Commit Graph

171 Commits

Author SHA1 Message Date
Erik Johnston
76d21d14a0
Separate get_current_token into two. (#8113)
The function is used for two purposes: 1) for subscribers of streams to
get a token they can use to get further updates with, and 2) for
replication to track position of the writers of the stream.

For streams with a single writer the two scenarios produce the same
result, however the situation becomes complicated for streams with
multiple writers. The current `MultiWriterIdGenerator` does not
correctly handle the first case (which is not an issue as its only used
for the `caches` stream which nothing subscribes to outside of
replication).
2020-08-19 10:39:31 +01:00
David Vo
4dd27e6d11
Reduce unnecessary whitespace in JSON. (#7372) 2020-08-07 08:02:55 -04:00
Richard van der Hoff
f57b99af22
Handle replication commands synchronously where possible (#7876)
Most of the stuff we do for replication commands can be done synchronously. There's no point spinning up background processes if we're not going to need them.
2020-07-27 18:54:43 +01:00
Erik Johnston
84d099ae11
Fix typing replication not being handled on master (#7959)
Handling of incoming typing stream updates from replication was not
hooked up on master, effecting set ups where typing was handled on a
different worker.

This is really only a problem if the master process is also handling
sync requests, which is unlikely for those that are at the stage of
moving typing off.

The other observable effect is that if a worker restarts or a
replication connect drops then the typing worker will issue a
`POSITION typing`, triggering master process to try and stream *all*
typing updates from position 0.

Fixes #7907
2020-07-27 14:10:53 +01:00
Richard van der Hoff
931b026844
Remove an unused prometheus metric (#7878) 2020-07-22 00:40:55 +01:00
Richard van der Hoff
05060e0223
Track command processing as a background process (#7879)
I'm going to be doing more stuff synchronously, and I don't want to lose the
CPU metrics down the sofa.
2020-07-22 00:40:42 +01:00
Karthikeyan Singaravelan
a7b06a81f0
Fix deprecation warning: import ABC from collections.abc (#7892) 2020-07-20 13:33:04 -04:00
Richard van der Hoff
e5300063ed
Optimise queueing of inbound replication commands (#7861)
When we get behind on replication, we tend to stack up background processes
behind a linearizer. Bg processes are heavy (particularly with respect to
prometheus metrics) and linearizers aren't terribly efficient once the queue
gets long either.

A better approach is to maintain a queue of requests to be processed, and
nominate a single process to work its way through the queue.

Fixes: #7444
2020-07-16 15:49:37 +01:00
Erik Johnston
f2e38ca867
Allow moving typing off master (#7869) 2020-07-16 15:12:54 +01:00
Erik Johnston
f299441cc6
Add ability to shard the federation sender (#7798) 2020-07-10 18:26:36 +01:00
Patrick Cloke
38e1fac886
Fix some spelling mistakes / typos. (#7811) 2020-07-09 09:52:58 -04:00
Patrick Cloke
e7efd8f827
Do not use simplejson in Synapse. (#7800) 2020-07-08 07:15:08 -04:00
Erik Johnston
67d7756fcf
Refactor getting replication updates from database v2. (#7740) 2020-07-07 12:11:35 +01:00
Will Hunt
62b1ce8539
isort 5 compatibility (#7786)
The CI appears to use the latest version of isort, which is a problem when isort gets a major version bump. Rather than try to pin the version, I've done the necessary to make isort5 happy with synapse.
2020-07-05 16:32:02 +01:00
Erik Johnston
f6f7511a4c
Refactor getting replication updates from database. (#7636)
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.
2020-06-16 17:10:28 +01:00
Patrick Cloke
7d2532be36
Discard RDATA from already seen positions. (#7648) 2020-06-15 08:44:54 -04:00
Erik Johnston
664409b169
Fix bug in account data replication stream. (#7656)
* Ensure account data stream IDs are unique.

The account data stream is shared between three tables, and the maximum
allocated ID was tracked in a dedicated table. Updating the max ID
happened outside the transaction that allocated the ID, leading to a
race where if the server was restarted then the same ID could be
allocated but the max ID failed to be updated, leading it to be reused.

The ID generators have support for tracking across multiple tables, so
we may as well use that instead of a dedicated table.

* Fix bug in account data replication stream.

If the same stream ID was used in both global and room account data then
the getting updates for the replication stream would fail due to
`heapq.merge(..)` trying to compare a `str` with a `None`. (This is
because you'd have two rows like `(534, '!room')` and `(534, None)` from
the room and global account data tables).

