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Instrument the federation/backfill part of /messages (#13489)

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Instrument the federation/backfill part of `/messages` so it's easier to follow what's going on in Jaeger when viewing a trace.

Split out from https://github.com/matrix-org/synapse/pull/13440

Follow-up from https://github.com/matrix-org/synapse/pull/13368

Part of https://github.com/matrix-org/synapse/issues/13356
This commit is contained in:
Eric Eastwood 2022-08-16 12:39:40 -05:00 committed by GitHub
parent 5ace5d7b15
commit 0a4efbc1dd
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GPG key ID: 4AEE18F83AFDEB23
11 changed files with 220 additions and 33 deletions
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1
changelog.d/13489.misc Normal file
View file

@ -0,0 +1 @@
Instrument the federation/backfill part of `/messages` for understandable traces in Jaeger.

27
synapse/federation/federation_client.py
View file

@ -61,7 +61,7 @@ from synapse.federation.federation_base import (
)
from synapse.federation.transport.client import SendJoinResponse
from synapse.http.types import QueryParams
from synapse.logging.opentracing import trace
from synapse.logging.opentracing import SynapseTags, set_tag, tag_args, trace
from synapse.types import JsonDict, UserID, get_domain_from_id
from synapse.util.async_helpers import concurrently_execute
from synapse.util.caches.expiringcache import ExpiringCache
@ -235,6 +235,7 @@ class FederationClient(FederationBase):
)
@trace
@tag_args
async def backfill(
self, dest: str, room_id: str, limit: int, extremities: Collection[str]
) -> Optional[List[EventBase]]:
@ -337,6 +338,8 @@ class FederationClient(FederationBase):
return None
@trace
@tag_args
async def get_pdu(
self,
destinations: Iterable[str],
@ -448,6 +451,8 @@ class FederationClient(FederationBase):
return event_copy
@trace
@tag_args
async def get_room_state_ids(
self, destination: str, room_id: str, event_id: str
) -> Tuple[List[str], List[str]]:
@ -467,6 +472,23 @@ class FederationClient(FederationBase):
state_event_ids = result["pdu_ids"]
auth_event_ids = result.get("auth_chain_ids", [])
set_tag(
SynapseTags.RESULT_PREFIX + "state_event_ids",
str(state_event_ids),
)
set_tag(
SynapseTags.RESULT_PREFIX + "state_event_ids.length",
str(len(state_event_ids)),
)
set_tag(
SynapseTags.RESULT_PREFIX + "auth_event_ids",
str(auth_event_ids),
)
set_tag(
SynapseTags.RESULT_PREFIX + "auth_event_ids.length",
str(len(auth_event_ids)),
)
if not isinstance(state_event_ids, list) or not isinstance(
auth_event_ids, list
):
@ -474,6 +496,8 @@ class FederationClient(FederationBase):
return state_event_ids, auth_event_ids
@trace
@tag_args
async def get_room_state(
self,
destination: str,
@ -533,6 +557,7 @@ class FederationClient(FederationBase):
return valid_state_events, valid_auth_events
@trace
async def _check_sigs_and_hash_and_fetch(
self,
origin: str,

10
synapse/handlers/federation.py
View file

@ -59,7 +59,7 @@ from synapse.events.validator import EventValidator
from synapse.federation.federation_client import InvalidResponseError
from synapse.http.servlet import assert_params_in_dict
from synapse.logging.context import nested_logging_context
from synapse.logging.opentracing import tag_args, trace
from synapse.logging.opentracing import SynapseTags, set_tag, tag_args, trace
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.module_api import NOT_SPAM
from synapse.replication.http.federation import (
@ -370,6 +370,14 @@ class FederationHandler:
logger.debug(
"_maybe_backfill_inner: extremities_to_request %s", extremities_to_request
)
set_tag(
SynapseTags.RESULT_PREFIX + "extremities_to_request",
str(extremities_to_request),
)
set_tag(
SynapseTags.RESULT_PREFIX + "extremities_to_request.length",
str(len(extremities_to_request)),
)
# Now we need to decide which hosts to hit first.

