mirror of
https://mau.dev/maunium/synapse.git
synced 2024-08-21 17:55:37 +00:00
Move persist_events out from main data store.
This is in preparation for splitting out of state_groups_state from the main store into it own one, as persisting events depends on calculating state.
This commit is contained in:
parent
409c62b27b
commit
22a9847670
@ -17,14 +17,14 @@
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import itertools
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import logging
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from collections import Counter as c_counter, OrderedDict, deque, namedtuple
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from collections import Counter as c_counter, OrderedDict, namedtuple
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from functools import wraps
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from six import iteritems, text_type
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from six.moves import range
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from canonicaljson import json
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from prometheus_client import Counter, Histogram
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from prometheus_client import Counter
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from twisted.internet import defer
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@ -34,11 +34,9 @@ from synapse.api.errors import SynapseError
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from synapse.events import EventBase # noqa: F401
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from synapse.events.snapshot import EventContext # noqa: F401
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from synapse.events.utils import prune_event_dict
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from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
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from synapse.logging.utils import log_function
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from synapse.metrics import BucketCollector
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from synapse.metrics.background_process_metrics import run_as_background_process
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from synapse.state import StateResolutionStore
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from synapse.storage._base import make_in_list_sql_clause
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from synapse.storage.background_updates import BackgroundUpdateStore
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from synapse.storage.data_stores.main.event_federation import EventFederationStore
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@ -46,10 +44,8 @@ from synapse.storage.data_stores.main.events_worker import EventsWorkerStore
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from synapse.storage.data_stores.main.state import StateGroupWorkerStore
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from synapse.types import RoomStreamToken, get_domain_from_id
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from synapse.util import batch_iter
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from synapse.util.async_helpers import ObservableDeferred
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from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
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from synapse.util.frozenutils import frozendict_json_encoder
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from synapse.util.metrics import Measure
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logger = logging.getLogger(__name__)
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@ -60,37 +56,6 @@ event_counter = Counter(
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["type", "origin_type", "origin_entity"],
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)
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# The number of times we are recalculating the current state
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state_delta_counter = Counter("synapse_storage_events_state_delta", "")
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# The number of times we are recalculating state when there is only a
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# single forward extremity
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state_delta_single_event_counter = Counter(
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"synapse_storage_events_state_delta_single_event", ""
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)
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# The number of times we are reculating state when we could have resonably
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# calculated the delta when we calculated the state for an event we were
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# persisting.
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state_delta_reuse_delta_counter = Counter(
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"synapse_storage_events_state_delta_reuse_delta", ""
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)
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# The number of forward extremities for each new event.
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forward_extremities_counter = Histogram(
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"synapse_storage_events_forward_extremities_persisted",
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"Number of forward extremities for each new event",
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buckets=(1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"),
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)
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# The number of stale forward extremities for each new event. Stale extremities
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# are those that were in the previous set of extremities as well as the new.
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stale_forward_extremities_counter = Histogram(
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"synapse_storage_events_stale_forward_extremities_persisted",
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"Number of unchanged forward extremities for each new event",
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buckets=(0, 1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"),
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)
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def encode_json(json_object):
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"""
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@ -102,110 +67,6 @@ def encode_json(json_object):
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return out
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class _EventPeristenceQueue(object):
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"""Queues up events so that they can be persisted in bulk with only one
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concurrent transaction per room.
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"""
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_EventPersistQueueItem = namedtuple(
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"_EventPersistQueueItem", ("events_and_contexts", "backfilled", "deferred")
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)
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def __init__(self):
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self._event_persist_queues = {}
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self._currently_persisting_rooms = set()
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def add_to_queue(self, room_id, events_and_contexts, backfilled):
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"""Add events to the queue, with the given persist_event options.
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NB: due to the normal usage pattern of this method, it does *not*
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follow the synapse logcontext rules, and leaves the logcontext in
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place whether or not the returned deferred is ready.
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Args:
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room_id (str):
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events_and_contexts (list[(EventBase, EventContext)]):
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backfilled (bool):
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Returns:
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defer.Deferred: a deferred which will resolve once the events are
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persisted. Runs its callbacks *without* a logcontext.
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"""
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queue = self._event_persist_queues.setdefault(room_id, deque())
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if queue:
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# if the last item in the queue has the same `backfilled` setting,
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# we can just add these new events to that item.
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end_item = queue[-1]
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if end_item.backfilled == backfilled:
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end_item.events_and_contexts.extend(events_and_contexts)
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return end_item.deferred.observe()
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deferred = ObservableDeferred(defer.Deferred(), consumeErrors=True)
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queue.append(
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self._EventPersistQueueItem(
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events_and_contexts=events_and_contexts,
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backfilled=backfilled,
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deferred=deferred,
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)
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)
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return deferred.observe()
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def handle_queue(self, room_id, per_item_callback):
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"""Attempts to handle the queue for a room if not already being handled.
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The given callback will be invoked with for each item in the queue,
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of type _EventPersistQueueItem. The per_item_callback will continuously
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be called with new items, unless the queue becomnes empty. The return
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value of the function will be given to the deferreds waiting on the item,
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exceptions will be passed to the deferreds as well.
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This function should therefore be called whenever anything is added
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to the queue.
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If another callback is currently handling the queue then it will not be
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invoked.
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"""
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if room_id in self._currently_persisting_rooms:
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return
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self._currently_persisting_rooms.add(room_id)
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@defer.inlineCallbacks
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def handle_queue_loop():
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try:
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queue = self._get_drainining_queue(room_id)
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for item in queue:
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try:
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ret = yield per_item_callback(item)
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except Exception:
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with PreserveLoggingContext():
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item.deferred.errback()
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else:
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with PreserveLoggingContext():
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item.deferred.callback(ret)
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finally:
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queue = self._event_persist_queues.pop(room_id, None)
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if queue:
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self._event_persist_queues[room_id] = queue
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self._currently_persisting_rooms.discard(room_id)
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# set handle_queue_loop off in the background
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run_as_background_process("persist_events", handle_queue_loop)
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def _get_drainining_queue(self, room_id):
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queue = self._event_persist_queues.setdefault(room_id, deque())
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try:
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while True:
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yield queue.popleft()
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except IndexError:
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# Queue has been drained.
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pass
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_EventCacheEntry = namedtuple("_EventCacheEntry", ("event", "redacted_event"))
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@ -241,9 +102,6 @@ class EventsStore(
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def __init__(self, db_conn, hs):
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super(EventsStore, self).__init__(db_conn, hs)
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self._event_persist_queue = _EventPeristenceQueue()
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self._state_resolution_handler = hs.get_state_resolution_handler()
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# Collect metrics on the number of forward extremities that exist.
