Add a five minute cache to get_destination_retry_timings

Hopefully helps with #3931
This commit is contained in:
Erik Johnston 2018-09-21 14:55:47 +01:00
parent 79eded1ae4
commit fdd1a62e8d
2 changed files with 35 additions and 1 deletions

View file

@ -23,6 +23,7 @@ from canonicaljson import encode_canonical_json
from twisted.internet import defer
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.util.caches.expiringcache import ExpiringCache
from ._base import SQLBaseStore, db_to_json
@ -49,6 +50,8 @@ _UpdateTransactionRow = namedtuple(
)
)
SENTINEL = object()
class TransactionStore(SQLBaseStore):
"""A collection of queries for handling PDUs.
@ -59,6 +62,12 @@ class TransactionStore(SQLBaseStore):
self._clock.looping_call(self._start_cleanup_transactions, 30 * 60 * 1000)
self._destination_retry_cache = ExpiringCache(
cache_name="get_destination_retry_timings",
clock=self._clock,
expiry_ms=5 * 60 * 1000,
)
def get_received_txn_response(self, transaction_id, origin):
"""For an incoming transaction from a given origin, check if we have
already responded to it. If so, return the response code and response
@ -155,6 +164,7 @@ class TransactionStore(SQLBaseStore):
"""
pass
@defer.inlineCallbacks
def get_destination_retry_timings(self, destination):
"""Gets the current retry timings (if any) for a given destination.
@ -165,10 +175,20 @@ class TransactionStore(SQLBaseStore):
None if not retrying
Otherwise a dict for the retry scheme
"""
return self.runInteraction(
result = self._destination_retry_cache.get(destination, SENTINEL)
if result is not SENTINEL:
defer.returnValue(result)
result = yield self.runInteraction(
"get_destination_retry_timings",
self._get_destination_retry_timings, destination)
# We don't hugely care about race conditions between getting and
# invalidating the cache, since we time out fairly quickly anyway.
self._destination_retry_cache[destination] = result
defer.returnValue(result)
def _get_destination_retry_timings(self, txn, destination):
result = self._simple_select_one_txn(
txn,
@ -196,6 +216,7 @@ class TransactionStore(SQLBaseStore):
retry_interval (int) - how long until next retry in ms
"""
self._destination_retry_cache.pop(destination)
return self.runInteraction(
"set_destination_retry_timings",
self._set_destination_retry_timings,

View file

@ -24,6 +24,9 @@ from synapse.util.caches import register_cache
logger = logging.getLogger(__name__)
SENTINEL = object()
class ExpiringCache(object):
def __init__(self, cache_name, clock, max_len=0, expiry_ms=0,
reset_expiry_on_get=False, iterable=False):
@ -102,6 +105,16 @@ class ExpiringCache(object):
return entry.value
def pop(self, key, default=None):
value = self._cache.pop(key, SENTINEL)
if value is SENTINEL:
return default
if self.iterable:
self._size_estimate -= len(value.value)
return value
def __contains__(self, key):
return key in self._cache