The previous version was getting **ALL** membership events (as
`ClientEvents`, so going through `NewEventFromTrustedJSONWithID`) for a
given room.
Now we are querying only locally joined users as `ClientEvents`, which
should **significantly** reduce allocations.
Take for example a large room with 2k membership events, but only 1
local user - avoiding 1999 `NewEventFromTrustedJSONWithID` calls just to
calculate the `roomSize` which we can also query by other means.
This is also getting called for every `OutputRoomEvent` in the userAPI.
Benchmark with 1 local user and 100 remote users.
```
pkg: github.com/matrix-org/dendrite/userapi/consumers
cpu: 12th Gen Intel(R) Core(TM) i5-12500H
│ old.txt │ new.txt │
│ sec/op │ sec/op vs base │
LocalRoomMembers-16 375.9µ ± 7% 327.6µ ± 6% -12.85% (p=0.000 n=10)
│ old.txt │ new.txt │
│ B/op │ B/op vs base │
LocalRoomMembers-16 79.426Ki ± 0% 8.507Ki ± 0% -89.29% (p=0.000 n=10)
│ old.txt │ new.txt │
│ allocs/op │ allocs/op vs base │
LocalRoomMembers-16 1015.0 ± 0% 277.0 ± 0% -72.71% (p=0.000 n=10)
```
When we're adding state to the database, we check which eventNIDs are
already in a block, if we already have that eventNID, we remove it from
the list. In its current form we would skip over eventNIDs in the case
we already found a match (we're decrementing `i` twice)
My theory is, that when we later get the state blocks, we are receiving
"too many" eventNIDs (well, yea, we stored too many), which may or may
not can result in state resets when comparing different state snapshots.
(e.g. when adding state we stored a eventNID by accident because we
skipped it, later we add more state and are not adding it because we
don't skip it)
This should fix two issues with backfilling:
1. right after creating and joining a room over federation, we are doing
a `/backfill` request, which would return redacted events, because the
`authEvents` are empty. Even though the spec states that, in the absence
of a history visibility event, it should be handled as `shared`.
2. `gomatrixserverlib: unsupported room version ''` - because, well, we
were never setting the `roomInfo` field..
They are fundamentally different concepts, so should be represented as
such. Proto events are exchanged in /make_xxx calls over federation, and
made as "fledgling" events in /createRoom and general event sending.
*Building* events is a reasonably complex VERSION SPECIFIC process which
needs amongst other things, auth event providers, prev events, signing
keys, etc.
Requires https://github.com/matrix-org/gomatrixserverlib/pull/379
Requires https://github.com/matrix-org/gomatrixserverlib/pull/376
This has numerous upsides:
- Less type casting to `*Event` is required.
- Making Dendrite work with `PDU` interfaces means we can swap out Event
impls more easily.
- Tests which represent weird event shapes are easier to write.
Part of a series of refactors on GMSL.
