Merge pull request #193 from matrix-org/erikj/bulk_persist_event

Add bulk insert events API

7 files changed, 503 insertions, 376 deletions

diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index d7f197f247..f7155fd8d3 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -140,26 +140,29 @@ class FederationHandler(BaseHandler):
         if state and auth_chain is not None:
             # If we have any state or auth_chain given to us by the replication
             # layer, then we should handle them (if we haven't before.)
+
+            event_infos = []
+
             for e in itertools.chain(auth_chain, state):
                 if e.event_id in seen_ids:
                     continue
-
                 e.internal_metadata.outlier = True
-                try:
-                    auth_ids = [e_id for e_id, _ in e.auth_events]
-                    auth = {
-                        (e.type, e.state_key): e for e in auth_chain
-                        if e.event_id in auth_ids
-                    }
-                    yield self._handle_new_event(
-                        origin, e, auth_events=auth
-                    )
-                    seen_ids.add(e.event_id)
-                except:
-                    logger.exception(
-                        "Failed to handle state event %s",
-                        e.event_id,
-                    )
+                auth_ids = [e_id for e_id, _ in e.auth_events]
+                auth = {
+                    (e.type, e.state_key): e for e in auth_chain
+                    if e.event_id in auth_ids
+                }
+                event_infos.append({
+                    "event": e,
+                    "auth_events": auth,
+                })
+                seen_ids.add(e.event_id)
+
+            yield self._handle_new_events(
+                origin,
+                event_infos,
+                outliers=True
+            )
 
         try:
             _, event_stream_id, max_stream_id = yield self._handle_new_event(
@@ -344,38 +347,29 @@ class FederationHandler(BaseHandler):
         ).addErrback(unwrapFirstError)
         auth_events.update({a.event_id: a for a in results})
 
-        yield defer.gatherResults(
-            [
-                self._handle_new_event(
-                    dest, a,
-                    auth_events={
-                        (auth_events[a_id].type, auth_events[a_id].state_key):
-                        auth_events[a_id]
-                        for a_id, _ in a.auth_events
-                    },
-                )
-                for a in auth_events.values()
-                if a.event_id not in seen_events
-            ],
-            consumeErrors=True,
-        ).addErrback(unwrapFirstError)
-
-        yield defer.gatherResults(
-            [
-                self._handle_new_event(
-                    dest, event_map[e_id],
-                    state=events_to_state[e_id],
-                    backfilled=True,
-                    auth_events={
-                        (auth_events[a_id].type, auth_events[a_id].state_key):
-                        auth_events[a_id]
-                        for a_id, _ in event_map[e_id].auth_events
-                    },
-                )
-                for e_id in events_to_state
-            ],
-            consumeErrors=True
-        ).addErrback(unwrapFirstError)
+        ev_infos = []
+        for a in auth_events.values():
+            if a.event_id in seen_events:
+                continue
+            ev_infos.append({
+                "event": a,
+                "auth_events": {
+                    (auth_events[a_id].type, auth_events[a_id].state_key):
+                    auth_events[a_id]
+                    for a_id, _ in a.auth_events
+                }
+            })
+
+        for e_id in events_to_state:
+            ev_infos.append({
+                "event": event_map[e_id],
+                "state": events_to_state[e_id],
+                "auth_events": {
+                    (auth_events[a_id].type, auth_events[a_id].state_key):
+                    auth_events[a_id]
+                    for a_id, _ in event_map[e_id].auth_events
+                }
+            })
 
         events.sort(key=lambda e: e.depth)
 
@@ -383,10 +377,14 @@ class FederationHandler(BaseHandler):
             if event in events_to_state:
                 continue
 
-            yield self._handle_new_event(
-                dest, event,
-                backfilled=True,
-            )
+            ev_infos.append({
+                "event": event,
+            })
+
+        yield self._handle_new_events(
+            dest, ev_infos,
+            backfilled=True,
+        )
 
         defer.returnValue(events)
 
@@ -652,32 +650,22 @@ class FederationHandler(BaseHandler):
                 # FIXME
                 pass
 
-            yield self._handle_auth_events(
-                origin, [e for e in auth_chain if e.event_id != event.event_id]
-            )
-
-            @defer.inlineCallbacks
-            def handle_state(e):
+            ev_infos = []
+            for e in itertools.chain(state, auth_chain):
                 if e.event_id == event.event_id:
-                    return
+                    continue
 
                 e.internal_metadata.outlier = True
-                try:
-                    auth_ids = [e_id for e_id, _ in e.auth_events]
-                    auth = {
+                auth_ids = [e_id for e_id, _ in e.auth_events]
+                ev_infos.append({
+                    "event": e,
+                    "auth_events": {
                         (e.type, e.state_key): e for e in auth_chain
                         if e.event_id in auth_ids
                     }
-                    yield self._handle_new_event(
-                        origin, e, auth_events=auth
-                    )
-                except:
-                    logger.exception(
-                        "Failed to handle state event %s",
-                        e.event_id,
-                    )
+                })
 
