diff options
| -rw-r--r-- | changelog.d/13575.misc | 1 | ||||
| -rw-r--r-- | synapse/handlers/federation.py | 53 | ||||
| -rw-r--r-- | synapse/handlers/room.py | 14 | ||||
| -rw-r--r-- | synapse/storage/controllers/state.py | 3 | ||||
| -rw-r--r-- | synapse/storage/databases/main/roommember.py | 88 |
5 files changed, 89 insertions, 70 deletions
diff --git a/changelog.d/13575.misc b/changelog.d/13575.misc new file mode 100644 index 0000000000..3841472617 --- /dev/null +++ b/changelog.d/13575.misc @@ -0,0 +1 @@ +Optimize how Synapse calculates domains to fetch from during backfill. diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index e151962055..dd4b9f66d1 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -70,7 +70,7 @@ from synapse.replication.http.federation import ( from synapse.storage.databases.main.events import PartialStateConflictError from synapse.storage.databases.main.events_worker import EventRedactBehaviour from synapse.storage.state import StateFilter -from synapse.types import JsonDict, StateMap, get_domain_from_id +from synapse.types import JsonDict, get_domain_from_id from synapse.util.async_helpers import Linearizer from synapse.util.retryutils import NotRetryingDestination from synapse.visibility import filter_events_for_server @@ -104,37 +104,6 @@ backfill_processing_before_timer = Histogram( ) -def get_domains_from_state(state: StateMap[EventBase]) -> List[Tuple[str, int]]: - """Get joined domains from state - - Args: - state: State map from type/state key to event. - - Returns: - Returns a list of servers with the lowest depth of their joins. - Sorted by lowest depth first. - """ - joined_users = [ - (state_key, int(event.depth)) - for (e_type, state_key), event in state.items() - if e_type == EventTypes.Member and event.membership == Membership.JOIN - ] - - joined_domains: Dict[str, int] = {} - for u, d in joined_users: - try: - dom = get_domain_from_id(u) - old_d = joined_domains.get(dom) - if old_d: - joined_domains[dom] = min(d, old_d) - else: - joined_domains[dom] = d - except Exception: - pass - - return sorted(joined_domains.items(), key=lambda d: d[1]) - - class _BackfillPointType(Enum): # a regular backwards extremity (ie, an event which we don't yet have, but which # is referred to by other events in the DAG) @@ -432,21 +401,19 @@ class FederationHandler: ) # Now we need to decide which hosts to hit first. - - # First we try hosts that are already in the room + # First we try hosts that are already in the room. # TODO: HEURISTIC ALERT. + likely_domains = ( + await self._storage_controllers.state.get_current_hosts_in_room(room_id) + ) - curr_state = await self._storage_controllers.state.get_current_state(room_id) - - curr_domains = get_domains_from_state(curr_state) - - likely_domains = [ - domain for domain, depth in curr_domains if domain != self.server_name - ] - - async def try_backfill(domains: List[str]) -> bool: + async def try_backfill(domains: Collection[str]) -> bool: # TODO: Should we try multiple of these at a time? for dom in domains: + # We don't want to ask our own server for information we don't have + if dom == self.server_name: + continue + try: await self._federation_event_handler.backfill( dom, room_id, limit=100, extremities=extremities_to_request diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py index 2fc8264858..f64a8690a5 100644 --- a/synapse/handlers/room.py +++ b/synapse/handlers/room.py @@ -60,7 +60,6 @@ from synapse.event_auth import validate_event_for_room_version from synapse.events import EventBase from synapse.events.utils import copy_and_fixup_power_levels_contents from synapse.federation.federation_client import InvalidResponseError -from synapse.handlers.federation import get_domains_from_state from synapse.handlers.relations import BundledAggregations from synapse.module_api import NOT_SPAM from synapse.rest.admin._base import assert_user_is_admin @@ -1462,17 +1461,16 @@ class TimestampLookupHandler: timestamp, ) - # Find other homeservers from the given state in the room - curr_state = await self._storage_controllers.state.get_current_state( - room_id + likely_domains = ( + await self._storage_controllers.state.get_current_hosts_in_room(room_id) ) - curr_domains = get_domains_from_state(curr_state) - likely_domains = [ - domain for domain, depth in curr_domains if domain != self.server_name - ] # Loop through each homeserver candidate until we get a succesful response for domain in likely_domains: + # We don't want to ask our own server for information we don't have + if domain == self.server_name: + continue + try: remote_response = await self.federation_client.timestamp_to_event( domain, room_id, timestamp, direction diff --git a/synapse/storage/controllers/state.py b/synapse/storage/controllers/state.py index f9ffd0e29e..ba5380ce3e 100644 --- a/synapse/storage/controllers/state.py +++ b/synapse/storage/controllers/state.py @@ -23,7 +23,6 @@ from typing import ( List, Mapping, Optional, - Set, Tuple, ) @@ -520,7 +519,7 @@ class StateStorageController: ) return state_map.get(key) - async def get_current_hosts_in_room(self, room_id: str) -> Set[str]: + async def get_current_hosts_in_room(self, room_id: str) -> List[str]: """Get current hosts in room based on current state.""" await self._partial_state_room_tracker.await_full_state(room_id) diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py