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# Counter of number of extremities to count
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self._current_forward_extremities_amount = c_counter()
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@ -286,80 +144,16 @@ class EventsStore(
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res = yield self.runInteraction("read_forward_extremities", fetch)
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self._current_forward_extremities_amount = c_counter(list(x[0] for x in res))
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@defer.inlineCallbacks
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def persist_events(self, events_and_contexts, backfilled=False):
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"""
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Write events to the database
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Args:
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events_and_contexts: list of tuples of (event, context)
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backfilled (bool): Whether the results are retrieved from federation
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via backfill or not. Used to determine if they're "new" events
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which might update the current state etc.
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Returns:
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Deferred[int]: the stream ordering of the latest persisted event
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"""
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partitioned = {}
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for event, ctx in events_and_contexts:
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partitioned.setdefault(event.room_id, []).append((event, ctx))
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deferreds = []
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for room_id, evs_ctxs in iteritems(partitioned):
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d = self._event_persist_queue.add_to_queue(
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room_id, evs_ctxs, backfilled=backfilled
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)
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deferreds.append(d)
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for room_id in partitioned:
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self._maybe_start_persisting(room_id)
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yield make_deferred_yieldable(
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defer.gatherResults(deferreds, consumeErrors=True)
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)
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max_persisted_id = yield self._stream_id_gen.get_current_token()
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return max_persisted_id
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@defer.inlineCallbacks
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@log_function
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def persist_event(self, event, context, backfilled=False):
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"""
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Args:
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event (EventBase):
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context (EventContext):
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backfilled (bool):
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Returns:
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Deferred: resolves to (int, int): the stream ordering of ``event``,
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and the stream ordering of the latest persisted event
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"""
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deferred = self._event_persist_queue.add_to_queue(
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event.room_id, [(event, context)], backfilled=backfilled
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)
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self._maybe_start_persisting(event.room_id)
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yield make_deferred_yieldable(deferred)
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max_persisted_id = yield self._stream_id_gen.get_current_token()
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return (event.internal_metadata.stream_ordering, max_persisted_id)
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def _maybe_start_persisting(self, room_id):
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@defer.inlineCallbacks
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def persisting_queue(item):
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with Measure(self._clock, "persist_events"):
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yield self._persist_events(
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item.events_and_contexts, backfilled=item.backfilled
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)
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self._event_persist_queue.handle_queue(room_id, persisting_queue)
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@_retry_on_integrity_error
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@defer.inlineCallbacks
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def _persist_events(
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self, events_and_contexts, backfilled=False, delete_existing=False
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self,
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events_and_contexts,
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current_state_for_room,
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state_delta_for_room,
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new_forward_extremeties,
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backfilled=False,
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delete_existing=False,
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):
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"""Persist events to db
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@ -374,135 +168,6 @@ class EventsStore(
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if not events_and_contexts:
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return
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chunks = [
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events_and_contexts[x : x + 100]
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for x in range(0, len(events_and_contexts), 100)
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]
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for chunk in chunks:
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# We can't easily parallelize these since different chunks
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# might contain the same event. :(
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# NB: Assumes that we are only persisting events for one room
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# at a time.
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# map room_id->list[event_ids] giving the new forward
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# extremities in each room
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new_forward_extremeties = {}
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# map room_id->(type,state_key)->event_id tracking the full
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# state in each room after adding these events.
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# This is simply used to prefill the get_current_state_ids
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# cache
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current_state_for_room = {}
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# map room_id->(to_delete, to_insert) where to_delete is a list
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# of type/state keys to remove from current state, and to_insert
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# is a map (type,key)->event_id giving the state delta in each
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# room
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state_delta_for_room = {}
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if not backfilled:
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with Measure(self._clock, "_calculate_state_and_extrem"):
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# Work out the new "current state" for each room.
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# We do this by working out what the new extremities are and then
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# calculating the state from that.
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events_by_room = {}
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for event, context in chunk:
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events_by_room.setdefault(event.room_id, []).append(
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(event, context)
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)
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for room_id, ev_ctx_rm in iteritems(events_by_room):
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latest_event_ids = yield self.get_latest_event_ids_in_room(
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room_id
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)
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new_latest_event_ids = yield self._calculate_new_extremities(
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room_id, ev_ctx_rm, latest_event_ids
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)
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latest_event_ids = set(latest_event_ids)
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if new_latest_event_ids == latest_event_ids:
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# No change in extremities, so no change in state
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continue
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# there should always be at least one forward extremity.
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# (except during the initial persistence of the send_join
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# results, in which case there will be no existing
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# extremities, so we'll `continue` above and skip this bit.)
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assert new_latest_event_ids, "No forward extremities left!"
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new_forward_extremeties[room_id] = new_latest_event_ids
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len_1 = (
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len(latest_event_ids) == 1
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and len(new_latest_event_ids) == 1
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)
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if len_1:
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all_single_prev_not_state = all(
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len(event.prev_event_ids()) == 1
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and not event.is_state()
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for event, ctx in ev_ctx_rm
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)
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# Don't bother calculating state if they're just
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# a long chain of single ancestor non-state events.
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if all_single_prev_not_state:
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continue
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state_delta_counter.inc()
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if len(new_latest_event_ids) == 1:
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state_delta_single_event_counter.inc()
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# This is a fairly handwavey check to see if we could
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# have guessed what the delta would have been when
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# processing one of these events.
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# What we're interested in is if the latest extremities
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# were the same when we created the event as they are
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# now. When this server creates a new event (as opposed
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# to receiving it over federation) it will use the
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# forward extremities as the prev_events, so we can
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# guess this by looking at the prev_events and checking
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# if they match the current forward extremities.
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for ev, _ in ev_ctx_rm:
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prev_event_ids = set(ev.prev_event_ids())
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if latest_event_ids == prev_event_ids:
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state_delta_reuse_delta_counter.inc()
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break
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logger.info("Calculating state delta for room %s", room_id)
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with Measure(
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self._clock, "persist_events.get_new_state_after_events"
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):
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res = yield self._get_new_state_after_events(
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room_id,
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ev_ctx_rm,
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latest_event_ids,
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new_latest_event_ids,
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)
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current_state, delta_ids = res
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# If either are not None then there has been a change,
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# and we need to work out the delta (or use that
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# given)
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if delta_ids is not None:
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# If there is a delta we know that we've
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# only added or replaced state, never
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# removed keys entirely.