-            yield defer.DeferredList([handle_state(e) for e in state])
+            yield self._handle_new_events(origin, ev_infos, outliers=True)
 
             auth_ids = [e_id for e_id, _ in event.auth_events]
             auth_events = {
@@ -994,11 +982,54 @@ class FederationHandler(BaseHandler):
     def _handle_new_event(self, origin, event, state=None, backfilled=False,
                           current_state=None, auth_events=None):
 
-        logger.debug(
-            "_handle_new_event: %s, sigs: %s",
-            event.event_id, event.signatures,
+        outlier = event.internal_metadata.is_outlier()
+
+        context = yield self._prep_event(
+            origin, event,
+            state=state,
+            backfilled=backfilled,
+            current_state=current_state,
+            auth_events=auth_events,
         )
 
+        event_stream_id, max_stream_id = yield self.store.persist_event(
+            event,
+            context=context,
+            backfilled=backfilled,
+            is_new_state=(not outlier and not backfilled),
+            current_state=current_state,
+        )
+
+        defer.returnValue((context, event_stream_id, max_stream_id))
+
+    @defer.inlineCallbacks
+    def _handle_new_events(self, origin, event_infos, backfilled=False,
+                           outliers=False):
+        contexts = yield defer.gatherResults(
+            [
+                self._prep_event(
+                    origin,
+                    ev_info["event"],
+                    state=ev_info.get("state"),
+                    backfilled=backfilled,
+                    auth_events=ev_info.get("auth_events"),
+                )
+                for ev_info in event_infos
+            ]
+        )
+
+        yield self.store.persist_events(
+            [
+                (ev_info["event"], context)
+                for ev_info, context in itertools.izip(event_infos, contexts)
+            ],
+            backfilled=backfilled,
+            is_new_state=(not outliers and not backfilled),
+        )
+
+    @defer.inlineCallbacks
+    def _prep_event(self, origin, event, state=None, backfilled=False,
+                    current_state=None, auth_events=None):
         outlier = event.internal_metadata.is_outlier()
 
         context = yield self.state_handler.compute_event_context(
@@ -1008,13 +1039,6 @@ class FederationHandler(BaseHandler):
         if not auth_events:
             auth_events = context.current_state
 
-        logger.debug(
-            "_handle_new_event: %s, auth_events: %s",
-            event.event_id, auth_events,
-        )
-
-        is_new_state = not outlier
-
         # This is a hack to fix some old rooms where the initial join event
         # didn't reference the create event in its auth events.
         if event.type == EventTypes.Member and not event.auth_events:
@@ -1038,26 +1062,7 @@ class FederationHandler(BaseHandler):
 
             context.rejected = RejectedReason.AUTH_ERROR
 
-            # FIXME: Don't store as rejected with AUTH_ERROR if we haven't
-            # seen all the auth events.
-            yield self.store.persist_event(
-                event,
-                context=context,
-                backfilled=backfilled,
-                is_new_state=False,
-                current_state=current_state,
-            )
-            raise
-
-        event_stream_id, max_stream_id = yield self.store.persist_event(
-            event,
-            context=context,
-            backfilled=backfilled,
-            is_new_state=(is_new_state and not backfilled),
-            current_state=current_state,
-        )
-
-        defer.returnValue((context, event_stream_id, max_stream_id))
+        defer.returnValue(context)
 
     @defer.inlineCallbacks
     def on_query_auth(self, origin, event_id, remote_auth_chain, rejects,
@@ -1120,14 +1125,24 @@ class FederationHandler(BaseHandler):
     @log_function
     def do_auth(self, origin, event, context, auth_events):
         # Check if we have all the auth events.
-        have_events = yield self.store.have_events(
-            [e_id for e_id, _ in event.auth_events]
-        )
-
+        current_state = set(e.event_id for e in auth_events.values())
         event_auth_events = set(e_id for e_id, _ in event.auth_events)
+
+        if event_auth_events - current_state:
+            have_events = yield self.store.have_events(
+                event_auth_events - current_state
+            )
+        else:
+            have_events = {}
+
+        have_events.update({
+            e.event_id: ""
+            for e in auth_events.values()
+        })
+
         seen_events = set(have_events.keys())
 
