set_default(key, value):
@ -139,10 +157,7 @@ class LruCache(object):
return node.value
else:
add_node(key, value)
if len(cache) > max_size:
todelete = list_root.prev_node
delete_node(todelete)
cache.pop(todelete.key, None)
evict()
return value
@synchronized
@ -175,10 +190,6 @@ class LruCache(object):
cb()
cache.clear()
@synchronized
def cache_len():
return len(cache)
@synchronized
def cache_contains(key):
return key in cache
@ -190,7 +201,7 @@ class LruCache(object):
self.pop = cache_pop
if cache_type is TreeCache:
self.del_multi = cache_del_multi
self.len = cache_len
self.len = synchronized(cache_len)
self.contains = cache_contains
self.clear = cache_clear

17
synapse/util/caches/treecache.py
View File

@ -65,12 +65,27 @@ class TreeCache(object):
return popped
def values(self):
return [e.value for e in self.root.values()]
return list(iterate_tree_cache_entry(self.root))
def __len__(self):
return self.size
def iterate_tree_cache_entry(d):
"""Helper function to iterate over the leaves of a tree, i.e. a dict of that
can contain dicts.
"""
if isinstance(d, dict):
for value_d in d.itervalues():
for value in iterate_tree_cache_entry(value_d):
yield value
else:
if isinstance(d, _Entry):
yield d.value
else:
yield d
class _Entry(object):
__slots__ = ["value"]

6
tests/storage/test__base.py
View File

@ -241,7 +241,7 @@ class CacheDecoratorTestCase(unittest.TestCase):
callcount2 = [0]
class A(object):
@cached(max_entries=2)
@cached(max_entries=20) # HACK: This makes it 2 due to cache factor
def func(self, key):
callcount[0] += 1
return key
@ -258,6 +258,10 @@ class CacheDecoratorTestCase(unittest.TestCase):
self.assertEquals(callcount[0], 2)
self.assertEquals(callcount2[0], 2)
yield a.func2("foo")
self.assertEquals(callcount[0], 2)
self.assertEquals(callcount2[0], 2)
yield a.func("foo3")
self.assertEquals(callcount[0], 3)

84
tests/util/test_expiring_cache.py Normal file
View File

@ -0,0 +1,84 @@
# -*- coding: utf-8 -*-
# Copyright 2017 OpenMarket Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from .. import unittest
from synapse.util.caches.expiringcache import ExpiringCache
from tests.utils import MockClock
class ExpiringCacheTestCase(unittest.TestCase):
def test_get_set(self):
clock = MockClock()
cache = ExpiringCache("test", clock, max_len=1)
cache["key"] = "value"
self.assertEquals(cache.get("key"), "value")
self.assertEquals(cache["key"], "value")
def test_eviction(self):
clock = MockClock()
cache = ExpiringCache("test", clock, max_len=2)
cache["key"] = "value"
cache["key2"] = "value2"
self.assertEquals(cache.get("key"), "value")
self.assertEquals(cache.get("key2"), "value2")
cache["key3"] = "value3"
self.assertEquals(cache.get("key"), None)
self.assertEquals(cache.get("key2"), "value2")
self.assertEquals(cache.get("key3"), "value3")
def test_iterable_eviction(self):
clock = MockClock()
cache = ExpiringCache("test", clock, max_len=5, iterable=True)
cache["key"] = [1]
cache["key2"] = [2, 3]
cache["key3"] = [4, 5]
self.assertEquals(cache.get("key"), [1])
self.assertEquals(cache.get("key2"), [2, 3])
self.assertEquals(cache.get("key3"), [4, 5])
cache["key4"] = [6, 7]
self.assertEquals(cache.get("key"), None)
self.assertEquals(cache.get("key2"), None)
self.assertEquals(cache.get("key3"), [4, 5])
self.assertEquals(cache.get("key4"), [6, 7])
def test_time_eviction(self):
clock = MockClock()
cache = ExpiringCache("test", clock, expiry_ms=1000)
cache.start()
cache["key"] = 1
clock.advance_time(0.5)
cache["key2"] = 2
self.assertEquals(cache.get("key"), 1)
self.assertEquals(cache.get("key2"), 2)
clock.advance_time(0.9)
self.assertEquals(cache.get("key"), None)
self.assertEquals(cache.get("key2"), 2)
clock.advance_time(1)
self.assertEquals(cache.get("key"), None)
self.assertEquals(cache.get("key2"), None)

55
tests/util/test_lrucache.py
View File

@ -93,7 +93,7 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
cache.set("key", "value")
self.assertFalse(m.called)
cache.get("key", callback=m)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.get("key", "value")
@ -112,10 +112,10 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
cache.set("key", "value")
self.assertFalse(m.called)
cache.get("key", callback=m)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.get("key", callback=m)
cache.get("key", callbacks=[m])
self.assertFalse(m.called)
cache.set("key", "value2")
@ -128,7 +128,7 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
m = Mock()
cache = LruCache(1)
cache.set("key", "value", m)
cache.set("key", "value", callbacks=[m])
self.assertFalse(m.called)
cache.set("key", "value")
@ -144,7 +144,7 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
m = Mock()
cache = LruCache(1)
cache.set("key", "value", m)
cache.set("key", "value", callbacks=[m])
self.assertFalse(m.called)
cache.pop("key")
@ -163,10 +163,10 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
m4 = Mock()
cache = LruCache(4, 2, cache_type=TreeCache)
cache.set(("a", "1"), "value", m1)
cache.set(("a", "2"), "value", m2)
cache.set(("b", "1"), "value", m3)
cache.set(("b", "2"), "value", m4)
cache.set(("a", "1"), "value", callbacks=[m1])
cache.set(("a", "2"), "value", callbacks=[m2])
cache.set(("b", "1"), "value", callbacks=[m3])
cache.set(("b", "2"), "value", callbacks=[m4])
self.assertEquals(m1.call_count, 0)
self.assertEquals(m2.call_count, 0)
@ -185,8 +185,8 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
m2 = Mock()
cache = LruCache(5)
cache.set("key1", "value", m1)
cache.set("key2", "value", m2)
cache.set("key1", "value", callbacks=[m1])
cache.set("key2", "value", callbacks=[m2])
self.assertEquals(m1.call_count, 0)
self.assertEquals(m2.call_count, 0)
@ -202,14 +202,14 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
m3 = Mock(name="m3")
cache = LruCache(2)
cache.set("key1", "value", m1)
cache.set("key2", "value", m2)
cache.set("key1", "value", callbacks=[m1])
cache.set("key2", "value", callbacks=[m2])
self.assertEquals(m1.call_count, 0)
self.assertEquals(m2.call_count, 0)
self.assertEquals(m3.call_count, 0)
cache.set("key3", "value", m3)
cache.set("key3", "value", callbacks=[m3])
self.assertEquals(m1.call_count, 1)
self.assertEquals(m2.call_count, 0)
@ -227,8 +227,33 @@ class LruCacheCallbacksTestCase(unittest.TestCase):
self.assertEquals(m2.call_count, 0)
self.assertEquals(m3.call_count, 0)
cache.set("key1", "value", m1)
cache.set("key1", "value", callbacks=[m1])
self.assertEquals(m1.call_count, 1)
self.assertEquals(m2.call_count, 0)
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])