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state_delta_for_room[room_id] = ([], delta_ids)
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elif current_state is not None:
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with Measure(
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self._clock, "persist_events.calculate_state_delta"
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):
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delta = yield self._calculate_state_delta(
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room_id, current_state
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)
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state_delta_for_room[room_id] = delta
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# If we have the current_state then lets prefill
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# the cache with it.
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if current_state is not None:
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current_state_for_room[room_id] = current_state
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# We want to calculate the stream orderings as late as possible, as
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# we only notify after all events with a lesser stream ordering have
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# been persisted. I.e. if we spend 10s inside the with block then
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@ -521,34 +186,36 @@ class EventsStore(
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# the same time for the same room.
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if backfilled:
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stream_ordering_manager = self._backfill_id_gen.get_next_mult(
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len(chunk)
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len(events_and_contexts)
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)
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else:
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stream_ordering_manager = self._stream_id_gen.get_next_mult(len(chunk))
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stream_ordering_manager = self._stream_id_gen.get_next_mult(
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len(events_and_contexts)
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)
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with stream_ordering_manager as stream_orderings:
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for (event, context), stream in zip(chunk, stream_orderings):
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for (event, context), stream in zip(events_and_contexts, stream_orderings):
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event.internal_metadata.stream_ordering = stream
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yield self.runInteraction(
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"persist_events",
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self._persist_events_txn,
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events_and_contexts=chunk,
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events_and_contexts=events_and_contexts,
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backfilled=backfilled,
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delete_existing=delete_existing,
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state_delta_for_room=state_delta_for_room,
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new_forward_extremeties=new_forward_extremeties,
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)
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persist_event_counter.inc(len(chunk))
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persist_event_counter.inc(len(events_and_contexts))
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if not backfilled:
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# backfilled events have negative stream orderings, so we don't
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# want to set the event_persisted_position to that.
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synapse.metrics.event_persisted_position.set(
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chunk[-1][0].internal_metadata.stream_ordering
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events_and_contexts[-1][0].internal_metadata.stream_ordering
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)
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for event, context in chunk:
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||||
for event, context in events_and_contexts:
|
||||
if context.app_service:
|
||||
origin_type = "local"
|
||||
origin_entity = context.app_service.id
|
||||
@ -569,58 +236,6 @@ class EventsStore(
|
||||
(room_id,), list(latest_event_ids)
|
||||
)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _calculate_new_extremities(self, room_id, event_contexts, latest_event_ids):
|
||||
"""Calculates the new forward extremities for a room given events to
|
||||
persist.
|
||||
|
||||
Assumes that we are only persisting events for one room at a time.
|
||||
"""
|
||||
|
||||
# we're only interested in new events which aren't outliers and which aren't
|
||||
# being rejected.
|
||||
new_events = [
|
||||
event
|
||||
for event, ctx in event_contexts
|
||||
if not event.internal_metadata.is_outlier()
|
||||
and not ctx.rejected
|
||||
and not event.internal_metadata.is_soft_failed()
|
||||
]
|
||||
|
||||
latest_event_ids = set(latest_event_ids)
|
||||
|
||||
# start with the existing forward extremities
|
||||
result = set(latest_event_ids)
|
||||
|
||||
# add all the new events to the list
|
||||
result.update(event.event_id for event in new_events)
|
||||
|
||||
# Now remove all events which are prev_events of any of the new events
|
||||
result.difference_update(
|
||||
e_id for event in new_events for e_id in event.prev_event_ids()
|
||||
)
|
||||
|
||||
# Remove any events which are prev_events of any existing events.
|
||||
existing_prevs = yield self._get_events_which_are_prevs(result)
|
||||
result.difference_update(existing_prevs)
|
||||
|
||||
# Finally handle the case where the new events have soft-failed prev
|
||||
# events. If they do we need to remove them and their prev events,
|
||||
# otherwise we end up with dangling extremities.
|
||||
existing_prevs = yield self._get_prevs_before_rejected(
|
||||
e_id for event in new_events for e_id in event.prev_event_ids()
|
||||
)
|
||||
result.difference_update(existing_prevs)
|
||||
|
||||
# We only update metrics for events that change forward extremities
|
||||
# (e.g. we ignore backfill/outliers/etc)
|
||||
if result != latest_event_ids:
|
||||
forward_extremities_counter.observe(len(result))
|
||||
stale = latest_event_ids & result
|
||||
stale_forward_extremities_counter.observe(len(stale))
|
||||
|
||||
return result
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _get_events_which_are_prevs(self, event_ids):
|
||||
"""Filter the supplied list of event_ids to get those which are prev_events of
|
||||
@ -725,188 +340,6 @@ class EventsStore(
|
||||
|
||||
return existing_prevs
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _get_new_state_after_events(
|
||||
self, room_id, events_context, old_latest_event_ids, new_latest_event_ids
|
||||
):
|
||||
"""Calculate the current state dict after adding some new events to
|
||||
a room
|
||||
|
||||
Args:
|
||||
room_id (str):
|
||||
room to which the events are being added. Used for logging etc
|
||||
|
||||
events_context (list[(EventBase, EventContext)]):
|
||||
events and contexts which are being added to the room
|
||||
|
||||
old_latest_event_ids (iterable[str]):
|
||||
the old forward extremities for the room.
|
||||
|
||||
new_latest_event_ids (iterable[str]):
|
||||
the new forward extremities for the room.
|
||||
|
||||
Returns:
|
||||
Deferred[tuple[dict[(str,str), str]|None, dict[(str,str), str]|None]]:
|
||||
Returns a tuple of two state maps, the first being the full new current
|
||||
state and the second being the delta to the existing current state.
|
||||
If both are None then there has been no change.
|
||||
|
||||
If there has been a change then we only return the delta if its
|
||||
already been calculated. Conversely if we do know the delta then
|
||||
the new current state is only returned if we've already calculated
|
||||
it.