-        missing_auth = event_auth_events - seen_events
+        missing_auth = event_auth_events - seen_events - current_state
 
         if missing_auth:
             logger.info("Missing auth: %s", missing_auth)
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index c71019d93b..45b86c94e8 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -282,8 +282,7 @@ class EventFederationStore(SQLBaseStore):
                 },
             )
 
-    def _handle_prev_events(self, txn, outlier, event_id, prev_events,
-                            room_id):
+    def _handle_mult_prev_events(self, txn, events):
         """
         For the given event, update the event edges table and forward and
         backward extremities tables.
@@ -293,68 +292,75 @@ class EventFederationStore(SQLBaseStore):
             table="event_edges",
             values=[
                 {
-                    "event_id": event_id,
+                    "event_id": ev.event_id,
                     "prev_event_id": e_id,
-                    "room_id": room_id,
+                    "room_id": ev.room_id,
                     "is_state": False,
                 }
-                for e_id, _ in prev_events
+                for ev in events
+                for e_id, _ in ev.prev_events
             ],
         )
 
-        # Update the extremities table if this is not an outlier.
-        if not outlier:
-            for e_id, _ in prev_events:
-                # TODO (erikj): This could be done as a bulk insert
-                self._simple_delete_txn(
-                    txn,
-                    table="event_forward_extremities",
-                    keyvalues={
-                        "event_id": e_id,
-                        "room_id": room_id,
-                    }
-                )
+        events_by_room = {}
+        for ev in events:
+            events_by_room.setdefault(ev.room_id, []).append(ev)
 
-            # We only insert as a forward extremity the new event if there are
-            # no other events that reference it as a prev event
-            query = (
-                "SELECT 1 FROM event_edges WHERE prev_event_id = ?"
-            )
+        for room_id, room_events in events_by_room.items():
+            prevs = [
+                e_id for ev in room_events for e_id, _ in ev.prev_events
+                if not ev.internal_metadata.is_outlier()
+            ]
+            if prevs:
+                txn.execute(
+                    "DELETE FROM event_forward_extremities"
+                    " WHERE room_id = ?"
+                    " AND event_id in (%s)" % (
+                        ",".join(["?"] * len(prevs)),
+                    ),
+                    [room_id] + prevs,
+                )
 
-            txn.execute(query, (event_id,))
+        query = (
+            "INSERT INTO event_forward_extremities (event_id, room_id)"
+            " SELECT ?, ? WHERE NOT EXISTS ("
+            " SELECT 1 FROM event_edges WHERE prev_event_id = ?"
+            " )"
+        )
 
-            if not txn.fetchone():
-                query = (
-                    "INSERT INTO event_forward_extremities"
-                    " (event_id, room_id)"
-                    " VALUES (?, ?)"
-                )
+        txn.executemany(
+            query,
+            [(ev.event_id, ev.room_id, ev.event_id) for ev in events]
+        )
 
-                txn.execute(query, (event_id, room_id))
-
-            query = (
-                "INSERT INTO event_backward_extremities (event_id, room_id)"
-                " SELECT ?, ? WHERE NOT EXISTS ("
-                " SELECT 1 FROM event_backward_extremities"
-                " WHERE event_id = ? AND room_id = ?"
-                " )"
-                " AND NOT EXISTS ("
-                " SELECT 1 FROM events WHERE event_id = ? AND room_id = ? "
-                " AND outlier = ?"
-                " )"
-            )
+        query = (
+            "INSERT INTO event_backward_extremities (event_id, room_id)"
+            " SELECT ?, ? WHERE NOT EXISTS ("
+            " SELECT 1 FROM event_backward_extremities"
+            " WHERE event_id = ? AND room_id = ?"
+            " )"
+            " AND NOT EXISTS ("
+            " SELECT 1 FROM events WHERE event_id = ? AND room_id = ? "
+            " AND outlier = ?"
+            " )"
+        )
 
-            txn.executemany(query, [
-                (e_id, room_id, e_id, room_id, e_id, room_id, False)
-                for e_id, _ in prev_events
-            ])
+        txn.executemany(query, [
+            (e_id, ev.room_id, e_id, ev.room_id, e_id, ev.room_id, False)
+            for ev in events for e_id, _ in ev.prev_events
+            if not ev.internal_metadata.is_outlier()
+        ])
 