Fix is just to order by stream ID, since we don't rely on the ordering
beyond that. The bug where stream IDs can be reused should be fixed now,
so this case shouldn't happen going forward.

Fixes #7617
2020-06-09 16:28:57 +01:00
Patrick Cloke
f1e61ef85c Typo fixes. 2020-06-05 08:43:21 -04:00
Erik Johnston
9bac5d62b3
Ensure ReplicationStreamer is always started when replication enabled. (#7579)
Fixes #7566.
2020-05-27 11:44:19 +01:00
Erik Johnston
e5c67d04db
Add option to move event persistence off master (#7517) 2020-05-22 16:11:35 +01:00
Erik Johnston
1531b214fc
Add ability to wait for replication streams (#7542)
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.
2020-05-22 14:21:54 +01:00
Richard van der Hoff
6c1f7c722f
Fix limit logic for AccountDataStream (#7384)
Make sure that the AccountDataStream presents complete updates, in the right
order.

This is much the same fix as #7337 and #7358, but applied to a different stream.
2020-05-15 19:03:25 +01:00
Erik Johnston
4734a7bbe4
Move EventStream handling into default ReplicationDataHandler (#7493)
This is so that the logic can happen on both master and workers when we move event persistence out.
2020-05-14 14:01:39 +01:00
Erik Johnston
7ee24c5674
Have all instances correctly respond to REPLICATE command. (#7475)
Before all streams were only written to from master, so only master needed to respond to `REPLICATE` commands.

Before all instances wrote to the cache invalidation stream, but didn't respond to `REPLICATE`. This was a bug, which could lead to missed rows from cache invalidation stream if an instance is restarted, however all the caches would be empty in that case so it wasn't a problem.
2020-05-13 10:27:02 +01:00
Erik Johnston
8ca79613e6
Fix Redis reconnection logic (#7482)
Proactively send out `POSITION` commands (as if we had just received a `REPLICATE`) when we connect to Redis. This is important as other instances won't notice we've connected to issue a `REPLICATE` command (unlike for direct TCP connections). This is only currently an issue if master process reconnects without restarting (if it restarts then it won't have written anything and so other instances probably won't have missed anything).
2020-05-13 09:57:15 +01:00
Andrew Morgan
5cf758cdd6 Merge branch 'release-v1.13.0' into develop
* release-v1.13.0:
  Don't UPGRADE database rows
  RST indenting
  Put rollback instructions in upgrade notes
  Fix changelog typo
  Oh yeah, RST
  Absolute URL it is then
  Fix upgrade notes link
  Provide summary of upgrade issues in changelog. Fix )
  Move next version notes from changelog to upgrade notes
  Changelog fixes
  1.13.0rc1
  Documentation on setting up redis (#7446)
  Rework UI Auth session validation for registration (#7455)
  Fix errors from malformed log line (#7454)
  Drop support for redis.dbid (#7450)
2020-05-11 16:46:33 +01:00
Richard van der Hoff
aa5aa6f96a
Fix errors from malformed log line (#7454) 2020-05-07 19:51:38 +01:00
Richard van der Hoff
da9b2db3af
Drop support for redis.dbid (#7450)
Since we only use pubsub, the dbid is irrelevant.
2020-05-07 16:46:15 +01:00
Erik Johnston
d7983b63a6
Support any process writing to cache invalidation stream. (#7436) 2020-05-07 13:51:08 +01:00
Richard van der Hoff
62ee862119 Merge branch 'release-v1.13.0' into develop 2020-05-06 15:56:03 +01:00
Richard van der Hoff
2e0c46ca07 Merge branch 'release-v1.13.0' into develop 2020-05-06 11:58:31 +01:00
Richard van der Hoff
a8c17da245 Merge branch 'release-v1.13.0' into rav/fix_dropped_messages 2020-05-05 23:01:12 +01:00
Richard van der Hoff
1242267316 Merge branch 'release-v1.13.0' into rav/fix_dropped_messages 2020-05-05 22:38:44 +01:00
Richard van der Hoff
7f7eedbebb Wait for a POSITION on the right connection before accepting RDATA
... otherwise we can believe we're up to date when we're not.
2020-05-05 22:38:16 +01:00
Brendan Abolivier
5b8023dc7f
Move logs about discarded RDATA to debug (#7421) 2020-05-05 21:07:33 +02:00
Richard van der Hoff
d78265af0c Wait to subscribe before sending REPLICATE 2020-05-05 19:31:37 +01:00
Richard van der Hoff
d5aa7d93ed
Fix catchup-on-reconnect for the Federation Stream (#7374)
looks like we managed to break this during the refactorathon.
2020-05-05 14:15:57 +01:00
Erik Johnston
350421e058
Fix redis password support. (#7401)
We forgot to set the password on the subscriber connection, as well as
not calling super methods for overridden connectionMade/connectionLost
functions.
2020-05-04 14:04:09 +01:00
Erik Johnston
0e719f2398
Thread through instance name to replication client. (#7369)
For in memory streams when fetching updates on workers we need to query the source of the stream, which currently is hard coded to be master. This PR threads through the source instance we received via `POSITION` through to the update function in each stream, which can then be passed to the replication client for in memory streams.
2020-05-01 17:19:56 +01:00
Erik Johnston
3085cde577
Use stream.current_token() and remove stream_positions() (#7172)
We move the processing of typing and federation replication traffic into their handlers so that `Stream.current_token()` points to a valid token. This allows us to remove `get_streams_to_replicate()` and `stream_positions()`.
2020-05-01 15:21:35 +01:00
Richard van der Hoff
b2dba06079
Workaround for assertion errors from db_query_to_update_function (#7378)
Hopefully this is no worse than what we have on master...
2020-05-01 09:25:16 +01:00
Erik Johnston
37f6823f5b
Add instance name to RDATA/POSITION commands (#7364)
This is primarily for allowing us to send those commands from workers, but for now simply allows us to ignore echoed RDATA/POSITION commands that we sent (we get echoes of sent commands when using redis). Currently we log a WARNING on the master process every time we receive an echoed RDATA.
2020-04-29 16:23:08 +01:00
Erik Johnston
3eab76ad43
Don't relay REMOTE_SERVER_UP cmds to same conn. (#7352)
For direct TCP connections we need the master to relay REMOTE_SERVER_UP
commands to the other connections so that all instances get notified
about it. The old implementation just relayed to all connections,
assuming that sending back to the original sender of the command was
safe. This is not true for redis, where commands sent get echoed back to
the sender, which was causing master to effectively infinite loop
sending and then re-receiving REMOTE_SERVER_UP commands that it sent.

