State res v2 across large data sets can be very CPU intensive, and if
all the relevant events are in the cache the algorithm will run from
start to finish within a single reactor tick. This can result in
blocking the reactor tick for several seconds, which can have major
repercussions on other requests.
To fix this we simply add the occaisonal `sleep(0)` during iterations to
yield execution until the next reactor tick. The aim is to only do this
for large data sets so that we don't impact otherwise quick resolutions.=
The aim here is to make it easier to reason about when streams are limited and when they're not, by moving the logic into the database functions themselves. This should mean we can kill of `db_query_to_update_function` function.
Fixes https://github.com/matrix-org/synapse/issues/2431
Adds config option `encryption_enabled_by_default_for_room_type`, which determines whether encryption should be enabled with the default encryption algorithm in private or public rooms upon creation. Whether the room is private or public is decided based upon the room creation preset that is used.
Part of this PR is also pulling out all of the individual instances of `m.megolm.v1.aes-sha2` into a constant variable to eliminate typos ala https://github.com/matrix-org/synapse/pull/7637
Based on #7637
While working on https://github.com/matrix-org/synapse/issues/5665 I found myself digging into the `Ratelimiter` class and seeing that it was both:
* Rather undocumented, and
* causing a *lot* of config checks
This PR attempts to refactor and comment the `Ratelimiter` class, as well as encourage config file accesses to only be done at instantiation.
Best to be reviewed commit-by-commit.
* Expose `return_html_error`, and allow it to take a Jinja2 template instead of a raw string
* Clean up exception handling in SAML2ResponseResource
* use the existing code in `return_html_error` instead of re-implementing it
(giving it a jinja2 template rather than inventing a new form of template)
* do the exception-catching in the REST layer rather than in the handler
layer, to make sure we catch all exceptions.
It looks like `user_device_resync` was ignoring cross-signing keys from the results received from the remote server. This patch fixes this, by processing these keys using the same process `_handle_signing_key_updates` does (and effectively factor that part out of that function).
Without this patch, if an error happens which isn't caught by `user_device_resync`, then `_maybe_retry_device_resync` would fail, without retrying the next users in the iteration. This patch fixes this so that it now only logs an error in this case.
The idea here is that if an instance persists an event via the replication HTTP API it can return before we receive that event over replication, which can lead to races where code assumes that persisting an event immediately updates various caches (e.g. current state of the room).
Most of Synapse doesn't hit such races, so we don't do the waiting automagically, instead we do so where necessary to avoid unnecessary delays. We may decide to change our minds here if it turns out there are a lot of subtle races going on.
People probably want to look at this commit by commit.
Instead of doing a complicated dance of deleting and moving aliases one
by one, which sends a canonical alias update into the old room for each
one, lets do it all in one go.
This also changes the function to move *all* local alias events to the new
room, however that happens later on anyway.
When a call to `user_device_resync` fails, we don't currently mark the remote user's device list as out of sync, nor do we retry to sync it.
https://github.com/matrix-org/synapse/pull/6776 introduced some code infrastructure to mark device lists as stale/out of sync.
This commit uses that code infrastructure to mark device lists as out of sync if processing an incoming device list update makes the device handler realise that the device list is out of sync, but we can't resync right now.
It also adds a looping call to retry all failed resync every 30s. This shouldn't cause too much spam in the logs as this commit also removes the "Failed to handle device list update for..." warning logs when catching `NotRetryingDestination`.
Fixes#7418
