1 files changed, 16 insertions, 4 deletions
diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index fba7ad9551..1ee266f7c5 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -65,6 +65,7 @@ from synapse.replication.slave.storage.registration import SlavedRegistrationSto
 from synapse.replication.slave.storage.room import RoomStore
 from synapse.replication.slave.storage.transactions import SlavedTransactionStore
 from synapse.replication.tcp.client import ReplicationClientHandler
+from synapse.replication.tcp.commands import ClearUserSyncsCommand
 from synapse.replication.tcp.streams import (
     AccountDataStream,
     DeviceListsStream,
@@ -124,7 +125,6 @@ from synapse.types import ReadReceipt
 from synapse.util.async_helpers import Linearizer
 from synapse.util.httpresourcetree import create_resource_tree
 from synapse.util.manhole import manhole
-from synapse.util.stringutils import random_string
 from synapse.util.versionstring import get_version_string
 
 logger = logging.getLogger("synapse.app.generic_worker")
@@ -233,6 +233,7 @@ class GenericWorkerPresence(object):
         self.user_to_num_current_syncs = {}
         self.clock = hs.get_clock()
         self.notifier = hs.get_notifier()
+        self.instance_id = hs.get_instance_id()
 
         active_presence = self.store.take_presence_startup_info()
         self.user_to_current_state = {state.user_id: state for state in active_presence}
@@ -245,13 +246,24 @@ class GenericWorkerPresence(object):
             self.send_stop_syncing, UPDATE_SYNCING_USERS_MS
         )
 
-        self.process_id = random_string(16)
-        logger.info("Presence process_id is %r", self.process_id)
+        hs.get_reactor().addSystemEventTrigger(
+            "before",
+            "shutdown",
+            run_as_background_process,
+            "generic_presence.on_shutdown",
+            self._on_shutdown,
+        )
+
+    def _on_shutdown(self):
+        if self.hs.config.use_presence:
+            self.hs.get_tcp_replication().send_command(
+                ClearUserSyncsCommand(self.instance_id)
+            )
 
     def send_user_sync(self, user_id, is_syncing, last_sync_ms):
         if self.hs.config.use_presence:
             self.hs.get_tcp_replication().send_user_sync(
-                user_id, is_syncing, last_sync_ms
+                self.instance_id, user_id, is_syncing, last_sync_ms
             )
 
     def mark_as_coming_online(self, user_id):