Mathieu Velten b89d578d56 Limit outgoing to_device EDU size to 65536 (#18416) ...

If a set of messages exceeds this limit, the messages are split
across several EDUs.

Fix #17035 (should)

There is currently [no official specced limit for
EDUs](https://github.com/matrix-org/matrix-spec/issues/807), but the
consensus seems to be that it would be useful to have one to avoid this
bug by bounding the transaction size.

As a side effect it also limits the size of a single to-device message
to a bit less than 65536.

This should probably be added to the spec similarly to the [message size
limit.](https://spec.matrix.org/v1.14/client-server-api/#size-limits)

Spec PR: https://github.com/matrix-org/matrix-spec/pull/2340

---------

Co-authored-by: mcalinghee <mcalinghee.dev@gmail.com>
Co-authored-by: Eric Eastwood <madlittlemods@gmail.com>

2026-03-27 12:01:31 +00:00

..

api

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

app

Be able to shutdown homeserver that hasn't setup (#19187)

2025-12-02 10:58:06 -06:00

appservice

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

config

Add a way to expose metrics from the Docker image (SYNAPSE_ENABLE_METRICS) (#19324)

2026-01-01 14:00:00 -06:00

crypto

Refuse requests and events signed by banned signing keys (#19459)

2026-02-12 16:39:59 +01:00

events

Remove redacted_because from internal unsigned. (#19581)

2026-03-26 09:18:08 +00:00

federation

Add unstable federation API for MSC4370 GET /extremities (#19314)

2026-03-05 18:30:52 +00:00

handlers

Limit outgoing to_device EDU size to 65536 (#18416)

2026-03-27 12:01:31 +00:00

http

Rename the test_disconnect test helper so that pytest doesn't see it as a test. (#19486)

2026-02-20 15:37:34 +00:00

logging

Port Clock functions to use Duration class (#19229)

2025-12-01 13:55:06 +00:00

media

Implement synapse issue #16751: Treat local_media_directory as optional storage provider (#19204)

2026-01-06 23:29:58 +00:00

metrics

Fix InFlightGauge typing to allow upgrading to prometheus_client 0.24 (#19379)

2026-01-16 20:35:30 +00:00

module_api

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

push

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

replication

Remove redacted_because from internal unsigned. (#19581)

2026-03-26 09:18:08 +00:00

rest

Limit outgoing to_device EDU size to 65536 (#18416)

2026-03-27 12:01:31 +00:00

scripts

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

server_notices

Port Clock functions to use Duration class (#19229)

2025-12-01 13:55:06 +00:00

state

Replace usage of deprecated assertEquals with assertEqual (#19345)

2026-01-06 17:30:21 +00:00

storage

Remove redacted_because from internal unsigned. (#19581)

2026-03-26 09:18:08 +00:00

synapse_rust

Simplify Rust HTTP client response streaming and limiting (#19510)

2026-03-03 15:24:25 +01:00

test_utils

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

types

Replace usage of deprecated assertEquals with assertEqual (#19345)

2026-01-06 17:30:21 +00:00

util

Allow long lived syncs to be cancelled if client has gone away (#19499)

2026-02-26 21:41:06 +00:00

__init__.py

Correctly mention previous copyright (#16820)

2024-01-23 11:26:48 +00:00

server.py

Allow Synapse to start up even when discovery fails for an OpenID Connect provider. (#19509)

2026-03-24 17:39:21 +00:00

test_distributor.py

Cleanly shutdown SynapseHomeServer object (#18828)

2025-10-01 02:42:09 +00:00

test_event_auth.py

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

test_mau.py

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

test_phone_home.py

Move unique snowflake homeserver background tasks to start_background_tasks (#19037)

2025-10-13 10:19:09 -05:00

test_rust.py

Add missing type hints to tests. (#15027)

2023-02-08 19:52:37 +00:00

test_server.py

Rename the test_disconnect test helper so that pytest doesn't see it as a test. (#19486)

2026-02-20 15:37:34 +00:00

test_state.py

Write union types as X | Y where possible (#19111)

2025-11-06 14:02:33 -06:00

test_terms_auth.py

Introduce Clock.call_when_running(...) to include logcontext by default (#18944)

2025-09-22 10:27:59 -05:00

test_types.py

Use type hinting generics in standard collections (#19046)

2025-10-22 16:48:19 -05:00

test_visibility.py

Transform events with client metadata before serialising in /event response. (#19340)

2026-01-06 15:53:13 +00:00

unittest.py

Demystify and deprecate HomeserverTestCase.pump() (Twisted reactor/clock) (#19602)

2026-03-25 15:33:17 -05:00

utils.py

Implement pagination for MSC2666 (#19279)

2025-12-16 15:24:36 +00:00