From 49c9745b4516dec8728c260f1a6784f2c510110c Mon Sep 17 00:00:00 2001 From: Patrick Cloke Date: Wed, 18 Oct 2023 12:26:01 -0400 Subject: Avoid sending massive replication updates when purging a room. (#16510) --- changelog.d/16510.misc | 1 + synapse/replication/tcp/streams/events.py | 45 +++++++++++++- synapse/storage/databases/main/cache.py | 8 +++ tests/replication/tcp/streams/test_events.py | 91 +++++++++++++++++++--------- 4 files changed, 115 insertions(+), 30 deletions(-) create mode 100644 changelog.d/16510.misc diff --git a/changelog.d/16510.misc b/changelog.d/16510.misc new file mode 100644 index 0000000000..5556b5d74c --- /dev/null +++ b/changelog.d/16510.misc @@ -0,0 +1 @@ +Improve replication performance when purging rooms. diff --git a/synapse/replication/tcp/streams/events.py b/synapse/replication/tcp/streams/events.py index ad9b760713..da6d948e1b 100644 --- a/synapse/replication/tcp/streams/events.py +++ b/synapse/replication/tcp/streams/events.py @@ -13,6 +13,7 @@ # See the License for the specific language governing permissions and # limitations under the License. import heapq +from collections import defaultdict from typing import TYPE_CHECKING, Iterable, Optional, Tuple, Type, TypeVar, cast import attr @@ -51,8 +52,19 @@ data part are: * The state_key of the state which has changed * The event id of the new state +A "state-all" row is sent whenever the "current state" in a room changes, but there are +too many state updates for a particular room in the same update. This replaces any +"state" rows on a per-room basis. The fields in the data part are: + +* The room id for the state changes + """ +# Any room with more than _MAX_STATE_UPDATES_PER_ROOM will send a EventsStreamAllStateRow +# instead of individual EventsStreamEventRow. This is predominantly useful when +# purging large rooms. +_MAX_STATE_UPDATES_PER_ROOM = 150 + @attr.s(slots=True, frozen=True, auto_attribs=True) class EventsStreamRow: @@ -111,9 +123,17 @@ class EventsStreamCurrentStateRow(BaseEventsStreamRow): event_id: Optional[str] +@attr.s(slots=True, frozen=True, auto_attribs=True) +class EventsStreamAllStateRow(BaseEventsStreamRow): + TypeId = "state-all" + + room_id: str + + _EventRows: Tuple[Type[BaseEventsStreamRow], ...] = ( EventsStreamEventRow, EventsStreamCurrentStateRow, + EventsStreamAllStateRow, ) TypeToRow = {Row.TypeId: Row for Row in _EventRows} @@ -213,9 +233,28 @@ class EventsStream(Stream): if stream_id <= upper_limit ) + # Separate out rooms that have many state updates, listeners should clear + # all state for those rooms. + state_updates_by_room = defaultdict(list) + for stream_id, room_id, _type, _state_key, _event_id in state_rows: + state_updates_by_room[room_id].append(stream_id) + + state_all_rows = [ + (stream_ids[-1], room_id) + for room_id, stream_ids in state_updates_by_room.items() + if len(stream_ids) >= _MAX_STATE_UPDATES_PER_ROOM + ] + state_all_updates: Iterable[Tuple[int, Tuple]] = ( + (max_stream_id, (EventsStreamAllStateRow.TypeId, (room_id,))) + for (max_stream_id, room_id) in state_all_rows + ) + + # Any remaining state updates are sent individually. + state_all_rooms = {room_id for _, room_id in state_all_rows} state_updates: Iterable[Tuple[int, Tuple]] = ( (stream_id, (EventsStreamCurrentStateRow.TypeId, rest)) for (stream_id, *rest) in state_rows + if rest[0] not in state_all_rooms ) ex_outliers_updates: Iterable[Tuple[int, Tuple]] = ( @@ -224,7 +263,11 @@ class EventsStream(Stream): ) # we need to return a sorted list, so merge them together. - updates = list(heapq.merge(event_updates, state_updates, ex_outliers_updates)) + updates = list( + heapq.merge( + event_updates, state_all_updates, state_updates, ex_outliers_updates + ) + ) return updates, upper_limit, limited @classmethod diff --git a/synapse/storage/databases/main/cache.py b/synapse/storage/databases/main/cache.py index 2fbd389c71..4d0470ffd9 100644 --- a/synapse/storage/databases/main/cache.py +++ b/synapse/storage/databases/main/cache.py @@ -23,6 +23,7 @@ from synapse.metrics.background_process_metrics import wrap_as_background_proces from synapse.replication.tcp.streams import BackfillStream, CachesStream from synapse.replication.tcp.streams.events import ( EventsStream, + EventsStreamAllStateRow, EventsStreamCurrentStateRow, EventsStreamEventRow, EventsStreamRow, @@ -264,6 +265,13 @@ class CacheInvalidationWorkerStore(SQLBaseStore): (data.state_key,) ) self.get_rooms_for_user.invalidate((data.state_key,)) # type: ignore[attr-defined] + elif row.type == EventsStreamAllStateRow.TypeId: + assert isinstance(data, EventsStreamAllStateRow) + # Similar to the above, but the entire caches are invalidated. This is + # unfortunate for the membership caches, but should recover quickly. + self._curr_state_delta_stream_cache.entity_has_changed(data.room_id, token) # type: ignore[attr-defined] + self.get_rooms_for_user_with_stream_ordering.invalidate_all() # type: ignore[attr-defined] + self.get_rooms_for_user.invalidate_all() # type: ignore[attr-defined] else: raise Exception("Unknown events stream row type %s" % (row.type,)) diff --git a/tests/replication/tcp/streams/test_events.py b/tests/replication/tcp/streams/test_events.py index 128fc3e046..b8ab4ee54b 100644 --- a/tests/replication/tcp/streams/test_events.py +++ b/tests/replication/tcp/streams/test_events.py @@ -14,6 +14,8 @@ from typing import Any, List, Optional +from parameterized import parameterized + from twisted.test.proto_helpers import MemoryReactor from synapse.api.constants import EventTypes, Membership @@ -21,6 +23,8 @@ from synapse.events import EventBase from synapse.replication.tcp.commands import RdataCommand from synapse.replication.tcp.streams._base import _STREAM_UPDATE_TARGET_ROW_COUNT from synapse.replication.tcp.streams.events import ( + _MAX_STATE_UPDATES_PER_ROOM, + EventsStreamAllStateRow, EventsStreamCurrentStateRow, EventsStreamEventRow, EventsStreamRow, @@ -106,11 +110,21 @@ class EventsStreamTestCase(BaseStreamTestCase): self.assertEqual([], received_rows) - def test_update_function_huge_state_change(self) -> None: + @parameterized.expand( + [(_STREAM_UPDATE_TARGET_ROW_COUNT, False), (_MAX_STATE_UPDATES_PER_ROOM, True)] + ) + def test_update_function_huge_state_change( + self, num_state_changes: int, collapse_state_changes: bool + ) -> None: """Test replication with many state events Ensures that all events are correctly replicated when there are lots of state change rows to be replicated. + + Args: + num_state_changes: The number of state changes to create. + collapse_state_changes: Whether the state changes are expected to be + collapsed or not. """ # we want to generate lots of state changes at a single stream ID. @@ -145,7 +159,7 @@ class EventsStreamTestCase(BaseStreamTestCase): events = [ self._inject_state_event(sender=OTHER_USER) - for _ in range(_STREAM_UPDATE_TARGET_ROW_COUNT) + for _ in range(num_state_changes) ] self.replicate() @@ -202,8 +216,7 @@ class EventsStreamTestCase(BaseStreamTestCase): row for row in self.test_handler.received_rdata_rows if row[0] == "events" ] - # first check the first two rows, which should be state1 - + # first check the first two rows, which should be the state1 event. stream_name, token, row = received_rows.pop(0) self.assertEqual("events", stream_name) self.assertIsInstance(row, EventsStreamRow) @@ -217,7 +230,7 @@ class EventsStreamTestCase(BaseStreamTestCase): self.assertIsInstance(row.data, EventsStreamCurrentStateRow) self.assertEqual(row.data.event_id, state1.event_id) - # now the last two rows, which should be state2 + # now the last two rows, which should be the state2 event. stream_name, token, row = received_rows.pop(-2) self.assertEqual("events", stream_name) self.assertIsInstance(row, EventsStreamRow) @@ -231,34 +244,54 @@ class EventsStreamTestCase(BaseStreamTestCase): self.assertIsInstance(row.data, EventsStreamCurrentStateRow) self.assertEqual(row.data.event_id, state2.event_id) - # that should leave us with the rows for the PL event - self.assertEqual(len(received_rows), len(events) + 2) + # Based on the number of + if collapse_state_changes: + # that should leave us with the rows for the PL event, the state changes + # get collapsed into a single row. + self.assertEqual(len(received_rows), 2) - stream_name, token, row = received_rows.pop(0) - self.assertEqual("events", stream_name) - self.assertIsInstance(row, EventsStreamRow) - self.assertEqual(row.type, "ev") - self.assertIsInstance(row.data, EventsStreamEventRow) - self.assertEqual(row.data.event_id, pl_event.event_id) + stream_name, token, row = received_rows.pop(0) + self.assertEqual("events", stream_name) + self.assertIsInstance(row, EventsStreamRow) + self.assertEqual(row.type, "ev") + self.assertIsInstance(row.data, EventsStreamEventRow) + self.assertEqual(row.data.event_id, pl_event.event_id) - # the state rows are unsorted - state_rows: List[EventsStreamCurrentStateRow] = [] - for stream_name, _, row in received_rows: + stream_name, token, row = received_rows.pop(0) + self.assertIsInstance(row, EventsStreamRow) + self.assertEqual(row.type, "state-all") + self.assertIsInstance(row.data, EventsStreamAllStateRow) + self.assertEqual(row.data.room_id, state2.room_id) + + else: + # that should leave us with the rows for the PL event + self.assertEqual(len(received_rows), len(events) + 2) + + stream_name, token, row = received_rows.pop(0) self.assertEqual("events", stream_name) self.assertIsInstance(row, EventsStreamRow) - self.assertEqual(row.type, "state") - self.assertIsInstance(row.data, EventsStreamCurrentStateRow) - state_rows.append(row.data) - - state_rows.sort(key=lambda r: r.state_key) - - sr = state_rows.pop(0) - self.assertEqual(sr.type, EventTypes.PowerLevels) - self.assertEqual(sr.event_id, pl_event.event_id) - for sr in state_rows: - self.assertEqual(sr.type, "test_state_event") - # "None" indicates the state has been deleted - self.assertIsNone(sr.event_id) + self.assertEqual(row.type, "ev") + self.assertIsInstance(row.data, EventsStreamEventRow) + self.assertEqual(row.data.event_id, pl_event.event_id) + + # the state rows are unsorted + state_rows: List[EventsStreamCurrentStateRow] = [] + for stream_name, _, row in received_rows: + self.assertEqual("events", stream_name) + self.assertIsInstance(row, EventsStreamRow) + self.assertEqual(row.type, "state") + self.assertIsInstance(row.data, EventsStreamCurrentStateRow) + state_rows.append(row.data) + + state_rows.sort(key=lambda r: r.state_key) + + sr = state_rows.pop(0) + self.assertEqual(sr.type, EventTypes.PowerLevels) + self.assertEqual(sr.event_id, pl_event.event_id) + for sr in state_rows: + self.assertEqual(sr.type, "test_state_event") + # "None" indicates the state has been deleted + self.assertIsNone(sr.event_id) def test_update_function_state_row_limit(self) -> None: """Test replication with many state events over several stream ids.""" -- cgit 1.4.1