From 299b00d968ee23ba4e4806dd7c4fa97c7fcfb6f5 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 27 Sep 2022 15:17:41 +0100 Subject: [PATCH] Prioritize outbound to-device over device list updates (#13922) Otherwise device list changes for large accounts can temporarily delay to-device messages. --- changelog.d/13922.bugfix | 1 + .../sender/per_destination_queue.py | 29 ++++++++++--------- 2 files changed, 17 insertions(+), 13 deletions(-) create mode 100644 changelog.d/13922.bugfix diff --git a/changelog.d/13922.bugfix b/changelog.d/13922.bugfix new file mode 100644 index 000000000000..7269d28dee75 --- /dev/null +++ b/changelog.d/13922.bugfix @@ -0,0 +1 @@ +Fix long-standing bug where device updates could cause delays sending out to-device messages over federation. diff --git a/synapse/federation/sender/per_destination_queue.py b/synapse/federation/sender/per_destination_queue.py index 41d8b937af4e..084c45a95ca1 100644 --- a/synapse/federation/sender/per_destination_queue.py +++ b/synapse/federation/sender/per_destination_queue.py @@ -646,29 +646,32 @@ async def __aenter__(self) -> Tuple[List[EventBase], List[Edu]]: # We start by fetching device related EDUs, i.e device updates and to # device messages. We have to keep 2 free slots for presence and rr_edus. - limit = MAX_EDUS_PER_TRANSACTION - 2 - - device_update_edus, dev_list_id = await self.queue._get_device_update_edus( - limit - ) - - if device_update_edus: - self._device_list_id = dev_list_id - else: - self.queue._last_device_list_stream_id = dev_list_id - - limit -= len(device_update_edus) + device_edu_limit = MAX_EDUS_PER_TRANSACTION - 2 + # We prioritize to-device messages so that existing encryption channels + # work. We also keep a few slots spare (by reducing the limit) so that + # we can still trickle out some device list updates. ( to_device_edus, device_stream_id, - ) = await self.queue._get_to_device_message_edus(limit) + ) = await self.queue._get_to_device_message_edus(device_edu_limit - 10) if to_device_edus: self._device_stream_id = device_stream_id else: self.queue._last_device_stream_id = device_stream_id + device_edu_limit -= len(to_device_edus) + + device_update_edus, dev_list_id = await self.queue._get_device_update_edus( + device_edu_limit + ) + + if device_update_edus: + self._device_list_id = dev_list_id + else: + self.queue._last_device_list_stream_id = dev_list_id + pending_edus = device_update_edus + to_device_edus # Now add the read receipt EDU.