Benoit Marty d59120aad0 Restart the sync service when it stops on an error ...

Synapse deletes sliding sync connections that have been unused for 7 days. When
an OEM battery manager has kept the application frozen for longer than that, the
next sliding sync request is answered 400 M_UNKNOWN_POS.

The Rust SDK handles that: it resets `pos` and, in offline mode, restarts the
sync. When that recovery gives up, the sync service ends up in the Error or
Terminated state and stops for good, and it is then up to the application to
call start() again. Element X iOS does it, we do not: SyncOrchestrator only
restarts the sync service when its state is Idle, so the sync stays dead for the
rest of the process lifetime.

Nothing recovers from there. The sync never reaches Running, so
waitForE2eeInitializationTasks() never returns, the session verified status
stays Unknown, and the FTUE is stuck on WaitingForInitialState. Clearing the
application data is the only workaround.

Restart the sync service when it is in the Error or Terminated state, with an
exponential backoff from 1s to 30s to avoid hammering a failing homeserver. The
backoff is only reset once the sync service has been running for a while, since
startSync() moves the state to Running right away.

Fixes #7689

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

2026-09-11 12:48:58 +02:00

..

src

Restart the sync service when it stops on an error

2026-09-11 12:48:58 +02:00

build.gradle.kts

Move FakeCacheService to the preferences test module

2026-08-20 15:17:18 +02:00