diff options
| -rw-r--r-- | changelog.d/9640.misc | 1 | ||||
| -rw-r--r-- | synapse/federation/federation_server.py | 25 | ||||
| -rw-r--r-- | synapse/federation/sender/per_destination_queue.py | 104 | ||||
| -rw-r--r-- | tests/federation/test_federation_catch_up.py | 49 |
4 files changed, 141 insertions, 38 deletions
diff --git a/changelog.d/9640.misc b/changelog.d/9640.misc new file mode 100644 index 0000000000..3d410ed4cd --- /dev/null +++ b/changelog.d/9640.misc @@ -0,0 +1 @@ +Improve performance of federation catch up by sending events the latest events in the room to the remote, rather than just the last event sent by the local server. diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py index 9839d3d016..d84e362070 100644 --- a/synapse/federation/federation_server.py +++ b/synapse/federation/federation_server.py @@ -35,7 +35,7 @@ from twisted.internet import defer from twisted.internet.abstract import isIPAddress from twisted.python import failure -from synapse.api.constants import EduTypes, EventTypes, Membership +from synapse.api.constants import EduTypes, EventTypes from synapse.api.errors import ( AuthError, Codes, @@ -63,7 +63,7 @@ from synapse.replication.http.federation import ( ReplicationFederationSendEduRestServlet, ReplicationGetQueryRestServlet, ) -from synapse.types import JsonDict, get_domain_from_id +from synapse.types import JsonDict from synapse.util import glob_to_regex, json_decoder, unwrapFirstError from synapse.util.async_helpers import Linearizer, concurrently_execute from synapse.util.caches.response_cache import ResponseCache @@ -727,27 +727,6 @@ class FederationServer(FederationBase): if the event was unacceptable for any other reason (eg, too large, too many prev_events, couldn't find the prev_events) """ - # check that it's actually being sent from a valid destination to - # workaround bug #1753 in 0.18.5 and 0.18.6 - if origin != get_domain_from_id(pdu.sender): - # We continue to accept join events from any server; this is - # necessary for the federation join dance to work correctly. - # (When we join over federation, the "helper" server is - # responsible for sending out the join event, rather than the - # origin. See bug #1893. This is also true for some third party - # invites). - if not ( - pdu.type == "m.room.member" - and pdu.content - and pdu.content.get("membership", None) - in (Membership.JOIN, Membership.INVITE) - ): - logger.info( - "Discarding PDU %s from invalid origin %s", pdu.event_id, origin - ) - return - else: - logger.info("Accepting join PDU %s from %s", pdu.event_id, origin) # We've already checked that we know the room version by this point room_version = await self.store.get_room_version(pdu.room_id) diff --git a/synapse/federation/sender/per_destination_queue.py b/synapse/federation/sender/per_destination_queue.py index cc0d765e5f..af85fe0a1e 100644 --- a/synapse/federation/sender/per_destination_queue.py +++ b/synapse/federation/sender/per_destination_queue.py @@ -15,7 +15,7 @@ # limitations under the License. import datetime import logging -from typing import TYPE_CHECKING, Dict, Hashable, Iterable, List, Optional, Tuple, cast +from typing import TYPE_CHECKING, Dict, Hashable, Iterable, List, Optional, Tuple import attr from prometheus_client import Counter @@ -77,6 +77,7 @@ class PerDestinationQueue: self._transaction_manager = transaction_manager self._instance_name = hs.get_instance_name() self._federation_shard_config = hs.config.worker.federation_shard_config + self._state = hs.get_state_handler() self._should_send_on_this_instance = True if not self._federation_shard_config.should_handle( @@ -415,22 +416,95 @@ class PerDestinationQueue: "This should not happen." % event_ids ) - if logger.isEnabledFor(logging.INFO): - rooms = [p.room_id for p in catchup_pdus] - logger.info("Catching up rooms to %s: %r", self._destination, rooms) + # We send transactions with events from one room only, as its likely + # that the remote will have to do additional processing, which may + # take some time. It's better to give it small amounts of work + # rather than risk the request timing out and repeatedly being + # retried, and not making any progress. + # + # Note: `catchup_pdus` will have exactly one PDU per room. + for pdu in catchup_pdus: + # The PDU from the DB will be the last PDU in the room from + # *this server* that wasn't sent to the remote. However, other + # servers may have sent lots of events since then, and we want + # to try and tell the remote only about the *latest* events in + # the room. This is so that it doesn't get inundated by events + # from various parts of the DAG, which all need to be processed. + # + # Note: this does mean that in large rooms a server coming back + # online will get sent the same events from all the different + # servers, but the remote will correctly deduplicate them and + # handle it only once. + + # Step 1, fetch the current extremities + extrems = await self._store.get_prev_events_for_room(pdu.room_id) + + if