112
synapse/handlers/federation_event.py
View file

@ -59,7 +59,13 @@ from synapse.events import EventBase
from synapse.events.snapshot import EventContext
from synapse.federation.federation_client import InvalidResponseError
from synapse.logging.context import nested_logging_context
from synapse.logging.opentracing import trace
from synapse.logging.opentracing import (
SynapseTags,
set_tag,
start_active_span,
tag_args,
trace,
)
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.replication.http.devices import ReplicationUserDevicesResyncRestServlet
from synapse.replication.http.federation import (
@ -410,6 +416,7 @@ class FederationEventHandler:
prev_member_event,
)
@trace
async def process_remote_join(
self,
origin: str,
@ -715,7 +722,7 @@ class FederationEventHandler:
@trace
async def _process_pulled_events(
self, origin: str, events: Iterable[EventBase], backfilled: bool
self, origin: str, events: Collection[EventBase], backfilled: bool
) -> None:
"""Process a batch of events we have pulled from a remote server
@ -730,6 +737,15 @@ class FederationEventHandler:
backfilled: True if this is part of a historical batch of events (inhibits
notification to clients, and validation of device keys.)
"""
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids",
str([event.event_id for event in events]),
)
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
str(len(events)),
)
set_tag(SynapseTags.FUNC_ARG_PREFIX + "backfilled", str(backfilled))
logger.debug(
"processing pulled backfilled=%s events=%s",
backfilled,
@ -753,6 +769,7 @@ class FederationEventHandler:
await self._process_pulled_event(origin, ev, backfilled=backfilled)
@trace
@tag_args
async def _process_pulled_event(
self, origin: str, event: EventBase, backfilled: bool
) -> None:
@ -854,6 +871,7 @@ class FederationEventHandler:
else:
raise
@trace
async def _compute_event_context_with_maybe_missing_prevs(
self, dest: str, event: EventBase
) -> EventContext:
@ -970,6 +988,8 @@ class FederationEventHandler:
event, state_ids_before_event=state_map, partial_state=partial_state
)
@trace
@tag_args
async def _get_state_ids_after_missing_prev_event(
self,
destination: str,
@ -1009,10 +1029,10 @@ class FederationEventHandler:
logger.debug("Fetching %i events from cache/store", len(desired_events))
have_events = await self._store.have_seen_events(room_id, desired_events)
missing_desired_events = desired_events - have_events
missing_desired_event_ids = desired_events - have_events
logger.debug(
"We are missing %i events (got %i)",
len(missing_desired_events),
len(missing_desired_event_ids),
len(have_events),
)
@ -1024,13 +1044,30 @@ class FederationEventHandler:
# already have a bunch of the state events. It would be nice if the
# federation api gave us a way of finding out which we actually need.
missing_auth_events = set(auth_event_ids) - have_events
missing_auth_events.difference_update(
await self._store.have_seen_events(room_id, missing_auth_events)
missing_auth_event_ids = set(auth_event_ids) - have_events
missing_auth_event_ids.difference_update(
await self._store.have_seen_events(room_id, missing_auth_event_ids)
)
logger.debug("We are also missing %i auth events", len(missing_auth_events))
logger.debug("We are also missing %i auth events", len(missing_auth_event_ids))
missing_events = missing_desired_events | missing_auth_events
missing_event_ids = missing_desired_event_ids | missing_auth_event_ids
set_tag(
SynapseTags.RESULT_PREFIX + "missing_auth_event_ids",
str(missing_auth_event_ids),
)
set_tag(
SynapseTags.RESULT_PREFIX + "missing_auth_event_ids.length",
str(len(missing_auth_event_ids)),
)
set_tag(
SynapseTags.RESULT_PREFIX + "missing_desired_event_ids",
str(missing_desired_event_ids),
)
set_tag(
SynapseTags.RESULT_PREFIX + "missing_desired_event_ids.length",
str(len(missing_desired_event_ids)),
)
# Making an individual request for each of 1000s of events has a lot of
# overhead. On the other hand, we don't really want to fetch all of the events
@ -1041,13 +1078,13 @@ class FederationEventHandler:
#
# TODO: might it be better to have an API which lets us do an aggregate event
# request
if (len(missing_events) * 10) >= len(auth_event_ids) + len(state_event_ids):
if (len(missing_event_ids) * 10) >= len(auth_event_ids) + len(state_event_ids):
logger.debug("Requesting complete state from remote")
await self._get_state_and_persist(destination, room_id, event_id)
else:
logger.debug("Fetching %i events from remote", len(missing_events))
logger.debug("Fetching %i events from remote", len(missing_event_ids))
await self._get_events_and_persist(
destination=destination, room_id=room_id, event_ids=missing_events
destination=destination, room_id=room_id, event_ids=missing_event_ids
)
# We now need to fill out the state map, which involves fetching the
@ -1104,6 +1141,14 @@ class FederationEventHandler:
event_id,
failed_to_fetch,
)
set_tag(
SynapseTags.RESULT_PREFIX + "failed_to_fetch",
str(failed_to_fetch),
)
set_tag(
SynapseTags.RESULT_PREFIX + "failed_to_fetch.length",
str(len(failed_to_fetch)),
)
if remote_event.is_state() and remote_event.rejected_reason is None:
state_map[
@ -1112,6 +1157,8 @@ class FederationEventHandler:
return state_map
@trace
@tag_args
async def _get_state_and_persist(
self, destination: str, room_id: str, event_id: str
) -> None:
@ -1133,6 +1180,7 @@ class FederationEventHandler:
destination=destination, room_id=room_id, event_ids=(event_id,)
)
@trace
async def _process_received_pdu(
self,
origin: str,
@ -1283,6 +1331,7 @@ class FederationEventHandler:
except Exception:
logger.exception("Failed to resync device for %s", sender)
@trace
async def _handle_marker_event(self, origin: str, marker_event: EventBase) -> None:
"""Handles backfilling the insertion event when we receive a marker
event that points to one.
@ -1414,6 +1463,8 @@ class FederationEventHandler:
return event_from_response
@trace
@tag_args
async def _get_events_and_persist(
self, destination: str, room_id: str, event_ids: Collection[str]
) -> None:
@ -1459,6 +1510,7 @@ class FederationEventHandler:
logger.info("Fetched %i events of %i requested", len(events), len(event_ids))
await self._auth_and_persist_outliers(room_id, events)
@trace
async def _auth_and_persist_outliers(
self, room_id: str, events: Iterable[EventBase]
) -> None:
@ -1477,6 +1529,16 @@ class FederationEventHandler:
"""
event_map = {event.event_id: event for event in events}
event_ids = event_map.keys()
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids",
str(event_ids),
)
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
str(len(event_ids)),
)
# filter out any events we have already seen. This might happen because
# the events were eagerly pushed to us (eg, during a room join), or because
# another thread has raced against us since we decided to request the event.
@ -1593,6 +1655,7 @@ class FederationEventHandler:
backfilled=True,
)
@trace
async def _check_event_auth(
self, origin: Optional[str], event: EventBase, context: EventContext
) -> None:
@ -1631,6 +1694,14 @@ class FederationEventHandler:
claimed_auth_events = await self._load_or_fetch_auth_events_for_event(
origin, event
)
set_tag(
SynapseTags.RESULT_PREFIX + "claimed_auth_events",
str([ev.event_id for ev in claimed_auth_events]),
)
set_tag(
SynapseTags.RESULT_PREFIX + "claimed_auth_events.length",
str(len(claimed_auth_events)),
)
# ... and check that the event passes auth at those auth events.
# https://spec.matrix.org/v1.3/server-server-api/#checks-performed-on-receipt-of-a-pdu:
@ -1728,6 +1799,7 @@ class FederationEventHandler:
)
context.rejected = RejectedReason.AUTH_ERROR
@trace
async def _maybe_kick_guest_users(self, event: EventBase) -> None:
if event.type != EventTypes.GuestAccess:
return
@ -1935,6 +2007,8 @@ class FederationEventHandler:
# instead we raise an AuthError, which will make the caller ignore it.
raise AuthError(code=HTTPStatus.FORBIDDEN, msg="Auth events could not be found")
@trace
@tag_args
async def _get_remote_auth_chain_for_event(
self, destination: str, room_id: str, event_id: str
) -> None:
@ -1963,6 +2037,7 @@ class FederationEventHandler:
await self._auth_and_persist_outliers(room_id, remote_auth_events)
@trace
async def _run_push_actions_and_persist_event(
self, event: EventBase, context: EventContext, backfilled: bool = False
) -> None:
@ -2071,8 +2146,17 @@ class FederationEventHandler:
self._message_handler.maybe_schedule_expiry(event)
if not backfilled: # Never notify for backfilled events
for event in events:
await self._notify_persisted_event(event, max_stream_token)
with start_active_span("notify_persisted_events"):
set_tag(
SynapseTags.RESULT_PREFIX + "event_ids",
str([ev.event_id for ev in events]),
)
set_tag(
SynapseTags.RESULT_PREFIX + "event_ids.length",
str(len(events)),
)
for event in events:
await self._notify_persisted_event(event, max_stream_token)
return max_stream_token.stream