|
||||
"""
|
||||
# map from state_group to ((type, key) -> event_id) state map
|
||||
state_groups_map = {}
|
||||
|
||||
# Map from (prev state group, new state group) -> delta state dict
|
||||
state_group_deltas = {}
|
||||
|
||||
for ev, ctx in events_context:
|
||||
if ctx.state_group is None:
|
||||
# This should only happen for outlier events.
|
||||
if not ev.internal_metadata.is_outlier():
|
||||
raise Exception(
|
||||
"Context for new event %s has no state "
|
||||
"group" % (ev.event_id,)
|
||||
)
|
||||
continue
|
||||
|
||||
if ctx.state_group in state_groups_map:
|
||||
continue
|
||||
|
||||
# We're only interested in pulling out state that has already
|
||||
# been cached in the context. We'll pull stuff out of the DB later
|
||||
# if necessary.
|
||||
current_state_ids = ctx.get_cached_current_state_ids()
|
||||
if current_state_ids is not None:
|
||||
state_groups_map[ctx.state_group] = current_state_ids
|
||||
|
||||
if ctx.prev_group:
|
||||
state_group_deltas[(ctx.prev_group, ctx.state_group)] = ctx.delta_ids
|
||||
|
||||
# We need to map the event_ids to their state groups. First, let's
|
||||
# check if the event is one we're persisting, in which case we can
|
||||
# pull the state group from its context.
|
||||
# Otherwise we need to pull the state group from the database.
|
||||
|
||||
# Set of events we need to fetch groups for. (We know none of the old
|
||||
# extremities are going to be in events_context).
|
||||
missing_event_ids = set(old_latest_event_ids)
|
||||
|
||||
event_id_to_state_group = {}
|
||||
for event_id in new_latest_event_ids:
|
||||
# First search in the list of new events we're adding.
|
||||
for ev, ctx in events_context:
|
||||
if event_id == ev.event_id and ctx.state_group is not None:
|
||||
event_id_to_state_group[event_id] = ctx.state_group
|
||||
break
|
||||
else:
|
||||
# If we couldn't find it, then we'll need to pull
|
||||
# the state from the database
|
||||
missing_event_ids.add(event_id)
|
||||
|
||||
if missing_event_ids:
|
||||
# Now pull out the state groups for any missing events from DB
|
||||
event_to_groups = yield self._get_state_group_for_events(missing_event_ids)
|
||||
event_id_to_state_group.update(event_to_groups)
|
||||
|
||||
# State groups of old_latest_event_ids
|
||||
old_state_groups = set(
|
||||
event_id_to_state_group[evid] for evid in old_latest_event_ids
|
||||
)
|
||||
|
||||
# State groups of new_latest_event_ids
|
||||
new_state_groups = set(
|
||||
event_id_to_state_group[evid] for evid in new_latest_event_ids
|
||||
)
|
||||
|
||||
# If they old and new groups are the same then we don't need to do
|
||||
# anything.
|
||||
if old_state_groups == new_state_groups:
|
||||
return None, None
|
||||
|
||||
if len(new_state_groups) == 1 and len(old_state_groups) == 1:
|
||||
# If we're going from one state group to another, lets check if
|
||||
# we have a delta for that transition. If we do then we can just
|
||||
# return that.
|
||||
|
||||
new_state_group = next(iter(new_state_groups))
|
||||
old_state_group = next(iter(old_state_groups))
|
||||
|
||||
delta_ids = state_group_deltas.get((old_state_group, new_state_group), None)
|
||||
if delta_ids is not None:
|
||||
# We have a delta from the existing to new current state,
|
||||
# so lets just return that. If we happen to already have
|
||||
# the current state in memory then lets also return that,
|
||||
# but it doesn't matter if we don't.
|
||||
new_state = state_groups_map.get(new_state_group)
|
||||
return new_state, delta_ids
|
||||
|
||||
# Now that we have calculated new_state_groups we need to get
|
||||
# their state IDs so we can resolve to a single state set.
|
||||
missing_state = new_state_groups - set(state_groups_map)
|
||||
if missing_state:
|
||||
group_to_state = yield self._get_state_for_groups(missing_state)
|
||||
state_groups_map.update(group_to_state)
|
||||
|
||||
if len(new_state_groups) == 1:
|
||||
# If there is only one state group, then we know what the current
|
||||
# state is.
|
||||
return state_groups_map[new_state_groups.pop()], None
|
||||
|
||||
# Ok, we need to defer to the state handler to resolve our state sets.
|
||||
|
||||
state_groups = {sg: state_groups_map[sg] for sg in new_state_groups}
|
||||
|
||||
events_map = {ev.event_id: ev for ev, _ in events_context}
|
||||
|
||||
# We need to get the room version, which is in the create event.
|
||||
# Normally that'd be in the database, but its also possible that we're
|
||||
# currently trying to persist it.
|
||||
room_version = None
|
||||
for ev, _ in events_context:
|
||||
if ev.type == EventTypes.Create and ev.state_key == "":
|
||||
room_version = ev.content.get("room_version", "1")
|
||||
break
|
||||
|
||||
if not room_version:
|
||||
room_version = yield self.get_room_version(room_id)
|
||||
|
||||
logger.debug("calling resolve_state_groups from preserve_events")
|
||||
res = yield self._state_resolution_handler.resolve_state_groups(
|
||||
room_id,
|
||||
room_version,
|
||||
state_groups,
|
||||
events_map,
|
||||
state_res_store=StateResolutionStore(self),
|
||||
)
|
||||
|
||||
return res.state, None
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _calculate_state_delta(self, room_id, current_state):
|
||||
"""Calculate the new state deltas for a room.
|
||||
|
||||
Assumes that we are only persisting events for one room at a time.
|
||||
|
||||
Returns:
|
||||
tuple[list, dict] (to_delete, to_insert): where to_delete are the
|
||||
type/state_keys to remove from current_state_events and `to_insert`
|
||||
are the updates to current_state_events.
|
||||
"""
|
||||
existing_state = yield self.get_current_state_ids(room_id)
|
||||
|
||||
to_delete = [key for key in existing_state if key not in current_state]
|
||||
|
||||
to_insert = {
|
||||
key: ev_id
|
||||
for key, ev_id in iteritems(current_state)
|
||||
if ev_id != existing_state.get(key)