pdu.event_id in extrems: + # If the event is in the extremities, then great! We can just + # use that without having to do further checks. + room_catchup_pdus = [pdu] + else: + # If not, fetch the extremities and figure out which we can + # send. + extrem_events = await self._store.get_events_as_list(extrems) + + new_pdus = [] + for p in extrem_events: + # We pulled this from the DB, so it'll be non-null + assert p.internal_metadata.stream_ordering + + # Filter out events that happened before the remote went + # offline + if ( + p.internal_metadata.stream_ordering + < self._last_successful_stream_ordering + ): + continue - await self._transaction_manager.send_new_transaction( - self._destination, catchup_pdus, [] - ) + # Filter out events where the server is not in the room, + # e.g. it may have left/been kicked. *Ideally* we'd pull + # out the kick and send that, but it's a rare edge case + # so we don't bother for now (the server that sent the + # kick should send it out if its online). + hosts = await self._state.get_hosts_in_room_at_events( + p.room_id, [p.event_id] + ) + if self._destination not in hosts: + continue - sent_transactions_counter.inc() - final_pdu = catchup_pdus[-1] - self._last_successful_stream_ordering = cast( - int, final_pdu.internal_metadata.stream_ordering - ) - await self._store.set_destination_last_successful_stream_ordering( - self._destination, self._last_successful_stream_ordering - ) + new_pdus.append(p) + + # If we've filtered out all the extremities, fall back to + # sending the original event. This should ensure that the + # server gets at least some of missed events (especially if + # the other sending servers are up). + if new_pdus: + room_catchup_pdus = new_pdus + + logger.info( + "Catching up rooms to %s: %r", self._destination, pdu.room_id + ) + + await self._transaction_manager.send_new_transaction( + self._destination, room_catchup_pdus, [] + ) + + sent_transactions_counter.inc() + + # We pulled this from the DB, so it'll be non-null + assert pdu.internal_metadata.stream_ordering + + # Note that we mark the last successful stream ordering as that + # from the *original* PDU, rather than the PDU(s) we actually + # send. This is because we use it to mark our position in the + # queue of missed PDUs to process. + self._last_successful_stream_ordering = ( + pdu.internal_metadata.stream_ordering + ) + + await self._store.set_destination_last_successful_stream_ordering( + self._destination, self._last_successful_stream_ordering + ) def _get_rr_edus(self, force_flush: bool) -> Iterable[Edu]: if not self._pending_rrs: diff --git a/tests/federation/test_federation_catch_up.py b/tests/federation/test_federation_catch_up.py index 6f96cd7940..95eac6a5a3 100644 --- a/tests/federation/test_federation_catch_up.py +++ b/tests/federation/test_federation_catch_up.py @@ -2,6 +2,7 @@ from typing import List, Tuple from mock import Mock +from synapse.api.constants import EventTypes from synapse.events import EventBase from synapse.federation.sender import PerDestinationQueue, TransactionManager from synapse.federation.units import Edu @@ -421,3 +422,51 @@ class FederationCatchUpTestCases(FederatingHomeserverTestCase): self.assertNotIn("zzzerver", woken) # - all destinations are woken exactly once; they appear once in woken. self.assertCountEqual(woken, server_names[:-1]) + + @override_config({"send_federation": True}) + def test_not_latest_event(self): + """Test that we send the latest event in the room even if its not ours.""" + + per_dest_queue, sent_pdus = self.make_fake_destination_queue() + + # Make a room with a local user, and two servers. One will go offline + # and one will send some events. + self.register_user("u1", "you the one") + u1_token = self.login("u1", "you the one") + room_1 = self.helper.create_room_as("u1", tok=u1_token) + + self.get_success( + event_injection.inject_member_event(self.hs, room_1, "@user:host2", "join") + ) + event_1 = self.get_success( + event_injection.inject_member_event(self.hs, room_1, "@user:host3", "join") + ) + + # First we send something from the local server, so that we notice the + # remote is down and go into catchup mode. + self.helper.send(room_1, "you hear me!!", tok=u1_token) + + # Now simulate us receiving an event from the still online remote. + event_2 = self.get_success( + event_injection.inject_event( + self.hs, + type=EventTypes.Message, + sender="@user:host3", + room_id=room_1, + content={"msgtype": "m.text", "body": "Hello"}, + ) + ) + + self.get_success( + self.hs.get_datastore().set_destination_last_successful_stream_ordering( + "host2", event_1.internal_metadata.stream_ordering + ) + ) + + self.get_success(per_dest_queue._catch_up_transmission_loop()) + + # We expect only the last message from the remote, event_2, to have been + # sent, rather than the last *local* event that was sent. + self.assertEqual(len(sent_pdus), 1) + self.assertEqual(sent_pdus[0].event_id, event_2.event_id) + self.assertFalse(per_dest_queue._catching_up) |