-            query = (
-                "DELETE FROM event_backward_extremities"
-                " WHERE event_id = ? AND room_id = ?"
-            )
-            txn.execute(query, (event_id, room_id))
+        query = (
+            "DELETE FROM event_backward_extremities"
+            " WHERE event_id = ? AND room_id = ?"
+        )
+        txn.executemany(
+            query,
+            [(ev.event_id, ev.room_id) for ev in events]
+        )
 
+        for room_id in events_by_room:
             txn.call_after(
                 self.get_latest_event_ids_in_room.invalidate, room_id
             )
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 2caf0aae80..ed7ea38804 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -23,9 +23,7 @@ from synapse.events.utils import prune_event
 from synapse.util.logcontext import preserve_context_over_deferred
 from synapse.util.logutils import log_function
 from synapse.api.constants import EventTypes
-from synapse.crypto.event_signing import compute_event_reference_hash
 
-from syutil.base64util import decode_base64
 from syutil.jsonutil import encode_json
 from contextlib import contextmanager
 
@@ -47,6 +45,48 @@ EVENT_QUEUE_TIMEOUT_S = 0.1  # Timeout when waiting for requests for events
 
 class EventsStore(SQLBaseStore):
     @defer.inlineCallbacks
+    def persist_events(self, events_and_contexts, backfilled=False,
+                       is_new_state=True):
+        if not events_and_contexts:
+            return
+
+        if backfilled:
+            if not self.min_token_deferred.called:
+                yield self.min_token_deferred
+            start = self.min_token - 1
+            self.min_token -= len(events_and_contexts) + 1
+            stream_orderings = range(start, self.min_token, -1)
+
+            @contextmanager
+            def stream_ordering_manager():
+                yield stream_orderings
+            stream_ordering_manager = stream_ordering_manager()
+        else:
+            stream_ordering_manager = yield self._stream_id_gen.get_next_mult(
+                self, len(events_and_contexts)
+            )
+
+        with stream_ordering_manager as stream_orderings:
+            for (event, _), stream in zip(events_and_contexts, stream_orderings):
+                event.internal_metadata.stream_ordering = stream
+
+            chunks = [
+                events_and_contexts[x:x+100]
+                for x in xrange(0, len(events_and_contexts), 100)
+            ]
+
+            for chunk in chunks:
+                # We can't easily parallelize these since different chunks
+                # might contain the same event. :(
+                yield self.runInteraction(
+                    "persist_events",
+                    self._persist_events_txn,
+                    events_and_contexts=chunk,
+                    backfilled=backfilled,
+                    is_new_state=is_new_state,
+                )
+
+    @defer.inlineCallbacks
     @log_function
     def persist_event(self, event, context, backfilled=False,
                       is_new_state=True, current_state=None):
@@ -67,13 +107,13 @@ class EventsStore(SQLBaseStore):
 
         try:
             with stream_ordering_manager as stream_ordering:
+                event.internal_metadata.stream_ordering = stream_ordering
                 yield self.runInteraction(
                     "persist_event",
                     self._persist_event_txn,
                     event=event,
                     context=context,
                     backfilled=backfilled,
-                    stream_ordering=stream_ordering,
                     is_new_state=is_new_state,
                     current_state=current_state,
                 )
@@ -116,12 +156,7 @@ class EventsStore(SQLBaseStore):
 
     @log_function
     def _persist_event_txn(self, txn, event, context, backfilled,
-                           stream_ordering=None, is_new_state=True,
-                           current_state=None):
-
-        # Remove the any existing cache entries for the event_id
-        txn.call_after(self._invalidate_get_event_cache, event.event_id)
-
+                           is_new_state=True, current_state=None):
         # We purposefully do this first since if we include a `current_state`
         # key, we *want* to update the `current_state_events` table
         if current_state:
@@ -149,37 +184,78 @@ class EventsStore(SQLBaseStore):
                     }
                 )
 
-        outlier = event.internal_metadata.is_outlier()
+        return self._persist_events_txn(
+            txn,
+            [(event, context)],
+            backfilled=backfilled,
+            is_new_state=is_new_state,
+        )
 
-        if not outlier:
-            self._update_min_depth_for_room_txn(
-                txn,
-                event.room_id,
-                event.depth
+    @log_function
+    def _persist_events_txn(self, txn, events_and_contexts, backfilled,
+                            is_new_state=True):
+
+        # Remove the any existing cache entries for the event_ids
+        for event, _ in events_and_contexts:
+            txn.call_after(self._invalidate_get_event_cache, event.event_id)
+
+        depth_updates = {}
+        for event, _ in events_and_contexts:
+            if event.internal_metadata.is_outlier():
+                continue
+            depth_updates[event.room_id] = max(
+                event.depth, depth_updates.get(event.room_id, event.depth)
             )
 