|
||||
}
|
||||
|
||||
return to_delete, to_insert
|
||||
|
||||
@log_function
|
||||
def _persist_events_txn(
|
||||
self,
|
||||
|
644
synapse/storage/persist_events.py
Normal file
644
synapse/storage/persist_events.py
Normal file
@ -0,0 +1,644 @@
|
||||
# -*- coding: utf-8 -*-
|
||||
# Copyright 2014-2016 OpenMarket Ltd
|
||||
# Copyright 2018-2019 New Vector Ltd
|
||||
# Copyright 2019 The Matrix.org Foundation C.I.C.
|
||||
#
|
||||
# Licensed under the Apache License, Version 2.0 (the "License");
|
||||
# you may not use this file except in compliance with the License.
|
||||
# You may obtain a copy of the License at
|
||||
#
|
||||
# http://www.apache.org/licenses/LICENSE-2.0
|
||||
#
|
||||
# Unless required by applicable law or agreed to in writing, software
|
||||
# distributed under the License is distributed on an "AS IS" BASIS,
|
||||
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
# See the License for the specific language governing permissions and
|
||||
# limitations under the License.
|
||||
|
||||
import logging
|
||||
from collections import deque, namedtuple
|
||||
|
||||
from six import iteritems
|
||||
from six.moves import range
|
||||
|
||||
from prometheus_client import Counter, Histogram
|
||||
|
||||
from twisted.internet import defer
|
||||
|
||||
from synapse.api.constants import EventTypes
|
||||
from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
|
||||
from synapse.metrics.background_process_metrics import run_as_background_process
|
||||
from synapse.state import StateResolutionStore
|
||||
from synapse.util.async_helpers import ObservableDeferred
|
||||
from synapse.util.metrics import Measure
|
||||
|
||||
logger = logging.getLogger(__name__)
|
||||
|
||||
# The number of times we are recalculating the current state
|
||||
state_delta_counter = Counter("synapse_storage_events_state_delta", "")
|
||||
|
||||
# The number of times we are recalculating state when there is only a
|
||||
# single forward extremity
|
||||
state_delta_single_event_counter = Counter(
|
||||
"synapse_storage_events_state_delta_single_event", ""
|
||||
)
|
||||
|
||||
# The number of times we are reculating state when we could have resonably
|
||||
# calculated the delta when we calculated the state for an event we were
|
||||
# persisting.
|
||||
state_delta_reuse_delta_counter = Counter(
|
||||
"synapse_storage_events_state_delta_reuse_delta", ""
|
||||
)
|
||||
|
||||
# The number of forward extremities for each new event.
|
||||
forward_extremities_counter = Histogram(
|
||||
"synapse_storage_events_forward_extremities_persisted",
|
||||
"Number of forward extremities for each new event",
|
||||
buckets=(1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"),
|
||||
)
|
||||
|
||||
# The number of stale forward extremities for each new event. Stale extremities
|
||||
# are those that were in the previous set of extremities as well as the new.
|
||||
stale_forward_extremities_counter = Histogram(
|
||||
"synapse_storage_events_stale_forward_extremities_persisted",
|
||||
"Number of unchanged forward extremities for each new event",
|
||||
buckets=(0, 1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"),
|
||||
)
|
||||
|
||||
|
||||
class _EventPeristenceQueue(object):
|
||||
"""Queues up events so that they can be persisted in bulk with only one
|
||||
concurrent transaction per room.
|
||||
"""
|
||||
|
||||
_EventPersistQueueItem = namedtuple(
|
||||
"_EventPersistQueueItem", ("events_and_contexts", "backfilled", "deferred")
|
||||
)
|
||||
|
||||
def __init__(self):
|
||||
self._event_persist_queues = {}
|
||||
self._currently_persisting_rooms = set()
|
||||
|
||||
def add_to_queue(self, room_id, events_and_contexts, backfilled):
|
||||
"""Add events to the queue, with the given persist_event options.
|
||||
|
||||
NB: due to the normal usage pattern of this method, it does *not*
|
||||
follow the synapse logcontext rules, and leaves the logcontext in
|
||||
place whether or not the returned deferred is ready.
|
||||
|
||||
Args:
|
||||
room_id (str):
|
||||
events_and_contexts (list[(EventBase, EventContext)]):
|
||||
backfilled (bool):
|
||||
|
||||
Returns:
|
||||
defer.Deferred: a deferred which will resolve once the events are
|
||||
persisted. Runs its callbacks *without* a logcontext.
|
||||
"""
|
||||
queue = self._event_persist_queues.setdefault(room_id, deque())
|
||||
if queue:
|
||||
# if the last item in the queue has the same `backfilled` setting,
|
||||
# we can just add these new events to that item.
|
||||
end_item = queue[-1]
|
||||
if end_item.backfilled == backfilled:
|
||||
end_item.events_and_contexts.extend(events_and_contexts)
|
||||
return end_item.deferred.observe()
|
||||
|
||||
deferred = ObservableDeferred(defer.Deferred(), consumeErrors=True)
|
||||
|
||||
queue.append(
|
||||
self._EventPersistQueueItem(
|
||||
events_and_contexts=events_and_contexts,
|
||||
backfilled=backfilled,
|
||||
deferred=deferred,
|
||||
)
|
||||
)
|
||||
|
||||
return deferred.observe()
|
||||
|
||||
def handle_queue(self, room_id, per_item_callback):
|
||||
"""Attempts to handle the queue for a room if not already being handled.
|
||||
|
||||
The given callback will be invoked with for each item in the queue,
|
||||
of type _EventPersistQueueItem. The per_item_callback will continuously
|
||||
be called with new items, unless the queue becomnes empty. The return
|
||||
value of the function will be given to the deferreds waiting on the item,
|
||||
exceptions will be passed to the deferreds as well.
|
||||
|
||||
This function should therefore be called whenever anything is added
|
||||
to the queue.
|
||||
|
||||
If another callback is currently handling the queue then it will not be
|
||||
invoked.
|
||||
"""
|
||||
|
||||
if room_id in self._currently_persisting_rooms:
|
||||
return
|
||||
|
||||
self._currently_persisting_rooms.add(room_id)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def handle_queue_loop():
|
||||
try:
|
||||
queue = self._get_drainining_queue(room_id)
|
||||
for item in queue:
|
||||
try:
|
||||
ret = yield per_item_callback(item)
|
||||
except Exception:
|
||||
with PreserveLoggingContext():
|
||||
item.deferred.errback()
|
||||
else:
|
||||
with PreserveLoggingContext():
|
||||
item.deferred.callback(ret)
|
||||
finally:
|
||||
queue = self._event_persist_queues.pop(room_id, None)
|
||||
if queue:
|
||||
self._event_persist_queues[room_id] = queue
|
||||
self._currently_persisting_rooms.discard(room_id)
|
||||
|
||||
# set handle_queue_loop off in the background
|
||||
run_as_background_process("persist_events", handle_queue_loop)
|
||||
|
||||
def _get_drainining_queue(self, room_id):
|
||||
queue = self._event_persist_queues.setdefault(room_id, deque())
|
||||
|
||||
try:
|
||||
while True:
|
||||
yield queue.popleft()
|
||||
except IndexError:
|
||||
# Queue has been drained.
|
||||
pass
|
||||
|
||||
|
||||
class EventsPersistenceStore(object):
|
||||
def __init__(self, hs):
|
||||
# We ultimately want to split out the state store from the main store,
|
||||
# so we use separate variables here even though they point to the same
|
||||
# store for now.
|
||||
self.main_store = hs.get_datastore()
|
||||
self.state_store = hs.get_datastore()
|
||||
|
||||
self._clock = hs.get_clock()
|
||||
self.is_mine_id = hs.is_mine_id
|
||||
self._event_persist_queue = _EventPeristenceQueue()
|
||||
self._state_resolution_handler = hs.get_state_resolution_handler()
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def persist_events(self, events_and_contexts, backfilled=False):
|
||||
"""
|
||||
Write events to the database
|
||||
Args:
|
||||
events_and_contexts: list of tuples of (event, context)
|
||||
backfilled (bool): Whether the results are retrieved from federation
|
||||
via backfill or not. Used to determine if they're "new" events
|
||||
which might update the current state etc.
|
||||
|
||||
Returns:
|
||||
Deferred[int]: the stream ordering of the latest persisted event
|
||||
"""
|
||||
partitioned = {}
|
||||
for event, ctx in events_and_contexts:
|
||||
partitioned.setdefault(event.room_id, []).append((event, ctx))
|
||||
|
||||
deferreds = []
|
||||
for room_id, evs_ctxs in iteritems(partitioned):
|
||||
d = self._event_persist_queue.add_to_queue(
|
||||
room_id, evs_ctxs, backfilled=backfilled
|
||||
)
|
||||
deferreds.append(d)
|
||||
|
||||
for room_id in partitioned:
|
||||
self._maybe_start_persisting(room_id)
|
||||
|
||||
yield make_deferred_yieldable(
|
||||
defer.gatherResults(deferreds, consumeErrors=True)
|
||||
)
|
||||
|
||||
max_persisted_id = yield self.main_store.get_current_events_token()
|
||||
|
||||
return max_persisted_id
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def persist_event(self, event, context, backfilled=False):
|
||||
"""
|
||||
|
||||
Args:
|
||||
event (EventBase):
|
||||
context (EventContext):
|
||||
backfilled (bool):
|
||||
|
||||
Returns:
|
||||
Deferred: resolves to (int, int): the stream ordering of ``event``,
|
||||
and the stream ordering of the latest persisted event
|
||||
"""
|
||||
deferred = self._event_persist_queue.add_to_queue(
|
||||
event.room_id, [(event, context)], backfilled=backfilled
|
||||
)
|
||||
|
||||
self._maybe_start_persisting(event.room_id)
|
||||
|
||||
yield make_deferred_yieldable(deferred)
|
||||
|
||||
max_persisted_id = yield self.main_store.get_current_events_token()
|
||||
return (event.internal_metadata.stream_ordering, max_persisted_id)
|
||||
|
||||
def _maybe_start_persisting(self, room_id):
|
||||
@defer.inlineCallbacks
|
||||
def persisting_queue(item):
|
||||
with Measure(self._clock, "persist_events"):
|
||||
yield self._persist_events(
|
||||
item.events_and_contexts, backfilled=item.backfilled
|
||||
)
|
||||
|
||||
self._event_persist_queue.handle_queue(room_id, persisting_queue)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _persist_events(
|
||||
self, events_and_contexts, backfilled=False, delete_existing=False
|
||||
):
|
||||
"""Persist events to db
|
||||
|
||||
Args:
|
||||
events_and_contexts (list[(EventBase, EventContext)]):
|
||||
backfilled (bool):
|
||||
delete_existing (bool):
|
||||
|
||||
Returns:
|
||||
Deferred: resolves when the events have been persisted
|
||||
"""
|
||||
if not events_and_contexts:
|
||||
return
|
||||
|
||||
chunks = [
|
||||
events_and_contexts[x : x + 100]
|
||||
for x in range(0, len(events_and_contexts), 100)
|
||||
]
|
||||
|
||||
for chunk in chunks:
|
||||
# We can't easily parallelize these since different chunks
|
||||
# might contain the same event. :(
|
||||
|
||||
# NB: Assumes that we are only persisting events for one room
|
||||
# at a time.
|
||||
|
||||
# map room_id->list[event_ids] giving the new forward
|
||||
# extremities in each room
|
||||
new_forward_extremeties = {}
|
||||
|
||||
# map room_id->(type,state_key)->event_id tracking the full
|
||||
# state in each room after adding these events.
|
||||
# This is simply used to prefill the get_current_state_ids
|
||||
# cache
|
||||
current_state_for_room = {}
|
||||
|
||||
# map room_id->(to_delete, to_insert) where to_delete is a list
|
||||
# of type/state keys to remove from current state, and to_insert
|
||||
# is a map (type,key)->event_id giving the state delta in each
|
||||
# room
|
||||
state_delta_for_room = {}
|
||||
|
||||
if not backfilled:
|
||||
with Measure(self._clock, "_calculate_state_and_extrem"):
|
||||
# Work out the new "current state" for each room.
|
||||
# We do this by working out what the new extremities are and then
|
||||
# calculating the state from that.
|
||||
events_by_room = {}
|
||||
for event, context in chunk:
|
||||
events_by_room.setdefault(event.room_id, []).append(
|
||||
(event, context)
|
||||
)
|
||||
|
||||
for room_id, ev_ctx_rm in iteritems(events_by_room):
|
||||
latest_event_ids = yield self.main_store.get_latest_event_ids_in_room(
|
||||
room_id
|
||||
)
|
||||
new_latest_event_ids = yield self._calculate_new_extremities(
|
||||
room_id, ev_ctx_rm, latest_event_ids
|
||||
)
|
||||
|
||||
latest_event_ids = set(latest_event_ids)
|
||||
if new_latest_event_ids == latest_event_ids:
|
||||
# No change in extremities, so no change in state
|
||||
continue
|
||||
|
||||
# there should always be at least one forward extremity.
|
||||
# (except during the initial persistence of the send_join
|
||||
# results, in which case there will be no existing
|
||||
# extremities, so we'll `continue` above and skip this bit.)
|
||||
assert new_latest_event_ids, "No forward extremities left!"
