dendrite: Monolithic server client API becomes unresponsive until restarted

Background information

• Dendrite version or git SHA: bca2790c678887232266c5726be79b80ddd9930b (post-dev v0.3.4 for https://github.com/matrix-org/dendrite/pull/1672)
• Monolith or Polylith?: Monolith
• SQLite3 or Postgres?: Postgres
• Running in Docker?: Docker
• go version: official images

Description

My Dendrite server has become unresponsive two times in a 24 hour period. This is noticed by Element web (app.element.io) saying the server is offline. The console logs show sync endpoints timing out.

Restarting the docker container has caused the issue to resolve on both times.

Nothing interesting found in logs that I could spot, errors mainly related to fetching of remote auth events. Will submit a log file privately that covers the second time with an issue.

Dendrite is v0.3.4 post dev on hash bca2790c678887232266c5726be79b80ddd9930b (which is a part of https://github.com/matrix-org/dendrite/pull/1672). MSC2836 is enabled in settings.

While the unresponsiveness continues, the logs do show activity in the federation API’s.