-        have_persisted = self._simple_select_one_txn(
-            txn,
-            table="events",
-            keyvalues={"event_id": event.event_id},
-            retcols=["event_id", "outlier"],
-            allow_none=True,
+        for room_id, depth in depth_updates.items():
+            self._update_min_depth_for_room_txn(txn, room_id, depth)
+
+        txn.execute(
+            "SELECT event_id, outlier FROM events WHERE event_id in (%s)" % (
+                ",".join(["?"] * len(events_and_contexts)),
+            ),
+            [event.event_id for event, _ in events_and_contexts]
         )
+        have_persisted = {
+            event_id: outlier
+            for event_id, outlier in txn.fetchall()
+        }
+
+        event_map = {}
+        to_remove = set()
+        for event, context in events_and_contexts:
+            # Handle the case of the list including the same event multiple
+            # times. The tricky thing here is when they differ by whether
+            # they are an outlier.
+            if event.event_id in event_map:
+                other = event_map[event.event_id]
+
+                if not other.internal_metadata.is_outlier():
+                    to_remove.add(event)
+                    continue
+                elif not event.internal_metadata.is_outlier():
+                    to_remove.add(event)
+                    continue
+                else:
+                    to_remove.add(other)
+
+            event_map[event.event_id] = event
 
-        metadata_json = encode_json(
-            event.internal_metadata.get_dict(),
-            using_frozen_dicts=USE_FROZEN_DICTS
-        ).decode("UTF-8")
-
-        # If we have already persisted this event, we don't need to do any
-        # more processing.
-        # The processing above must be done on every call to persist event,
-        # since they might not have happened on previous calls. For example,
-        # if we are persisting an event that we had persisted as an outlier,
-        # but is no longer one.
-        if have_persisted:
-            if not outlier and have_persisted["outlier"]:
-                self._store_state_groups_txn(txn, event, context)
+            if event.event_id not in have_persisted:
+                continue
+
+            to_remove.add(event)
+
+            outlier_persisted = have_persisted[event.event_id]
+            if not event.internal_metadata.is_outlier() and outlier_persisted:
+                self._store_state_groups_txn(
+                    txn, event, context,
+                )
+
+                metadata_json = encode_json(
+                    event.internal_metadata.get_dict(),
+                    using_frozen_dicts=USE_FROZEN_DICTS
+                ).decode("UTF-8")
 
                 sql = (
                     "UPDATE event_json SET internal_metadata = ?"
@@ -198,94 +274,91 @@ class EventsStore(SQLBaseStore):
                     sql,
                     (False, event.event_id,)
                 )
-            return
 
-        if not outlier:
-            self._store_state_groups_txn(txn, event, context)
-
-        self._handle_prev_events(
-            txn,
-            outlier=outlier,
-            event_id=event.event_id,
-            prev_events=event.prev_events,
-            room_id=event.room_id,
+        events_and_contexts = filter(
+            lambda ec: ec[0] not in to_remove,
+            events_and_contexts
         )
 
-        if event.type == EventTypes.Member:
-            self._store_room_member_txn(txn, event)
-        elif event.type == EventTypes.Name:
-            self._store_room_name_txn(txn, event)
-        elif event.type == EventTypes.Topic:
-            self._store_room_topic_txn(txn, event)
-        elif event.type == EventTypes.Redaction:
-            self._store_redaction(txn, event)
-
-        event_dict = {
-            k: v
-            for k, v in event.get_dict().items()
-            if k not in [
-                "redacted",
-                "redacted_because",
-            ]
-        }
+        if not events_and_contexts:
+            return
+
+        self._store_mult_state_groups_txn(txn, [
+            (event, context)
+            for event, context in events_and_contexts
+            if not event.internal_metadata.is_outlier()
+        ])
 
-        self._simple_insert_txn(
+        self._handle_mult_prev_events(
             txn,
-            table="event_json",
-            values={
-                "event_id": event.event_id,
-                "room_id": event.room_id,
-                "internal_metadata": metadata_json,
-                "json": encode_json(
-                    event_dict, using_frozen_dicts=USE_FROZEN_DICTS
-                ).decode("UTF-8"),
-            },
+            events=[event for event, _ in events_and_contexts],
         )
 