|
||||
|
||||
new_forward_extremeties[room_id] = new_latest_event_ids
|
||||
|
||||
len_1 = (
|
||||
len(latest_event_ids) == 1
|
||||
and len(new_latest_event_ids) == 1
|
||||
)
|
||||
if len_1:
|
||||
all_single_prev_not_state = all(
|
||||
len(event.prev_event_ids()) == 1
|
||||
and not event.is_state()
|
||||
for event, ctx in ev_ctx_rm
|
||||
)
|
||||
# Don't bother calculating state if they're just
|
||||
# a long chain of single ancestor non-state events.
|
||||
if all_single_prev_not_state:
|
||||
continue
|
||||
|
||||
state_delta_counter.inc()
|
||||
if len(new_latest_event_ids) == 1:
|
||||
state_delta_single_event_counter.inc()
|
||||
|
||||
# This is a fairly handwavey check to see if we could
|
||||
# have guessed what the delta would have been when
|
||||
# processing one of these events.
|
||||
# What we're interested in is if the latest extremities
|
||||
# were the same when we created the event as they are
|
||||
# now. When this server creates a new event (as opposed
|
||||
# to receiving it over federation) it will use the
|
||||
# forward extremities as the prev_events, so we can
|
||||
# guess this by looking at the prev_events and checking
|
||||
# if they match the current forward extremities.
|
||||
for ev, _ in ev_ctx_rm:
|
||||
prev_event_ids = set(ev.prev_event_ids())
|
||||
if latest_event_ids == prev_event_ids:
|
||||
state_delta_reuse_delta_counter.inc()
|
||||
break
|
||||
|
||||
logger.info("Calculating state delta for room %s", room_id)
|
||||
with Measure(
|
||||
self._clock, "persist_events.get_new_state_after_events"
|
||||
):
|
||||
res = yield self._get_new_state_after_events(
|
||||
room_id,
|
||||
ev_ctx_rm,
|
||||
latest_event_ids,
|
||||
new_latest_event_ids,
|
||||
)
|
||||
current_state, delta_ids = res
|
||||
|
||||
# If either are not None then there has been a change,
|
||||
# and we need to work out the delta (or use that
|
||||
# given)
|
||||
if delta_ids is not None:
|
||||
# If there is a delta we know that we've
|
||||
# only added or replaced state, never
|
||||
# removed keys entirely.
|
||||
state_delta_for_room[room_id] = ([], delta_ids)
|
||||
elif current_state is not None:
|
||||
with Measure(
|
||||
self._clock, "persist_events.calculate_state_delta"
|
||||
):
|
||||
delta = yield self._calculate_state_delta(
|
||||
room_id, current_state
|
||||
)
|
||||
state_delta_for_room[room_id] = delta
|
||||
|
||||
# If we have the current_state then lets prefill
|
||||
# the cache with it.
|
||||
if current_state is not None:
|
||||
current_state_for_room[room_id] = current_state
|
||||
|
||||
yield self.main_store._persist_events(
|
||||
chunk,
|
||||
current_state_for_room=current_state_for_room,
|
||||
state_delta_for_room=state_delta_for_room,
|
||||
new_forward_extremeties=new_forward_extremeties,
|
||||
backfilled=backfilled,
|
||||
delete_existing=delete_existing,
|
||||
)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _calculate_new_extremities(self, room_id, event_contexts, latest_event_ids):
|
||||
"""Calculates the new forward extremities for a room given events to
|
||||
persist.
|
||||
|
||||
Assumes that we are only persisting events for one room at a time.
|
||||
"""
|
||||
|
||||
# we're only interested in new events which aren't outliers and which aren't
|
||||
# being rejected.
|
||||
new_events = [
|
||||
event
|
||||
for event, ctx in event_contexts
|
||||
if not event.internal_metadata.is_outlier()
|
||||
and not ctx.rejected
|
||||
and not event.internal_metadata.is_soft_failed()
|
||||
]
|
||||
|
||||
latest_event_ids = set(latest_event_ids)
|
||||
|
||||
# start with the existing forward extremities
|
||||
result = set(latest_event_ids)
|
||||
|
||||
# add all the new events to the list
|
||||
result.update(event.event_id for event in new_events)
|
||||
|
||||
# Now remove all events which are prev_events of any of the new events
|
||||
result.difference_update(
|
||||
e_id for event in new_events for e_id in event.prev_event_ids()
|
||||
)
|
||||
|
||||
# Remove any events which are prev_events of any existing events.
|
||||
existing_prevs = yield self.main_store._get_events_which_are_prevs(result)
|
||||
result.difference_update(existing_prevs)
|
||||
|
||||
# Finally handle the case where the new events have soft-failed prev
|
||||
# events. If they do we need to remove them and their prev events,
|
||||
# otherwise we end up with dangling extremities.
|
||||
existing_prevs = yield self.main_store._get_prevs_before_rejected(
|
||||
e_id for event in new_events for e_id in event.prev_event_ids()
|
||||
)
|
||||
result.difference_update(existing_prevs)
|
||||
|
||||
# We only update metrics for events that change forward extremities
|
||||
# (e.g. we ignore backfill/outliers/etc)
|
||||
if result != latest_event_ids:
|
||||
forward_extremities_counter.observe(len(result))
|
||||
stale = latest_event_ids & result
|
||||
stale_forward_extremities_counter.observe(len(stale))
|
||||
|
||||
return result
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _get_new_state_after_events(
|
||||
self, room_id, events_context, old_latest_event_ids, new_latest_event_ids
|
||||
):
|
||||
"""Calculate the current state dict after adding some new events to
|
||||
a room
|
||||
|
||||
Args:
|
||||
room_id (str):
|
||||
room to which the events are being added. Used for logging etc
|
||||
|
||||
events_context (list[(EventBase, EventContext)]):
|
||||
events and contexts which are being added to the room
|
||||
|
||||
old_latest_event_ids (iterable[str]):
|
||||
the old forward extremities for the room.
|
||||
|
||||
new_latest_event_ids (iterable[str]):
|
||||
the new forward extremities for the room.
|
||||
|
||||
Returns:
|
||||
Deferred[tuple[dict[(str,str), str]|None, dict[(str,str), str]|None]]:
|
||||
Returns a tuple of two state maps, the first being the full new current
|
||||
state and the second being the delta to the existing current state.
|
||||
If both are None then there has been no change.
|
||||
|
||||
If there has been a change then we only return the delta if its
|
||||
already been calculated. Conversely if we do know the delta then
|
||||
the new current state is only returned if we've already calculated
|
||||
it.
