dendrite: Appservices/Bridges do not get events for random amounts of time

Background information

• Dendrite version or git SHA: 0.9.5
• Monolith or Polylith?: Monolith
• SQLite3 or Postgres?: Postgres
• Running in Docker?: yes
• go version: the one bundled with docker
• Client used (if applicable): Element but unrelated

Description

• What is the problem: Appservices/Bridges do not get events for random amounts of time
• Who is affected: Appservice/Bridge users
• How is this bug manifesting: I had 2 occurences, once events were not sent for 3h and once for 30mins, after that all events bursted into my bridges and got relayed, restarting did not help, db looked fine, logs looked fine, connection to appservices was working
• When did this first appear: 25 Aug /0.9.5 update

Steps to reproduce

• have appservices set up with dendrite (mautrix-facebook, mautrix-telegram, mautrix-signal)
• propably update to 0.9.5 from 0.9.4
• wait for seemingly random occurence

Unfortunatley after thorough investigation I could not find the cause nor a fix for this, everything looked normal, logs, database, logs of appservices/bridges, restarting does not fix the issue, restarted every docker container I had and it still persisted, this happened to another person in the matrix dendrite chat so this doesn’t look like a faulty setup to me but an issue with 0.95. Downgrading to 0.9.4 did not help tho.

On request I can provide full logs but there is nothing to see there according to my investigations.

Edit: Thanks to @mjohnson9 for coming up with a workaround (deleting the jetstream directory)