diff options
| -rw-r--r-- | changelog.d/9845.misc | 1 | ||||
| -rw-r--r-- | synapse/push/bulk_push_rule_evaluator.py | 161 | ||||
| -rw-r--r-- | synapse/storage/databases/main/roommember.py | 161 |
3 files changed, 182 insertions, 141 deletions
diff --git a/changelog.d/9845.misc b/changelog.d/9845.misc new file mode 100644 index 0000000000..875dd6d131 --- /dev/null +++ b/changelog.d/9845.misc @@ -0,0 +1 @@ +Only store the raw data in the in-memory caches, rather than objects that include references to e.g. the data stores. diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py index 50b470c310..350646f458 100644 --- a/synapse/push/bulk_push_rule_evaluator.py +++ b/synapse/push/bulk_push_rule_evaluator.py @@ -106,6 +106,10 @@ class BulkPushRuleEvaluator: self.store = hs.get_datastore() self.auth = hs.get_auth() + # Used by `RulesForRoom` to ensure only one thing mutates the cache at a + # time. Keyed off room_id. + self._rules_linearizer = Linearizer(name="rules_for_room") + self.room_push_rule_cache_metrics = register_cache( "cache", "room_push_rule_cache", @@ -123,7 +127,16 @@ class BulkPushRuleEvaluator: dict of user_id -> push_rules """ room_id = event.room_id - rules_for_room = self._get_rules_for_room(room_id) + + rules_for_room_data = self._get_rules_for_room(room_id) + rules_for_room = RulesForRoom( + hs=self.hs, + room_id=room_id, + rules_for_room_cache=self._get_rules_for_room.cache, + room_push_rule_cache_metrics=self.room_push_rule_cache_metrics, + linearizer=self._rules_linearizer, + cached_data=rules_for_room_data, + ) rules_by_user = await rules_for_room.get_rules(event, context) @@ -142,17 +155,12 @@ class BulkPushRuleEvaluator: return rules_by_user @lru_cache() - def _get_rules_for_room(self, room_id: str) -> "RulesForRoom": - """Get the current RulesForRoom object for the given room id""" - # It's important that RulesForRoom gets added to self._get_rules_for_room.cache + def _get_rules_for_room(self, room_id: str) -> "RulesForRoomData": + """Get the current RulesForRoomData object for the given room id""" + # It's important that the RulesForRoomData object gets added to self._get_rules_for_room.cache # before any lookup methods get called on it as otherwise there may be # a race if invalidate_all gets called (which assumes its in the cache) - return RulesForRoom( - self.hs, - room_id, - self._get_rules_for_room.cache, - self.room_push_rule_cache_metrics, - ) + return RulesForRoomData() async def _get_power_levels_and_sender_level( self, event: EventBase, context: EventContext @@ -282,11 +290,49 @@ def _condition_checker( return True +@attr.s(slots=True) +class RulesForRoomData: + """The data stored in the cache by `RulesForRoom`. + + We don't store `RulesForRoom` directly in the cache as we want our caches to + *only* include data, and not references to e.g. the data stores. + """ + + # event_id -> (user_id, state) + member_map = attr.ib(type=Dict[str, Tuple[str, str]], factory=dict) + # user_id -> rules + rules_by_user = attr.ib(type=Dict[str, List[Dict[str, dict]]], factory=dict) + + # The last state group we updated the caches for. If the state_group of + # a new event comes along, we know that we can just return the cached + # result. + # On invalidation of the rules themselves (if the user changes them), + # we invalidate everything and set state_group to `object()` + state_group = attr.ib(type=Union[object, int], factory=object) + + # A sequence number to keep track of when we're allowed to update the + # cache. We bump the sequence number when we invalidate the cache. If + # the sequence number changes while we're calculating stuff we should + # not update the cache with it. + sequence = attr.ib(type=int, default=0) + + # A cache of user_ids that we *know* aren't interesting, e.g. user_ids + # owned by AS's, or remote users, etc. (I.e. users we will never need to + # calculate push for) + # These never need to be invalidated as we will never set up push for + # them. + uninteresting_user_set = attr.ib(type=Set[str], factory=set) + + class RulesForRoom: """Caches push rules for users in a room. This efficiently handles users joining/leaving the room by not invalidating the entire cache for the room. + + A new instance is constructed for each call to + `BulkPushRuleEvaluator._get_rules_for_event`, with the cached data from + previous calls passed in. """ def __init__( @@ -295,6 +341,8 @@ class RulesForRoom: room_id: str, rules_for_room_cache: LruCache, room_push_rule_cache_metrics: CacheMetric, + linearizer: Linearizer, + cached_data: RulesForRoomData, ): """ Args: @@ -303,38 +351,21 @@ class RulesForRoom: rules_for_room_cache: The cache object that caches these RoomsForUser objects. room_push_rule_cache_metrics: The metrics object + linearizer: The linearizer used to ensure only one thing mutates + the cache at a time. Keyed off room_id + cached_data: Cached data from previous calls to `self.get_rules`, + can be mutated. """ self.room_id = room_id self.is_mine_id = hs.is_mine_id self.store = hs.get_datastore() self.room_push_rule_cache_metrics = room_push_rule_cache_metrics - self.linearizer = Linearizer(name="rules_for_room") - - # event_id -> (user_id, state) - self.member_map = {} # type: Dict[str, Tuple[str, str]] - # user_id -> rules - self.rules_by_user = {} # type: Dict[str, List[Dict[str, dict]]] - - # The last state group we updated the caches for. If the state_group of - # a new event comes along, we know that we can just return the cached - # result. - # On invalidation of the rules themselves (if the user changes them), - # we invalidate everything and set state_group to `object()` - self.state_group = object() - - # A sequence number to keep track of when we're allowed to update the - # cache. We bump the sequence number when we invalidate the cache. If - # the sequence number changes while we're calculating stuff we should - # not update the cache with it. - self.sequence = 0 - - # A cache of user_ids that we *know* aren't interesting, e.g. user_ids - # owned by AS's, or remote users, etc. (I.e. users we will never need to - # calculate push for) - # These never need to be invalidated as we will never set up push for - # them. - self.uninteresting_user_set = set() # type: Set[str] + # Used to ensure only one thing mutates the cache at a time. Keyed off + # room_id. + self.linearizer = linearizer + + self.data = cached_data # We need to be clever on the invalidating caches callbacks, as # otherwise the invalidation callback holds a reference to the object, @@ -352,25 +383,25 @@ class RulesForRoom: """ state_group = context.state_group - if state_group and self.state_group == state_group: + if state_group and self.data.state_group == state_group: logger.debug("Using cached rules for %r", self.room_id) self.room_push_rule_cache_metrics.inc_hits() - return self.rules_by_user + return self.data.rules_by_user - with (await self.linearizer.queue(())): - if state_group and self.state_group == state_group: + with (await self.linearizer.queue(self.room_id)): + if state_group and self.data.state_group == state_group: logger.debug("Using cached rules for %r", self.room_id) self.room_push_rule_cache_metrics.inc_hits() - return self.rules_by_user + return self.data.rules_by_user self.room_push_rule_cache_metrics.inc_misses() ret_rules_by_user = {} missing_member_event_ids = {} - if state_group and self.state_group == context.prev_group: + if state_group and self.data.state_group == context.prev_group: # If we have a simple delta then we can reuse most of the previous # results. - ret_rules_by_user = self.rules_by_user + ret_rules_by_user = self.data.rules_by_user current_state_ids = context.delta_ids push_rules_delta_state_cache_metric.inc_hits() @@ -393,24 +424,24 @@ class RulesForRoom: if typ != EventTypes.Member: continue - if user_id in self.uninteresting_user_set: + if user_id in self.data.uninteresting_user_set: continue if not self.is_mine_id(user_id): - self.uninteresting_user_set.add(user_id) + self.data.uninteresting_user_set.add(user_id) continue if self.store.get_if_app_services_interested_in_user(user_id): - self.uninteresting_user_set.add(user_id) + self.data.uninteresting_user_set.add(user_id) continue event_id = current_state_ids[key] - res = self.member_map.get(event_id, None) + res = self.data.member_map.get(event_id, None) if res: user_id, state = res if state == Membership.JOIN: - rules = self.rules_by_user.get(user_id, None) + rules = self.data.rules_by_user.get(user_id, None) if rules: ret_rules_by_user[user_id] = rules continue @@ -430,7 +461,7 @@ class RulesForRoom: else: # The push rules didn't change but lets update the cache anyway self.update_cache( - self.sequence, + self.data.sequence, members={}, # There were no membership changes rules_by_user=ret_rules_by_user, state_group=state_group, @@ -461,7 +492,7 @@ class RulesForRoom: for. Used when updating the cache. event: The event we are currently computing push rules for. """ - sequence = self.sequence + sequence = self.data.sequence rows = await self.store.get_membership_from_event_ids(member_event_ids.values()) @@ -501,23 +532,11 @@ class RulesForRoom: self.update_cache(sequence, members, ret_rules_by_user, state_group) - def invalidate_all(self) -> None: - # Note: Don't hand this function directly to an invalidation callback - # as it keeps a reference to self and will stop this instance from being - # GC'd if it gets dropped from the rules_to_user cache. Instead use - # `self.invalidate_all_cb` - logger.debug("Invalidating RulesForRoom for %r", self.room_id) - self.sequence += 1 - self.state_group = object() - self.member_map = {} - self.rules_by_user = {} - push_rules_invalidation_counter.inc() - def update_cache(self, sequence, members, rules_by_user, state_group) -> None: - if sequence == self.sequence: - self.member_map.update(members) - self.rules_by_user = rules_by_user - self.state_group = state_group + if sequence == self.data.sequence: + self.data.member_map.update(members) + self.data.rules_by_user = rules_by_user + self.data.state_group = state_group @attr.attrs(slots=True, frozen=True) @@ -535,6 +554,10 @@ class _Invalidation: room_id = attr.ib(type=str) def __call__(self) -> None: - rules = self.cache.get(self.room_id, None, update_metrics=False) - if rules: - rules.invalidate_all() + rules_data = self.cache.get(self.room_id, None, update_metrics=False) + if rules_data: + rules_data.sequence += 1 + rules_data.state_group = object() + rules_data.member_map = {} + rules_data.rules_by_user = {} + push_rules_invalidation_counter.inc() diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py index bd8513cd43..2a8532f8c1 100644 --- a/synapse/storage/databases/main/roommember.py +++ b/synapse/storage/databases/main/roommember.py @@ -23,8 +23,11 @@ from typing import ( Optional, Set, Tuple, + Union, ) +import attr + from synapse.api.constants import EventTypes, Membership from synapse.events import EventBase from synapse.events.snapshot import EventContext @@ -43,7 +46,7 @@ from synapse.storage.roommember import ( ProfileInfo, RoomsForUser, ) -from synapse.types import PersistedEventPosition, get_domain_from_id +from synapse.types import PersistedEventPosition, StateMap, get_domain_from_id from synapse.util.async_helpers import Linearizer from synapse.util.caches import intern_string from synapse.util.caches.descriptors import _CacheContext, cached, cachedList @@ -63,6 +66,10 @@ class RoomMemberWorkerStore(EventsWorkerStore): def __init__(self, database: DatabasePool, db_conn, hs): super().__init__(database, db_conn, hs) + # Used by `_get_joined_hosts` to ensure only one thing mutates the cache + # at a time. Keyed by room_id. + self._joined_host_linearizer = Linearizer("_JoinedHostsCache") + # Is the current_state_events.membership up to date? Or is the # background update still running? self._current_state_events_membership_up_to_date = False @@ -740,19 +747,82 @@ class RoomMemberWorkerStore(EventsWorkerStore): @cached(num_args=2, max_entries=10000, iterable=True) async def _get_joined_hosts( - self, room_id, state_group, current_state_ids, state_entry - ): - # We don't use `state_group`, its there so that we can cache based - # on it. However, its important that its never None, since two current_state's - # with a state_group of None are likely to be different. + self, + room_id: str, + state_group: int, + current_state_ids: StateMap[str], + state_entry: "_StateCacheEntry", + ) -> FrozenSet[str]: + # We don't use `state_group`, its there so that we can cache based on + # it. However, its important that its never None, since two + # current_state's with a state_group of None are likely to be different. + # + # The `state_group` must match the `state_entry.state_group` (if not None). assert state_group is not None - + assert state_entry.state_group is None or state_entry.state_group == state_group + + # We use a secondary cache of previous work to allow us to build up the + # joined hosts for the given state group based on previous state groups. + # + # We cache one object per room containing the results of the last state + # group we got joined hosts for. The idea is that generally + # `get_joined_hosts` is called with the "current" state group for the + # room, and so consecutive calls will be for consecutive state groups + # which point to the previous state group. cache = await self._get_joined_hosts_cache(room_id) - return await cache.get_destinations(state_entry) + + # If the state group in the cache matches, we