-        content = encode_json(
-            event.content, using_frozen_dicts=USE_FROZEN_DICTS
-        ).decode("UTF-8")
-
-        vals = {
-            "topological_ordering": event.depth,
-            "event_id": event.event_id,
-            "type": event.type,
-            "room_id": event.room_id,
-            "content": content,
-            "processed": True,
-            "outlier": outlier,
-            "depth": event.depth,
-        }
+        for event, _ in events_and_contexts:
+            if event.type == EventTypes.Name:
+                self._store_room_name_txn(txn, event)
+            elif event.type == EventTypes.Topic:
+                self._store_room_topic_txn(txn, event)
+            elif event.type == EventTypes.Redaction:
+                self._store_redaction(txn, event)
 
-        unrec = {
-            k: v
-            for k, v in event.get_dict().items()
-            if k not in vals.keys() and k not in [
-                "redacted",
-                "redacted_because",
-                "signatures",
-                "hashes",
-                "prev_events",
+        self._store_room_members_txn(
+            txn,
+            [
+                event
+                for event, _ in events_and_contexts
+                if event.type == EventTypes.Member
             ]
-        }
+        )
 
-        vals["unrecognized_keys"] = encode_json(
-            unrec, using_frozen_dicts=USE_FROZEN_DICTS
-        ).decode("UTF-8")
+        def event_dict(event):
+            return {
+                k: v
+                for k, v in event.get_dict().items()
+                if k not in [
+                    "redacted",
+                    "redacted_because",
+                ]
+            }
 
-        sql = (
-            "INSERT INTO events"
-            " (stream_ordering, topological_ordering, event_id, type,"
-            " room_id, content, processed, outlier, depth)"
-            " VALUES (?,?,?,?,?,?,?,?,?)"
+        self._simple_insert_many_txn(
+            txn,
+            table="event_json",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "room_id": event.room_id,
+                    "internal_metadata": encode_json(
+                        event.internal_metadata.get_dict(),
+                        using_frozen_dicts=USE_FROZEN_DICTS
+                    ).decode("UTF-8"),
+                    "json": encode_json(
+                        event_dict(event), using_frozen_dicts=USE_FROZEN_DICTS
+                    ).decode("UTF-8"),
+                }
+                for event, _ in events_and_contexts
+            ],
         )
 
-        txn.execute(
-            sql,
-            (
-                stream_ordering, event.depth, event.event_id, event.type,
-                event.room_id, content, True, outlier, event.depth
-            )
+        self._simple_insert_many_txn(
+            txn,
+            table="events",
+            values=[
+                {
+                    "stream_ordering": event.internal_metadata.stream_ordering,
+                    "topological_ordering": event.depth,
+                    "depth": event.depth,
+                    "event_id": event.event_id,
+                    "room_id": event.room_id,
+                    "type": event.type,
+                    "processed": True,
+                    "outlier": event.internal_metadata.is_outlier(),
+                    "content": encode_json(
+                        event.content, using_frozen_dicts=USE_FROZEN_DICTS
+                    ).decode("UTF-8"),
+                }
+                for event, _ in events_and_contexts
+            ],
         )
 
         if context.rejected:
@@ -293,20 +366,6 @@ class EventsStore(SQLBaseStore):
                 txn, event.event_id, context.rejected
             )
 
-        for hash_alg, hash_base64 in event.hashes.items():
-            hash_bytes = decode_base64(hash_base64)
-            self._store_event_content_hash_txn(
-                txn, event.event_id, hash_alg, hash_bytes,
-            )
-
-        for prev_event_id, prev_hashes in event.prev_events:
-            for alg, hash_base64 in prev_hashes.items():
-                hash_bytes = decode_base64(hash_base64)
-                self._store_prev_event_hash_txn(
-                    txn, event.event_id, prev_event_id, alg,
-                    hash_bytes
-                )
-
         self._simple_insert_many_txn(
             txn,
             table="event_auth",
@@ -316,16 +375,22 @@ class EventsStore(SQLBaseStore):
                     "room_id": event.room_id,
                     "auth_id": auth_id,
                 }
+                for event, _ in events_and_contexts
                 for auth_id, _ in event.auth_events
             ],
         )
 
-        (ref_alg, ref_hash_bytes) = compute_event_reference_hash(event)
-        self._store_event_reference_hash_txn(
-            txn, event.event_id, ref_alg, ref_hash_bytes
+        self._store_event_reference_hashes_txn(
+            txn, [event for event, _ in events_and_contexts]
+        )
+
+        state_events_and_contexts = filter(
+            lambda i: i[0].is_state(),
+            events_and_contexts,
         )
 
-        if event.is_state():
+        state_values = []
+        for event, context in state_events_and_contexts:
             vals = {
                 "event_id": event.event_id,
                 "room_id": event.room_id,
@@ -337,52 +402,56 @@ class EventsStore(SQLBaseStore):
             if hasattr(event, "replaces_state"):
                 vals["prev_state"] = event.replaces_state
 
