diff options
| -rw-r--r-- | changelog.d/15150.bugfix | 1 | ||||
| -rw-r--r-- | synapse/replication/tcp/resource.py | 18 | ||||
| -rw-r--r-- | tests/replication/tcp/test_handler.py | 61 |
3 files changed, 80 insertions, 0 deletions
diff --git a/changelog.d/15150.bugfix b/changelog.d/15150.bugfix new file mode 100644 index 0000000000..8668bc587f --- /dev/null +++ b/changelog.d/15150.bugfix @@ -0,0 +1 @@ +Fix a bug introduced in Synapse 1.76 where 5s delays would occasionally occur in deployments using workers. diff --git a/synapse/replication/tcp/resource.py b/synapse/replication/tcp/resource.py index 9d17eff714..347467d863 100644 --- a/synapse/replication/tcp/resource.py +++ b/synapse/replication/tcp/resource.py @@ -238,6 +238,24 @@ class ReplicationStreamer: except Exception: logger.exception("Failed to replicate") + # The last token we send may not match the current + # token, in which case we want to send out a `POSITION` + # to tell other workers the actual current position. + if updates[-1][0] < current_token: + logger.info( + "Sending position: %s -> %s", + stream.NAME, + current_token, + ) + self.command_handler.send_command( + PositionCommand( + stream.NAME, + self._instance_name, + updates[-1][0], + current_token, + ) + ) + logger.debug("No more pending updates, breaking poke loop") finally: self.pending_updates = False diff --git a/tests/replication/tcp/test_handler.py b/tests/replication/tcp/test_handler.py index bf927beb6a..bab77b2df7 100644 --- a/tests/replication/tcp/test_handler.py +++ b/tests/replication/tcp/test_handler.py @@ -141,3 +141,64 @@ class ChannelsTestCase(BaseMultiWorkerStreamTestCase): self.get_success(ctx_worker1.__aexit__(None, None, None)) self.assertTrue(d.called) + + def test_wait_for_stream_position_rdata(self) -> None: + """Check that wait for stream position correctly waits for an update + from the correct instance, when RDATA is sent. + """ + store = self.hs.get_datastores().main + cmd_handler = self.hs.get_replication_command_handler() + data_handler = self.hs.get_replication_data_handler() + + worker1 = self.make_worker_hs( + "synapse.app.generic_worker", + extra_config={ + "worker_name": "worker1", + "run_background_tasks_on": "worker1", + "redis": {"enabled": True}, + }, + ) + + cache_id_gen = worker1.get_datastores().main._cache_id_gen + assert cache_id_gen is not None + + self.replicate() + + # First, make sure the master knows that `worker1` exists. + initial_token = cache_id_gen.get_current_token() + cmd_handler.send_command( + PositionCommand("caches", "worker1", initial_token, initial_token) + ) + self.replicate() + + # `wait_for_stream_position` should only return once master receives a + # notification that `next_token2` has persisted. + ctx_worker1 = cache_id_gen.get_next_mult(2) + next_token1, next_token2 = self.get_success(ctx_worker1.__aenter__()) + + d = defer.ensureDeferred( + data_handler.wait_for_stream_position("worker1", "caches", next_token2) + ) + self.assertFalse(d.called) + + # Insert an entry into the cache stream with token `next_token1`, but + # not `next_token2`. + self.get_success( + store.db_pool.simple_insert( + table="cache_invalidation_stream_by_instance", + values={ + "stream_id": next_token1, + "instance_name": "worker1", + "cache_func": "foo", + "keys": [], + "invalidation_ts": 0, + }, + ) + ) + + # Finish the context manager, triggering the data to be sent to master. + self.get_success(ctx_worker1.__aexit__(None, None, None)) + + # Master should get told about `next_token2`, so the deferred should + # resolve. + self.assertTrue(d.called) |