19
synapse/logging/opentracing.py
View file

@ -310,6 +310,19 @@ class SynapseTags:
# The name of the external cache
CACHE_NAME = "cache.name"
# Used to tag function arguments
#
# Tag a named arg. The name of the argument should be appended to this prefix.
FUNC_ARG_PREFIX = "ARG."
# Tag extra variadic number of positional arguments (`def foo(first, second, *extras)`)
FUNC_ARGS = "args"
# Tag keyword args
FUNC_KWARGS = "kwargs"
# Some intermediate result that's interesting to the function. The label for
# the result should be appended to this prefix.
RESULT_PREFIX = "RESULT."
class SynapseBaggage:
FORCE_TRACING = "synapse-force-tracing"
@ -967,9 +980,9 @@ def tag_args(func: Callable[P, R]) -> Callable[P, R]:
# first argument only if it's named `self` or `cls`. This isn't fool-proof
# but handles the idiomatic cases.
for i, arg in enumerate(args[1:], start=1): # type: ignore[index]
set_tag("ARG_" + argspec.args[i], str(arg))
set_tag("args", str(args[len(argspec.args) :])) # type: ignore[index]
set_tag("kwargs", str(kwargs))
set_tag(SynapseTags.FUNC_ARG_PREFIX + argspec.args[i], str(arg))
set_tag(SynapseTags.FUNC_ARGS, str(args[len(argspec.args) :])) # type: ignore[index]
set_tag(SynapseTags.FUNC_KWARGS, str(kwargs))
yield
return _custom_sync_async_decorator(func, _wrapping_logic)

