Add support for 'iterable' to ExpiringCache

This commit is contained in:
Erik Johnston 2017-01-16 13:48:04 +00:00
parent 01521299c7
commit 46aebbbcbf
2 changed files with 22 additions and 10 deletions

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(10000 * 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,
)

View File

@ -23,7 +23,7 @@ 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 +36,8 @@ 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
@ -49,7 +51,9 @@ class ExpiringCache(object):
self._cache = {}
self.metrics = register_cache(cache_name, self._cache)
self.metrics = register_cache(cache_name, self)
self.iterable = iterable
def start(self):
if not self._expiry_ms:
@ -66,14 +70,15 @@ class ExpiringCache(object):
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:
if self._max_len and len(self) > self._max_len:
sorted_entries = sorted(
self._cache.items(),
self._cache.keys(),
key=lambda item: item[1].time,
)
for k, _ in sorted_entries[self._max_len:]:
self._cache.pop(k)
while len(self) > self._max_len and sorted_entries:
key = sorted_entries.pop()
self._cache.pop(key)
def __getitem__(self, key):
try:
@ -99,7 +104,7 @@ 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()
@ -114,11 +119,14 @@ class ExpiringCache(object):
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):
return len(self._cache)
if self.iterable:
return sum(len(value.value) for value in self._cache.itervalues())
else:
return len(self._cache)
class _CacheEntry(object):