|
||||
"""
|
||||
# map from state_group to ((type, key) -> event_id) state map
|
||||
state_groups_map = {}
|
||||
|
||||
# Map from (prev state group, new state group) -> delta state dict
|
||||
state_group_deltas = {}
|
||||
|
||||
for ev, ctx in events_context:
|
||||
if ctx.state_group is None:
|
||||
# This should only happen for outlier events.
|
||||
if not ev.internal_metadata.is_outlier():
|
||||
raise Exception(
|
||||
"Context for new event %s has no state "
|
||||
"group" % (ev.event_id,)
|
||||
)
|
||||
continue
|
||||
|
||||
if ctx.state_group in state_groups_map:
|
||||
continue
|
||||
|
||||
# We're only interested in pulling out state that has already
|
||||
# been cached in the context. We'll pull stuff out of the DB later
|
||||
# if necessary.
|
||||
current_state_ids = ctx.get_cached_current_state_ids()
|
||||
if current_state_ids is not None:
|
||||
state_groups_map[ctx.state_group] = current_state_ids
|
||||
|
||||
if ctx.prev_group:
|
||||
state_group_deltas[(ctx.prev_group, ctx.state_group)] = ctx.delta_ids
|
||||
|
||||
# We need to map the event_ids to their state groups. First, let's
|
||||
# check if the event is one we're persisting, in which case we can
|
||||
# pull the state group from its context.
|
||||
# Otherwise we need to pull the state group from the database.
|
||||
|
||||
# Set of events we need to fetch groups for. (We know none of the old
|
||||
# extremities are going to be in events_context).
|
||||
missing_event_ids = set(old_latest_event_ids)
|
||||
|
||||
event_id_to_state_group = {}
|
||||
for event_id in new_latest_event_ids:
|
||||
# First search in the list of new events we're adding.
|
||||
for ev, ctx in events_context:
|
||||
if event_id == ev.event_id and ctx.state_group is not None:
|
||||
event_id_to_state_group[event_id] = ctx.state_group
|
||||
break
|
||||
else:
|
||||
# If we couldn't find it, then we'll need to pull
|
||||
# the state from the database
|
||||
missing_event_ids.add(event_id)
|
||||
|
||||
if missing_event_ids:
|
||||
# Now pull out the state groups for any missing events from DB
|
||||
event_to_groups = yield self.state_store._get_state_group_for_events(
|
||||
missing_event_ids
|
||||
)
|
||||
event_id_to_state_group.update(event_to_groups)
|
||||
|
||||
# State groups of old_latest_event_ids
|
||||
old_state_groups = set(
|
||||
event_id_to_state_group[evid] for evid in old_latest_event_ids
|
||||
)
|
||||
|
||||
# State groups of new_latest_event_ids
|
||||
new_state_groups = set(
|
||||
event_id_to_state_group[evid] for evid in new_latest_event_ids
|
||||
)
|
||||
|
||||
# If they old and new groups are the same then we don't need to do
|
||||
# anything.
|
||||
if old_state_groups == new_state_groups:
|
||||
return None, None
|
||||
|
||||
if len(new_state_groups) == 1 and len(old_state_groups) == 1:
|
||||
# If we're going from one state group to another, lets check if
|
||||
# we have a delta for that transition. If we do then we can just
|
||||
# return that.
|
||||
|
||||
new_state_group = next(iter(new_state_groups))
|
||||
old_state_group = next(iter(old_state_groups))
|
||||
|
||||
delta_ids = state_group_deltas.get((old_state_group, new_state_group), None)
|
||||
if delta_ids is not None:
|
||||
# We have a delta from the existing to new current state,
|
||||
# so lets just return that. If we happen to already have
|
||||
# the current state in memory then lets also return that,
|
||||
# but it doesn't matter if we don't.
|
||||
new_state = state_groups_map.get(new_state_group)
|
||||
return new_state, delta_ids
|
||||
|
||||
# Now that we have calculated new_state_groups we need to get
|
||||
# their state IDs so we can resolve to a single state set.
|
||||
missing_state = new_state_groups - set(state_groups_map)
|
||||
if missing_state:
|
||||
group_to_state = yield self.state_store._get_state_for_groups(missing_state)
|
||||
state_groups_map.update(group_to_state)
|
||||
|
||||
if len(new_state_groups) == 1:
|
||||
# If there is only one state group, then we know what the current
|
||||
# state is.
|
||||
return state_groups_map[new_state_groups.pop()], None
|
||||
|
||||
# Ok, we need to defer to the state handler to resolve our state sets.
|
||||
|
||||
state_groups = {sg: state_groups_map[sg] for sg in new_state_groups}
|
||||
|
||||
events_map = {ev.event_id: ev for ev, _ in events_context}
|
||||
|
||||
# We need to get the room version, which is in the create event.
|
||||
# Normally that'd be in the database, but its also possible that we're
|
||||
# currently trying to persist it.
|
||||
room_version = None
|
||||
for ev, _ in events_context:
|
||||
if ev.type == EventTypes.Create and ev.state_key == "":
|
||||
room_version = ev.content.get("room_version", "1")
|
||||
break
|
||||
|
||||
if not room_version:
|
||||
room_version = yield self.main_store.get_room_version(room_id)
|
||||
|
||||
logger.debug("calling resolve_state_groups from preserve_events")
|
||||
res = yield self._state_resolution_handler.resolve_state_groups(
|
||||
room_id,
|
||||
room_version,
|
||||
state_groups,
|
||||
events_map,
|
||||
state_res_store=StateResolutionStore(self.main_store),
|
||||
)
|
||||
|
||||
return res.state, None
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def _calculate_state_delta(self, room_id, current_state):
|
||||
"""Calculate the new state deltas for a room.
|
||||
|
||||
Assumes that we are only persisting events for one room at a time.
|
||||
|
||||
Returns:
|
||||
tuple[list, dict] (to_delete, to_insert): where to_delete are the
|
||||
type/state_keys to remove from current_state_events and `to_insert`
|
||||
are the updates to current_state_events.
|
||||
"""
|
||||
existing_state = yield self.main_store.get_current_state_ids(room_id)
|
||||
|
||||
to_delete = [key for key in existing_state if key not in current_state]
|
||||
|
||||
to_insert = {
|
||||
key: ev_id
|
||||
for key, ev_id in iteritems(current_state)
|
||||
if ev_id != existing_state.get(key)
|
||||
}
|
||||
|
||||
return to_delete, to_insert
|
Loading…
Reference in New Issue
Block a user