30
synapse/storage/controllers/persist_events.py
View file

@ -45,8 +45,14 @@ from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership
from synapse.events import EventBase
from synapse.events.snapshot import EventContext
from synapse.logging import opentracing
from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
from synapse.logging.opentracing import (
SynapseTags,
active_span,
set_tag,
start_active_span_follows_from,
trace,
)
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.storage.controllers.state import StateStorageController
from synapse.storage.databases import Databases
@ -223,7 +229,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
queue.append(end_item)
# also add our active opentracing span to the item so that we get a link back
span = opentracing.active_span()
span = active_span()
if span:
end_item.parent_opentracing_span_contexts.append(span.context)
@ -234,7 +240,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
res = await make_deferred_yieldable(end_item.deferred.observe())
# add another opentracing span which links to the persist trace.
with opentracing.start_active_span_follows_from(
with start_active_span_follows_from(
f"{task.name}_complete", (end_item.opentracing_span_context,)
):
pass
@ -266,7 +272,7 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
queue = self._get_drainining_queue(room_id)
for item in queue:
try:
with opentracing.start_active_span_follows_from(
with start_active_span_follows_from(
item.task.name,
item.parent_opentracing_span_contexts,
inherit_force_tracing=True,
@ -355,7 +361,7 @@ class EventsPersistenceStorageController:
f"Found an unexpected task type in event persistence queue: {task}"
)
@opentracing.trace
@trace
async def persist_events(
self,
events_and_contexts: Iterable[Tuple[EventBase, EventContext]],
@ -380,9 +386,21 @@ class EventsPersistenceStorageController:
PartialStateConflictError: if attempting to persist a partial state event in
a room that has been un-partial stated.
"""
event_ids: List[str] = []
partitioned: Dict[str, List[Tuple[EventBase, EventContext]]] = {}
for event, ctx in events_and_contexts:
partitioned.setdefault(event.room_id, []).append((event, ctx))
event_ids.append(event.event_id)
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids",
str(event_ids),
)
set_tag(
SynapseTags.FUNC_ARG_PREFIX + "event_ids.length",
str(len(event_ids)),
)
set_tag(SynapseTags.FUNC_ARG_PREFIX + "backfilled", str(backfilled))
async def enqueue(
item: Tuple[str, List[Tuple[EventBase, EventContext]]]
@ -418,7 +436,7 @@ class EventsPersistenceStorageController:
self.main_store.get_room_max_token(),
)
@opentracing.trace
@trace
async def persist_event(
self, event: EventBase, context: EventContext, backfilled: bool = False
) -> Tuple[EventBase, PersistedEventPosition, RoomStreamToken]:

5
synapse/storage/controllers/state.py
View file

@ -29,7 +29,7 @@ from typing import (
from synapse.api.constants import EventTypes
from synapse.events import EventBase
from synapse.logging.opentracing import trace
from synapse.logging.opentracing import tag_args, trace
from synapse.storage.roommember import ProfileInfo
from synapse.storage.state import StateFilter
from synapse.storage.util.partial_state_events_tracker import (
@ -229,6 +229,7 @@ class StateStorageController:
return {event: event_to_state[event] for event in event_ids}
@trace
@tag_args
async def get_state_ids_for_events(
self,
event_ids: Collection[str],
@ -333,6 +334,7 @@ class StateStorageController:
)
@trace
@tag_args
async def get_state_group_for_events(
self,
event_ids: Collection[str],
@ -474,6 +476,7 @@ class StateStorageController:
prev_stream_id, max_stream_id
)
@trace
async def get_current_state(
self, room_id: str, state_filter: Optional[StateFilter] = None
) -> StateMap[EventBase]:

6
synapse/storage/databases/main/event_federation.py
View file

@ -712,6 +712,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
# Return all events where not all sets can reach them.
return {eid for eid, n in event_to_missing_sets.items() if n}
@trace
@tag_args
async def get_oldest_event_ids_with_depth_in_room(
self, room_id: str
) -> List[Tuple[str, int]]:
@ -770,6 +772,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
room_id,
)
@trace
async def get_insertion_event_backward_extremities_in_room(
self, room_id: str
) -> List[Tuple[str, int]]:
@ -1342,6 +1345,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
event_results.reverse()
return event_results
@trace
@tag_args
async def get_successor_events(self, event_id: str) -> List[str]:
"""Fetch all events that have the given event as a prev event
@ -1378,6 +1383,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas
_delete_old_forward_extrem_cache_txn,
)
@trace
async def insert_insertion_extremity(self, event_id: str, room_id: str) -> None:
await self.db_pool.simple_upsert(
table="insertion_event_extremities",

2
synapse/storage/databases/main/events.py
View file

@ -40,6 +40,7 @@ from synapse.api.errors import Codes, SynapseError
from synapse.api.room_versions import RoomVersions
from synapse.events import EventBase, relation_from_event
from synapse.events.snapshot import EventContext
from synapse.logging.opentracing import trace
from synapse.storage._base import db_to_json, make_in_list_sql_clause
from synapse.storage.database import (
DatabasePool,
@ -145,6 +146,7 @@ class PersistEventsStore:
self._backfill_id_gen: AbstractStreamIdGenerator = self.store._backfill_id_gen
self._stream_id_gen: AbstractStreamIdGenerator = self.store._stream_id_gen
@trace
async def _persist_events_and_state_updates(
self,
events_and_contexts: List[Tuple[EventBase, EventContext]],

