diff --git a/synapse/federation/persistence.py b/synapse/federation/persistence.py
index 865766eb2c..1a7cc02f92 100644
--- a/synapse/federation/persistence.py
+++ b/synapse/federation/persistence.py
@@ -99,5 +99,5 @@ class TransactionActions(object):
             transaction.transaction_id,
             transaction.destination,
             response_code,
-            encode_canonical_json(response_dict)
+            response_dict,
         )
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index a2da3dd1b1..ee5587c721 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -206,18 +206,23 @@ class LoggingTransaction(object):
     def __setattr__(self, name, value):
         setattr(self.txn, name, value)
 
-    def execute(self, sql, *args, **kwargs):
+    def execute(self, sql, *args):
+        self._do_execute(self.txn.execute, sql, *args)
+
+    def executemany(self, sql, *args):
+        self._do_execute(self.txn.executemany, sql, *args)
+
+    def _do_execute(self, func, sql, *args):
         # TODO(paul): Maybe use 'info' and 'debug' for values?
         sql_logger.debug("[SQL] {%s} %s", self.name, sql)
 
         sql = self.database_engine.convert_param_style(sql)
 
-        if args and args[0]:
+        if args:
             try:
                 sql_logger.debug(
-                    "[SQL values] {%s} " + ", ".join(("<%r>",) * len(args[0])),
-                    self.name,
-                    *args[0]
+                    "[SQL values] {%s} %r",
+                    self.name, args[0]
                 )
             except:
                 # Don't let logging failures stop SQL from working
@@ -226,8 +231,8 @@ class LoggingTransaction(object):
         start = time.time() * 1000
 
         try:
-            return self.txn.execute(
-                sql, *args, **kwargs
+            return func(
+                sql, *args
             )
         except Exception as e:
             logger.debug("[SQL FAIL] {%s} %s", self.name, e)
@@ -484,18 +489,49 @@ class SQLBaseStore(object):
 
     @log_function
     def _simple_insert_txn(self, txn, table, values):
+        keys, vals = zip(*values.items())
+
         sql = "INSERT INTO %s (%s) VALUES(%s)" % (
             table,
-            ", ".join(k for k in values),
-            ", ".join("?" for k in values)
+            ", ".join(k for k in keys),
+            ", ".join("?" for _ in keys)
         )
 
-        logger.debug(
-            "[SQL] %s Args=%s",
-            sql, values.values(),
+        txn.execute(sql, vals)
+
+    def _simple_insert_many_txn(self, txn, table, values):
+        if not values:
+            return
+
+        # This is a *slight* abomination to get a list of tuples of key names
+        # and a list of tuples of value names.
+        #
+        # i.e. [{"a": 1, "b": 2}, {"c": 3, "d": 4}]
+        #         => [("a", "b",), ("c", "d",)] and [(1, 2,), (3, 4,)]
+        #
+        # The sort is to ensure that we don't rely on dictionary iteration
+        # order.
+        keys, vals = zip(*[
+            zip(
+                *(sorted(i.items(), key=lambda kv: kv[0]))
+            )
+            for i in values
+            if i
+        ])
+
+        for k in keys:
+            if k != keys[0]:
+                raise RuntimeError(
+                    "All items must have the same keys"
+                )
+
+        sql = "INSERT INTO %s (%s) VALUES(%s)" % (
+            table,
+            ", ".join(k for k in keys[0]),
+            ", ".join("?" for _ in keys[0])
         )
 
-        txn.execute(sql, values.values())
+        txn.executemany(sql, vals)
 
     def _simple_upsert(self, table, keyvalues, values,
                        insertion_values={}, desc="_simple_upsert", lock=True):
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index 893344eff3..74b4e23590 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -262,18 +262,19 @@ class EventFederationStore(SQLBaseStore):
         For the given event, update the event edges table and forward and
         backward extremities tables.
         """
-        for e_id, _ in prev_events:
-            # TODO (erikj): This could be done as a bulk insert
-            self._simple_insert_txn(
-                txn,
-                table="event_edges",
-                values={
+        self._simple_insert_many_txn(
+            txn,
+            table="event_edges",
+            values=[
+                {
                     "event_id": event_id,
                     "prev_event_id": e_id,
                     "room_id": room_id,
                     "is_state": False,
-                },
-            )
+                }
+                for e_id, _ in prev_events
+            ],
+        )
 