The fix is to ensure that we only relay to *other* connections and not
to the connection we received the notification from.

Fixes #7334.
2020-04-29 14:10:59 +01:00
Richard van der Hoff
c2e1a2110f
Fix limit logic for EventsStream (#7358)
* Factor out functions for injecting events into database

I want to add some more flexibility to the tools for injecting events into the
database, and I don't want to clutter up HomeserverTestCase with them, so let's
factor them out to a new file.

* Rework TestReplicationDataHandler

This wasn't very easy to work with: the mock wrapping was largely superfluous,
and it's useful to be able to inspect the received rows, and clear out the
received list.

* Fix AssertionErrors being thrown by EventsStream

Part of the problem was that there was an off-by-one error in the assertion,
but also the limit logic was too simple. Fix it all up and add some tests.
2020-04-29 12:30:36 +01:00
Erik Johnston
38919b521e
Run replication streamers on workers (#7146)
Currently we never write to streams from workers, but that will change soon
2020-04-28 13:34:12 +01:00
Richard van der Hoff
ce428a1abe Fix EventsStream raising assertions when it falls behind
Figuring out how to correctly limit updates from this stream without dropping
entries is far more complicated than just counting the number of rows being
returned. We need to consider each query separately and, if any one query hits
the limit, truncate the results from the others.

I think this also fixes some potentially long-standing bugs where events or
state changes could get missed if we hit the limit on either query.
2020-04-24 13:59:21 +01:00
Richard van der Hoff
9cbdfb3a2f Make it clear that the limit for an update_function is a target 2020-04-23 15:45:12 +01:00
Richard van der Hoff
23b28266ac Remove 'limit' param from get_repl_stream_updates API
there doesn't seem to be much point in passing this limit all around, since
both sides agree it's meant to be 100.
2020-04-23 15:44:35 +01:00
Richard van der Hoff
71a1abb8a1
Stop the master relaying USER_SYNC for other workers (#7318)
Long story short: if we're handling presence on the current worker, we shouldn't be sending USER_SYNC commands over replication.

In an attempt to figure out what is going on here, I ended up refactoring some bits of the presencehandler code, so the first 4 commits here are non-functional refactors to move this code slightly closer to sanity. (There's still plenty to do here :/). Suggest reviewing individual commits.

Fixes (I hope) #7257.
2020-04-22 22:39:04 +01:00
Erik Johnston
841c581c40
Fix replication metrics when using redis (#7325) 2020-04-22 16:26:19 +01:00