We have seen a failure mode here where if there are many in flight
unfinished IDs then marking an ID as finished takes a lot of CPU (as
calling deque.remove iterates over the list)
Introduced in #9104
This wasn't picked up by the tests as this is all fine the first time you run Synapse (after upgrading), but then when you restart the wrong value is pulled from `stream_positions`.
We do this by allowing a single iteration to process multiple rooms at a
time, as there are often a lot of really tiny rooms, which can massively
slow things down.
You can't continue using a transaction once an exception has been
raised, so catching and dropping the error here is pointless and just
causes more errors.
It's important that we make sure our background updates happen in a defined
order, to avoid disasters like #6923.
Add an ordering to all of the background updates that have landed since #7190.
This is another PR that grew out of #6739.
The existing code for checking whether a user is currently invited to a room when they want to leave the room looks like the following:
f737368a26/synapse/handlers/room_member.py (L518-L540)
It calls `get_invite_for_local_user_in_room`, which will actually query *all* rooms the user has been invited to, before iterating over them and matching via the room ID. It will then return a tuple of a lot of information which we pull the event ID out of.
I need to do a similar check for knocking, but this code wasn't very efficient. I then tried to write a different implementation using `StateHandler.get_current_state` but this actually didn't work as we haven't *joined* the room yet - we've only been invited to it. That means that only certain tables in Synapse have our desired `invite` membership state. One of those tables is `local_current_membership`.
So I wrote a store method that just queries that table instead
* Make this line debug (it's noisy)
* Don't include from_key for presence if we are at 0
* Limit read receipts for all rooms to 100
* changelog.d/8744.bugfix
* Allow from_key to be None
* Update 8744.bugfix
* The from_key is superflous
* Update comment
There's a handy function called maybe_store_room_on_invite which allows us to create an entry in the rooms table for a room and its version for which we aren't joined to yet, but we can reference when ingesting events about.
This is currently used for invites where we receive some stripped state about the room and pass it down via /sync to the client, without us being in the room yet.
There is a similar requirement for knocking, where we will eventually do the same thing, and need an entry in the rooms table as well. Thus, reusing this function works, however its name needs to be generalised a bit.
Separated out from #6739.
Erik Johnston