already have the data we need. + if state_entry.state_group == cache.state_group: + return frozenset(cache.hosts_to_joined_users) + + # Since we'll mutate the cache we need to lock. + with (await self._joined_host_linearizer.queue(room_id)): + if state_entry.state_group == cache.state_group: + # Same state group, so nothing to do. We've already checked for + # this above, but the cache may have changed while waiting on + # the lock. + pass + elif state_entry.prev_group == cache.state_group: + # The cached work is for the previous state group, so we work out + # the delta. + for (typ, state_key), event_id in state_entry.delta_ids.items(): + if typ != EventTypes.Member: + continue + + host = intern_string(get_domain_from_id(state_key)) + user_id = state_key + known_joins = cache.hosts_to_joined_users.setdefault(host, set()) + + event = await self.get_event(event_id) + if event.membership == Membership.JOIN: + known_joins.add(user_id) + else: + known_joins.discard(user_id) + + if not known_joins: + cache.hosts_to_joined_users.pop(host, None) + else: + # The cache doesn't match the state group or prev state group, + # so we calculate the result from first principles. + joined_users = await self.get_joined_users_from_state( + room_id, state_entry + ) + + cache.hosts_to_joined_users = {} + for user_id in joined_users: + host = intern_string(get_domain_from_id(user_id)) + cache.hosts_to_joined_users.setdefault(host, set()).add(user_id) + + if state_entry.state_group: + cache.state_group = state_entry.state_group + else: + cache.state_group = object() + + return frozenset(cache.hosts_to_joined_users) @cached(max_entries=10000) def _get_joined_hosts_cache(self, room_id: str) -> "_JoinedHostsCache": - return _JoinedHostsCache(self, room_id) + return _JoinedHostsCache() @cached(num_args=2) async def did_forget(self, user_id: str, room_id: str) -> bool: @@ -1062,71 +1132,18 @@ class RoomMemberStore(RoomMemberWorkerStore, RoomMemberBackgroundUpdateStore): await self.db_pool.runInteraction("forget_membership", f) +@attr.s(slots=True) class _JoinedHostsCache: - """Cache for joined hosts in a room that is optimised to handle updates - via state deltas. - """ - - def __init__(self, store, room_id): - self.store = store - self.room_id = room_id + """The cached data used by the `_get_joined_hosts_cache`.""" - self.hosts_to_joined_users = {} + # Dict of host to the set of their users in the room at the state group. + hosts_to_joined_users = attr.ib(type=Dict[str, Set[str]], factory=dict) - self.state_group = object() - - self.linearizer = Linearizer("_JoinedHostsCache") - - self._len = 0 - - async def get_destinations(self, state_entry: "_StateCacheEntry") -> Set[str]: - """Get set of destinations for a state entry - - Args: - state_entry - - Returns: - The destinations as a set. - """ - if state_entry.state_group == self.state_group: - return frozenset(self.hosts_to_joined_users) - - with (await self.linearizer.queue(())): - if state_entry.state_group == self.state_group: - pass - elif state_entry.prev_group == self.state_group: - for (typ, state_key), event_id in state_entry.delta_ids.items(): - if typ != EventTypes.Member: - continue - - host = intern_string(get_domain_from_id(state_key)) - user_id = state_key - known_joins = self.hosts_to_joined_users.setdefault(host, set()) - - event = await self.store.get_event(event_id) - if event.membership == Membership.JOIN: - known_joins.add(user_id) - else: - known_joins.discard(user_id) - - if not known_joins: - self.hosts_to_joined_users.pop(host, None) - else: - joined_users = await self.store.get_joined_users_from_state( - self.room_id, state_entry - ) - - self.hosts_to_joined_users = {} - for user_id in joined_users: - host = intern_string(get_domain_from_id(user_id)) - self.hosts_to_joined_users.setdefault(host, set()).add(user_id) - - if state_entry.state_group: - self.state_group = state_entry.state_group - else: - self.state_group = object() - self._len = sum(len(v) for v in self.hosts_to_joined_users.values()) - return frozenset(self.hosts_to_joined_users) + # The state group `hosts_to_joined_users` is derived from. Will be an object + # if the instance is newly created or if the state is not based on a state + # group. (An object is used as a sentinel value to ensure that it never is + # equal to anything else). + state_group = attr.ib(type=Union[object, int], factory=object) def __len__(self): - return self._len + return sum(len(v) for v in self.hosts_to_joined_users.values()) |