38
synapse/storage/databases/main/events_worker.py
View file

@ -54,6 +54,7 @@ from synapse.logging.context import (
current_context,
make_deferred_yieldable,
)
from synapse.logging.opentracing import start_active_span, tag_args, trace
from synapse.metrics.background_process_metrics import (
run_as_background_process,
wrap_as_background_process,
@ -430,6 +431,8 @@ class EventsWorkerStore(SQLBaseStore):
return {e.event_id: e for e in events}
@trace
@tag_args
async def get_events_as_list(
self,
event_ids: Collection[str],
@ -1090,23 +1093,42 @@ class EventsWorkerStore(SQLBaseStore):
"""
fetched_event_ids: Set[str] = set()
fetched_events: Dict[str, _EventRow] = {}
events_to_fetch = event_ids
while events_to_fetch:
row_map = await self._enqueue_events(events_to_fetch)
async def _fetch_event_ids_and_get_outstanding_redactions(
event_ids_to_fetch: Collection[str],
) -> Collection[str]:
"""
Fetch all of the given event_ids and return any associated redaction event_ids
that we still need to fetch in the next iteration.
"""
row_map = await self._enqueue_events(event_ids_to_fetch)
# we need to recursively fetch any redactions of those events
redaction_ids: Set[str] = set()
for event_id in events_to_fetch:
for event_id in event_ids_to_fetch:
row = row_map.get(event_id)
fetched_event_ids.add(event_id)
if row:
fetched_events[event_id] = row
redaction_ids.update(row.redactions)
events_to_fetch = redaction_ids.difference(fetched_event_ids)
if events_to_fetch:
logger.debug("Also fetching redaction events %s", events_to_fetch)
event_ids_to_fetch = redaction_ids.difference(fetched_event_ids)
return event_ids_to_fetch
# Grab the initial list of events requested
event_ids_to_fetch = await _fetch_event_ids_and_get_outstanding_redactions(
event_ids
)
# Then go and recursively find all of the associated redactions
with start_active_span("recursively fetching redactions"):
while event_ids_to_fetch:
logger.debug("Also fetching redaction events %s", event_ids_to_fetch)
event_ids_to_fetch = (
await _fetch_event_ids_and_get_outstanding_redactions(
event_ids_to_fetch
)
)
# build a map from event_id to EventBase
event_map: Dict[str, EventBase] = {}
@ -1424,6 +1446,8 @@ class EventsWorkerStore(SQLBaseStore):
return {r["event_id"] for r in rows}
@trace
@tag_args
async def have_seen_events(
self, room_id: str, event_ids: Iterable[str]
) -> Set[str]:

3
synapse/storage/util/partial_state_events_tracker.py
View file

@ -20,6 +20,7 @@ from twisted.internet import defer
from twisted.internet.defer import Deferred
from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
from synapse.logging.opentracing import trace_with_opname
from synapse.storage.databases.main.events_worker import EventsWorkerStore
from synapse.storage.databases.main.room import RoomWorkerStore
from synapse.util import unwrapFirstError
@ -58,6 +59,7 @@ class PartialStateEventsTracker:
for o in observers:
o.callback(None)
@trace_with_opname("PartialStateEventsTracker.await_full_state")
async def await_full_state(self, event_ids: Collection[str]) -> None:
"""Wait for all the given events to have full state.
@ -151,6 +153,7 @@ class PartialCurrentStateTracker:
for o in observers:
o.callback(None)
@trace_with_opname("PartialCurrentStateTracker.await_full_state")
async def await_full_state(self, room_id: str) -> None:
# We add the deferred immediately so that the DB call to check for
# partial state doesn't race when we unpartial the room.