1 files changed, 3 insertions, 1 deletions
diff --git a/synapse/storage/transactions.py b/synapse/storage/transactions.py
index 58d4de4f1d..5055c04b24 100644
--- a/synapse/storage/transactions.py
+++ b/synapse/storage/transactions.py
@@ -245,7 +245,7 @@ class TransactionStore(SQLBaseStore):
 
         return self.cursor_to_dict(txn)
 
-    @cached()
+    @cached(max_entries=10000)
     def get_destination_retry_timings(self, destination):
         """Gets the current retry timings (if any) for a given destination.
 
@@ -387,8 +387,10 @@ class TransactionStore(SQLBaseStore):
     def _cleanup_transactions(self):
         now = self._clock.time_msec()
         month_ago = now - 30 * 24 * 60 * 60 * 1000
+        six_hours_ago = now - 6 * 60 * 60 * 1000
 
         def _cleanup_transactions_txn(txn):
             txn.execute("DELETE FROM received_transactions WHERE ts < ?", (month_ago,))
+            txn.execute("DELETE FROM sent_transactions WHERE ts < ?", (six_hours_ago,))
 
         return self.runInteraction("_persist_in_mem_txns", _cleanup_transactions_txn)