This makes the serialization of events synchronous (and it no
longer access the database), but we must manually calculate and
provide the bundled aggregations.
Overall this should cause no change in behavior, but is prep work
for other improvements.
* Wrap `auth.get_user_by_req` in an opentracing span
give `get_user_by_req` its own opentracing span, since it can result in a
non-trivial number of sub-spans which it is useful to group together.
This requires a bit of reorganisation because it also sets some tags (and may
force tracing) on the servlet span.
* Emit opentracing span for encoding json responses
This can be a significant time sink.
* Rename all sync spans with a prefix
* Write an opentracing span for encoding sync response
* opentracing span to group generate_room_entries
* opentracing spans within sync.encode_response
* changelog
* Use the `trace` decorator instead of context managers
* Disable aggregation bundling on `/sync` responses
A partial revert of #11478. This turns out to have had a significant CPU impact
on initial-sync handling. For now, let's disable it, until we find a more
efficient way of achieving this.
* Fix tests.
Co-authored-by: Patrick Cloke <patrickc@matrix.org>
Due to updates to MSC2675 this includes a few fixes:
* Include bundled aggregations for /sync.
* Do not include bundled aggregations for /initialSync and /events.
* Do not bundle aggregations for state events.
* Clarifies comments and variable names.