-            self._simple_insert_txn(
-                txn,
-                "state_events",
-                vals,
-            )
+            state_values.append(vals)
 
-            self._simple_insert_many_txn(
-                txn,
-                table="event_edges",
-                values=[
-                    {
-                        "event_id": event.event_id,
-                        "prev_event_id": e_id,
-                        "room_id": event.room_id,
-                        "is_state": True,
-                    }
-                    for e_id, h in event.prev_state
-                ],
-            )
+        self._simple_insert_many_txn(
+            txn,
+            table="state_events",
+            values=state_values,
+        )
 
-            if is_new_state and not context.rejected:
-                txn.call_after(
-                    self.get_current_state_for_key.invalidate,
-                    event.room_id, event.type, event.state_key
-                )
+        self._simple_insert_many_txn(
+            txn,
+            table="event_edges",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "prev_event_id": prev_id,
+                    "room_id": event.room_id,
+                    "is_state": True,
+                }
+                for event, _ in state_events_and_contexts
+                for prev_id, _ in event.prev_state
+            ],
+        )
 
-                if (event.type == EventTypes.Name
-                        or event.type == EventTypes.Aliases):
+        if is_new_state:
+            for event, _ in state_events_and_contexts:
+                if not context.rejected:
                     txn.call_after(
-                        self.get_room_name_and_aliases.invalidate,
-                        event.room_id
+                        self.get_current_state_for_key.invalidate,
+                        event.room_id, event.type, event.state_key
+                        )
+
+                    if event.type in [EventTypes.Name, EventTypes.Aliases]:
+                        txn.call_after(
+                            self.get_room_name_and_aliases.invalidate,
+                            event.room_id
+                        )
+
+                    self._simple_upsert_txn(
+                        txn,
+                        "current_state_events",
+                        keyvalues={
+                            "room_id": event.room_id,
+                            "type": event.type,
+                            "state_key": event.state_key,
+                        },
+                        values={
+                            "event_id": event.event_id,
+                        }
                     )
 
-                self._simple_upsert_txn(
-                    txn,
-                    "current_state_events",
-                    keyvalues={
-                        "room_id": event.room_id,
-                        "type": event.type,
-                        "state_key": event.state_key,
-                    },
-                    values={
-                        "event_id": event.event_id,
-                    }
-                )
-
         return
 
     def _store_redaction(self, txn, event):
diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py
index d36a6c18a8..4db07f6fb4 100644
--- a/synapse/storage/roommember.py
+++ b/synapse/storage/roommember.py
@@ -35,38 +35,28 @@ RoomsForUser = namedtuple(
 
 class RoomMemberStore(SQLBaseStore):
 
-    def _store_room_member_txn(self, txn, event):
+    def _store_room_members_txn(self, txn, events):
         """Store a room member in the database.
         """
-        try:
-            target_user_id = event.state_key
-        except:
-            logger.exception(
-                "Failed to parse target_user_id=%s", target_user_id
-            )
-            raise
-
-        logger.debug(
-            "_store_room_member_txn: target_user_id=%s, membership=%s",
-            target_user_id,
-            event.membership,
-        )
-
-        self._simple_insert_txn(
+        self._simple_insert_many_txn(
             txn,
-            "room_memberships",
-            {
-                "event_id": event.event_id,
-                "user_id": target_user_id,
-                "sender": event.user_id,
-                "room_id": event.room_id,
-                "membership": event.membership,
-            }
+            table="room_memberships",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "user_id": event.state_key,
+                    "sender": event.user_id,
+                    "room_id": event.room_id,
+                    "membership": event.membership,
+                }
+                for event in events
+            ]
         )
 
-        txn.call_after(self.get_rooms_for_user.invalidate, target_user_id)
-        txn.call_after(self.get_joined_hosts_for_room.invalidate, event.room_id)
-        txn.call_after(self.get_users_in_room.invalidate, event.room_id)
+        for event in events:
+            txn.call_after(self.get_rooms_for_user.invalidate, event.state_key)
+            txn.call_after(self.get_joined_hosts_for_room.invalidate, event.room_id)
+            txn.call_after(self.get_users_in_room.invalidate, event.room_id)
 
     def get_room_member(self, user_id, room_id):
         """Retrieve the current state of a room member.
diff --git a/synapse/storage/signatures.py b/synapse/storage/signatures.py
index f051828630..4f15e534b4 100644
--- a/synapse/storage/signatures.py
+++ b/synapse/storage/signatures.py
@@ -18,6 +18,7 @@ from twisted.internet import defer
 from _base import SQLBaseStore
 
 from syutil.base64util import encode_base64
+from synapse.crypto.event_signing import compute_event_reference_hash
 
 
 class SignatureStore(SQLBaseStore):
@@ -101,23 +102,26 @@ class SignatureStore(SQLBaseStore):
         txn.execute(query, (event_id, ))
         return {k: v for k, v in txn.fetchall()}
 
