Currently when fetching state groups from the data store we make two
hits two the database: once for members and once for non-members (unless
request is filtered to one or the other). This adds needless load to the
datbase, so this PR refactors the lookup to make only a single database
hit.
In particular, we assume that the name and canonical alias events in
the state have not been rejected. In practice this may not be the case
(though we should probably think about fixing that) so lets ensure that
we gracefully handle that case, rather than 404'ing the sync request
like we do now.
Given we have disabled lazy loading for incr syncs in #3840, we can make self-LL more efficient by only doing it on initial sync. Also adds a bounds check for if/when we change our mind, so that we don't try to include LL members on sync responses with no timeline.
* speed up room summaries by pulling their data from room_memberships rather than room state
* disable LL for incr syncs, and log incr sync stats (#3840)
When a user joined a room any existing tags were not sent down the sync
stream. Ordinarily this isn't a problem because the user needs to be in
the room to have set tags in it, however synapse will sometimes add tags
for a user to a room, e.g. for server notices, which need to come down
sync.
* attempt at deduplicating lazy-loaded members
as per the proposal; we can deduplicate redundant lazy-loaded members
which are sent in the same sync sequence. we do this heuristically
rather than requiring the client to somehow tell us which members it
has chosen to cache, by instead caching the last N members sent to
a client, and not sending them again. For now we hardcode N to 100.
Each cache for a given (user,device) tuple is in turn cached for up to
X minutes (to avoid the caches building up). For now we hardcode X to 30.
* add include_redundant_members filter option & make it work
* remove stale todo
* add tests for _get_some_state_from_cache
* incorporate review
Previously we only queried the device list when the user joined the room; now we
do it when they are invited too. This means that new messages can be encrypted
for the devices of the invited user as of the point they were invited.
WARNING: This commit has two major problems however:
1. If the invited user adds devices after being invited but before joining, the
device-list will not be updated to the other servers in the room (as we don't
know who those servers are).
2. This introduces a regression, as previously the device-list would be correctly
updated when when user joined the room. However, this resync doesn't happen
now, so devices which joined after the invite and before the join may never
be added to the device-list.
This is being merged for DINSIC given the edge case of adding devices between
invite & join is pretty rare in their use case, but before it can be merged to
synapse in general we need to at least re-sync the devicelist when the user joins
or to implement some kind of pubsub mechanism to let interested servers subscribe
to devicelist updates on other servers irrespective of user join/invite membership.
This was originally https://github.com/matrix-org/synapse/pull/3484
The sync API often returns events in a topological rather than stream
ordering, e.g. when the user joined the room or on initial sync. When
this happens we can reuse existing pagination storage functions.
