Prefill the device_list_stream_cache (#12367)

* Prefill the device_list_stream_cache * Newsfile * Newsfile
matrix-org · Apr 4, 2022 · b446c99 · b446c99
1 parent 5c9e39e
commit b446c99
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Showing 3 changed files with 23 additions and 2 deletions.
diff --git a/changelog.d/12367.feature b/changelog.d/12367.feature
@@ -0,0 +1 @@
+Reduce overhead of restarting synchrotrons.
diff --git a/synapse/replication/slave/storage/devices.py b/synapse/replication/slave/storage/devices.py
@@ -48,8 +48,18 @@ def __init__(
             ],
         )
         device_list_max = self._device_list_id_gen.get_current_token()
+        device_list_prefill, min_device_list_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "device_lists_stream",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=device_list_max,
+            limit=1000,
+        )
         self._device_list_stream_cache = StreamChangeCache(
-            "DeviceListStreamChangeCache", device_list_max
+            "DeviceListStreamChangeCache",
+            min_device_list_id,
+            prefilled_cache=device_list_prefill,
         )
         self._user_signature_stream_cache = StreamChangeCache(
             "UserSignatureStreamChangeCache", device_list_max

diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
@@ -184,8 +184,18 @@ def __init__(
         super().__init__(database, db_conn, hs)
 
         device_list_max = self._device_list_id_gen.get_current_token()
+        device_list_prefill, min_device_list_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "device_lists_stream",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=device_list_max,
+            limit=1000,
+        )
         self._device_list_stream_cache = StreamChangeCache(
-            "DeviceListStreamChangeCache", device_list_max
+            "DeviceListStreamChangeCache",
+            min_device_list_id,
+            prefilled_cache=device_list_prefill,
         )
         self._user_signature_stream_cache = StreamChangeCache(
             "UserSignatureStreamChangeCache", device_list_max