-    def _store_event_reference_hash_txn(self, txn, event_id, algorithm,
-                                        hash_bytes):
+    def _store_event_reference_hashes_txn(self, txn, events):
         """Store a hash for a PDU
         Args:
             txn (cursor):
-            event_id (str): Id for the Event.
-            algorithm (str): Hashing algorithm.
-            hash_bytes (bytes): Hash function output bytes.
+            events (list): list of Events.
         """
-        self._simple_insert_txn(
+
+        vals = []
+        for event in events:
+            ref_alg, ref_hash_bytes = compute_event_reference_hash(event)
+            vals.append({
+                "event_id": event.event_id,
+                "algorithm": ref_alg,
+                "hash": buffer(ref_hash_bytes),
+            })
+
+        self._simple_insert_many_txn(
             txn,
-            "event_reference_hashes",
-            {
-                "event_id": event_id,
-                "algorithm": algorithm,
-                "hash": buffer(hash_bytes),
-            },
+            table="event_reference_hashes",
+            values=vals,
         )
 
     def _get_event_signatures_txn(self, txn, event_id):
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index d7844edee3..47bec65497 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -100,16 +100,23 @@ class StateStore(SQLBaseStore):
         )
 
     def _store_state_groups_txn(self, txn, event, context):
-        if context.current_state is None:
-            return
+        return self._store_mult_state_groups_txn(txn, [(event, context)])
 
-        state_events = dict(context.current_state)
+    def _store_mult_state_groups_txn(self, txn, events_and_contexts):
+        state_groups = {}
+        for event, context in events_and_contexts:
+            if context.current_state is None:
+                continue
 
-        if event.is_state():
-            state_events[(event.type, event.state_key)] = event
+            if context.state_group is not None:
+                state_groups[event.event_id] = context.state_group
+                continue
+
+            state_events = dict(context.current_state)
+
+            if event.is_state():
+                state_events[(event.type, event.state_key)] = event
 
-        state_group = context.state_group
-        if not state_group:
             state_group = self._state_groups_id_gen.get_next_txn(txn)
             self._simple_insert_txn(
                 txn,
@@ -135,14 +142,19 @@ class StateStore(SQLBaseStore):
                     for state in state_events.values()
                 ],
             )
+            state_groups[event.event_id] = state_group
 
-        self._simple_insert_txn(
+        self._simple_insert_many_txn(
             txn,
             table="event_to_state_groups",
-            values={
-                "state_group": state_group,
-                "event_id": event.event_id,
-            },
+            values=[
+                {
+                    "state_group": state_groups[event.event_id],
+                    "event_id": event.event_id,
+                }
+                for event, context in events_and_contexts
+                if context.current_state is not None
+            ],
         )
 
     @defer.inlineCallbacks
diff --git a/synapse/storage/util/id_generators.py b/synapse/storage/util/id_generators.py
index 89d1643f10..83eab63098 100644
--- a/synapse/storage/util/id_generators.py
+++ b/synapse/storage/util/id_generators.py
@@ -108,6 +108,37 @@ class StreamIdGenerator(object):
         defer.returnValue(manager())
 
     @defer.inlineCallbacks
+    def get_next_mult(self, store, n):
+        """
+        Usage:
+            with yield stream_id_gen.get_next(store, n) as stream_ids:
+                # ... persist events ...
+        """
+        if not self._current_max:
+            yield store.runInteraction(
+                "_compute_current_max",
+                self._get_or_compute_current_max,
+            )
+
+        with self._lock:
+            next_ids = range(self._current_max + 1, self._current_max + n + 1)
+            self._current_max += n
+
+            for next_id in next_ids:
+                self._unfinished_ids.append(next_id)
+
+        @contextlib.contextmanager
+        def manager():
+            try:
+                yield next_ids
+            finally:
+                with self._lock:
+                    for next_id in next_ids:
+                        self._unfinished_ids.remove(next_id)
+
+        defer.returnValue(manager())
+
+    @defer.inlineCallbacks
     def get_max_token(self, store):
         """Returns the maximum stream id such that all stream ids less than or
         equal to it have been successfully persisted.