         # Update the extremities table if this is not an outlier.
         if not outlier:
@@ -307,16 +308,17 @@ class EventFederationStore(SQLBaseStore):
 
             # Insert all the prev_events as a backwards thing, they'll get
             # deleted in a second if they're incorrect anyway.
-            for e_id, _ in prev_events:
-                # TODO (erikj): This could be done as a bulk insert
-                self._simple_insert_txn(
-                    txn,
-                    table="event_backward_extremities",
-                    values={
+            self._simple_insert_many_txn(
+                txn,
+                table="event_backward_extremities",
+                values=[
+                    {
                         "event_id": e_id,
                         "room_id": room_id,
-                    },
-                )
+                    }
+                    for e_id, _ in prev_events
+                ],
+            )
 
             # Also delete from the backwards extremities table all ones that
             # reference events that we have already seen
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 17f9d27289..ba180da56d 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -129,7 +129,7 @@ class EventsStore(SQLBaseStore):
                         "room_id": s.room_id,
                         "type": s.type,
                         "state_key": s.state_key,
-                    },
+                    }
                 )
 
         if event.is_state() and is_new_state:
@@ -306,16 +306,18 @@ class EventsStore(SQLBaseStore):
                     hash_bytes
                 )
 
-        for auth_id, _ in event.auth_events:
-            self._simple_insert_txn(
-                txn,
-                table="event_auth",
-                values={
+        self._simple_insert_many_txn(
+            txn,
+            table="event_auth",
+            values=[
+                {
                     "event_id": event.event_id,
                     "room_id": event.room_id,
                     "auth_id": auth_id,
-                },
-            )
+                }
+                for auth_id, _ in event.auth_events
+            ],
+        )
 
         (ref_alg, ref_hash_bytes) = compute_event_reference_hash(event)
         self._store_event_reference_hash_txn(
@@ -340,17 +342,19 @@ class EventsStore(SQLBaseStore):
                 vals,
             )
 
-            for e_id, h in event.prev_state:
-                self._simple_insert_txn(
-                    txn,
-                    table="event_edges",
-                    values={
+            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
+                ],
+            )
 
             if is_new_state and not context.rejected:
                 self._simple_upsert_txn(
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index 7e55e8bed6..dbc0e49c1f 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -104,18 +104,20 @@ class StateStore(SQLBaseStore):
                 },
             )
 
-            for state in state_events.values():
-                self._simple_insert_txn(
-                    txn,
-                    table="state_groups_state",
-                    values={
+            self._simple_insert_many_txn(
+                txn,
+                table="state_groups_state",
+                values=[
+                    {
                         "state_group": state_group,
                         "room_id": state.room_id,
                         "type": state.type,
                         "state_key": state.state_key,
                         "event_id": state.event_id,
-                    },
-                )
+                    }
+                    for state in state_events.values()
+                ],
+            )
 
         self._simple_insert_txn(
             txn,
diff --git a/synapse/storage/transactions.py b/synapse/storage/transactions.py
index b5b21a9b13..624da4a9dc 100644
--- a/synapse/storage/transactions.py
+++ b/synapse/storage/transactions.py
@@ -162,7 +162,8 @@ class TransactionStore(SQLBaseStore):
         return self.runInteraction(
             "delivered_txn",
             self._delivered_txn,
-            transaction_id, destination, code, response_dict
+            transaction_id, destination, code,
+            buffer(encode_canonical_json(response_dict)),
         )
 
     def _delivered_txn(self, txn, transaction_id, destination,
diff --git a/tests/storage/test_base.py b/tests/storage/test_base.py
index a64d2b821e..8c348ecc95 100644
--- a/tests/storage/test_base.py
+++ b/tests/storage/test_base.py
@@ -67,7 +67,7 @@ class SQLBaseStoreTestCase(unittest.TestCase):
 
         self.mock_txn.execute.assert_called_with(
                 "INSERT INTO tablename (columname) VALUES(?)",
-                ["Value"]
+                ("Value",)
         )
 
     @defer.inlineCallbacks
@@ -82,7 +82,7 @@ class SQLBaseStoreTestCase(unittest.TestCase):
 
         self.mock_txn.execute.assert_called_with(
                 "INSERT INTO tablename (colA, colB, colC) VALUES(?, ?, ?)",
-                [1, 2, 3]
+                (1, 2, 3,)
         )
 
     @defer.inlineCallbacks