index 9e5034b401..06500457bd 100644 --- a/synapse/storage/databases/main/roommember.py +++ b/synapse/storage/databases/main/roommember.py @@ -187,27 +187,48 @@ class RoomMemberWorkerStore(EventsWorkerStore): @cached(max_entries=100000, iterable=True) async def get_users_in_room(self, room_id: str) -> List[str]: + """ + Returns a list of users in the room sorted by longest in the room first + (aka. with the lowest depth). This is done to match the sort in + `get_current_hosts_in_room()` and so we can re-use the cache but it's + not horrible to have here either. + """ + return await self.db_pool.runInteraction( "get_users_in_room", self.get_users_in_room_txn, room_id ) def get_users_in_room_txn(self, txn: LoggingTransaction, room_id: str) -> List[str]: + """ + Returns a list of users in the room sorted by longest in the room first + (aka. with the lowest depth). This is done to match the sort in + `get_current_hosts_in_room()` and so we can re-use the cache but it's + not horrible to have here either. + """ # If we can assume current_state_events.membership is up to date # then we can avoid a join, which is a Very Good Thing given how # frequently this function gets called. if self._current_state_events_membership_up_to_date: sql = """ - SELECT state_key FROM current_state_events - WHERE type = 'm.room.member' AND room_id = ? AND membership = ? + SELECT c.state_key FROM current_state_events as c + /* Get the depth of the event from the events table */ + INNER JOIN events AS e USING (event_id) + WHERE c.type = 'm.room.member' AND c.room_id = ? AND membership = ? + /* Sorted by lowest depth first */ + ORDER BY e.depth ASC; """ else: sql = """ - SELECT state_key FROM room_memberships as m + SELECT c.state_key FROM room_memberships as m + /* Get the depth of the event from the events table */ + INNER JOIN events AS e USING (event_id) INNER JOIN current_state_events as c ON m.event_id = c.event_id AND m.room_id = c.room_id AND m.user_id = c.state_key WHERE c.type = 'm.room.member' AND c.room_id = ? AND m.membership = ? + /* Sorted by lowest depth first */ + ORDER BY e.depth ASC; """ txn.execute(sql, (room_id, Membership.JOIN)) @@ -1037,37 +1058,70 @@ class RoomMemberWorkerStore(EventsWorkerStore): return True @cached(iterable=True, max_entries=10000) - async def get_current_hosts_in_room(self, room_id: str) -> Set[str]: - """Get current hosts in room based on current state.""" + async def get_current_hosts_in_room(self, room_id: str) -> List[str]: + """ + Get current hosts in room based on current state. + + The heuristic of sorting by servers who have been in the room the + longest is good because they're most likely to have anything we ask + about. + + Returns: + Returns a list of servers sorted by longest in the room first. (aka. + sorted by join with the lowest depth first). + """ # First we check if we already have `get_users_in_room` in the cache, as # we can just calculate result from that users = self.get_users_in_room.cache.get_immediate( (room_id,), None, update_metrics=False ) - if users is not None: - return {get_domain_from_id(u) for u in users} - - if isinstance(self.database_engine, Sqlite3Engine): + if users is None and isinstance(self.database_engine, Sqlite3Engine): # If we're using SQLite then let's just always use # `get_users_in_room` rather than funky SQL. users = await self.get_users_in_room(room_id) - return {get_domain_from_id(u) for u in users} + + if users is not None: + # Because `users` is sorted from lowest -> highest depth, the list + # of domains will also be sorted that way. + domains: List[str] = [] + # We use a `Set` just for fast lookups + domain_set: Set[str] = set() + for u in users: + domain = get_domain_from_id(u) + if domain not in domain_set: + domain_set.add(domain) + domains.append(domain) + return domains # For PostgreSQL we can use a regex to pull out the domains from the # joined users in `current_state_events` via regex. - def get_current_hosts_in_room_txn(txn: LoggingTransaction) -> Set[str]: + def get_current_hosts_in_room_txn(txn: LoggingTransaction) -> List[str]: + # Returns a list of servers currently joined in the room sorted by + # longest in the room first (aka. with the lowest depth). The + # heuristic of sorting by servers who have been in the room the + # longest is good because they're most likely to have anything we + # ask about. sql = """ - SELECT DISTINCT substring(state_key FROM '@[^:]*:(.*)$') - FROM current_state_events + SELECT + /* Match the domain part of the MXID */ + substring(c.state_key FROM '@[^:]*:(.*)$') as server_domain + FROM current_state_events c + /* Get the depth of the event from the events table */ + INNER JOIN events AS e USING (event_id) WHERE - type = 'm.room.member' - AND membership = 'join' - AND room_id = ? + /* Find any join state events in the room */ + c.type = 'm.room.member' + AND c.membership = 'join' + AND c.room_id = ? + /* Group all state events from the same domain into their own buckets (groups) */ + GROUP BY server_domain + /* Sorted by lowest depth first */ + ORDER BY min(e.depth) ASC; """ txn.execute(sql, (room_id,)) - return {d for d, in txn} + return [d for d, in txn] return await self.db_pool.runInteraction( "get_current_hosts_in_room", get_current_hosts_in_room_txn |