Some useful SQL queries for Synapse Admins
Size of full matrix db
SELECT pg_size_pretty( pg_database_size( 'matrix' ) );
Result example:
pg_size_pretty
----------------
6420 MB
(1 row)
Show top 20 larger tables by row count
SELECT relname, n_live_tup AS "rows"
FROM pg_stat_user_tables
ORDER BY n_live_tup DESC
LIMIT 20;
This query is quick, but may be very approximate, for exact number of rows use:
SELECT COUNT(*) FROM <table_name>;
Result example:
state_groups_state - 161687170
event_auth - 8584785
event_edges - 6995633
event_json - 6585916
event_reference_hashes - 6580990
events - 6578879
received_transactions - 5713989
event_to_state_groups - 4873377
stream_ordering_to_exterm - 4136285
current_state_delta_stream - 3770972
event_search - 3670521
state_events - 2845082
room_memberships - 2785854
cache_invalidation_stream - 2448218
state_groups - 1255467
state_group_edges - 1229849
current_state_events - 1222905
users_in_public_rooms - 364059
device_lists_stream - 326903
user_directory_search - 316433
Show top 20 larger tables by storage size
SELECT nspname || '.' || relname AS "relation",
pg_size_pretty(pg_total_relation_size(c.oid)) AS "total_size"
FROM pg_class c
LEFT JOIN pg_namespace n ON (n.oid = c.relnamespace)
WHERE nspname NOT IN ('pg_catalog', 'information_schema')
AND c.relkind <> 'i'
AND nspname !~ '^pg_toast'
ORDER BY pg_total_relation_size(c.oid) DESC
LIMIT 20;
Result example:
public.state_groups_state - 27 GB
public.event_json - 9855 MB
public.events - 3675 MB
public.event_edges - 3404 MB
public.received_transactions - 2745 MB
public.event_reference_hashes - 1864 MB
public.event_auth - 1775 MB
public.stream_ordering_to_exterm - 1663 MB
public.event_search - 1370 MB
public.room_memberships - 1050 MB
public.event_to_state_groups - 948 MB
public.current_state_delta_stream - 711 MB
public.state_events - 611 MB
public.presence_stream - 530 MB
public.current_state_events - 525 MB
public.cache_invalidation_stream - 466 MB
public.receipts_linearized - 279 MB
public.state_groups - 160 MB
public.device_lists_remote_cache - 124 MB
public.state_group_edges - 122 MB
Show top 20 larger rooms by state events count
You get the same information when you use the
admin API
and set parameter order_by=state_events.
SELECT r.name, s.room_id, s.current_state_events
FROM room_stats_current s
LEFT JOIN room_stats_state r USING (room_id)
ORDER BY current_state_events DESC
LIMIT 20;
and by state_group_events count:
SELECT rss.name, s.room_id, COUNT(s.room_id)
FROM state_groups_state s
LEFT JOIN room_stats_state rss USING (room_id)
GROUP BY s.room_id, rss.name
ORDER BY COUNT(s.room_id) DESC
LIMIT 20;
plus same, but with join removed for performance reasons:
SELECT s.room_id, COUNT(s.room_id)
FROM state_groups_state s
GROUP BY s.room_id
ORDER BY COUNT(s.room_id) DESC
LIMIT 20;
Show top 20 rooms by new events count in last 1 day:
SELECT e.room_id, r.name, COUNT(e.event_id) cnt
FROM events e
LEFT JOIN room_stats_state r USING (room_id)
WHERE e.origin_server_ts >= DATE_PART('epoch', NOW() - INTERVAL '1 day') * 1000
GROUP BY e.room_id, r.name
ORDER BY cnt DESC
LIMIT 20;
Show top 20 users on homeserver by sent events (messages) at last month:
Caution. This query does not use any indexes, can be slow and create load on the database.
SELECT COUNT(*), sender
FROM events
WHERE (type = 'm.room.encrypted' OR type = 'm.room.message')
AND origin_server_ts >= DATE_PART('epoch', NOW() - INTERVAL '1 month') * 1000
GROUP BY sender
ORDER BY COUNT(*) DESC
LIMIT 20;
Show last 100 messages from needed user, with room names:
SELECT e.room_id, r.name, e.event_id, e.type, e.content, j.json
FROM events e
LEFT JOIN event_json j USING (room_id)
LEFT JOIN room_stats_state r USING (room_id)
WHERE sender = '@LOGIN:example.com'
AND e.type = 'm.room.message'
ORDER BY stream_ordering DESC
LIMIT 100;
Show rooms with names, sorted by events in this rooms
Sort and order with bash
echo "SELECT event_json.room_id, room_stats_state.name FROM event_json, room_stats_state \
WHERE room_stats_state.room_id = event_json.room_id" | psql -d synapse -h localhost -U synapse_user -t \
| sort | uniq -c | sort -n
Documentation for psql command line parameters: https://www.postgresql.org/docs/current/app-psql.html
Sort and order with SQL
SELECT COUNT(*), event_json.room_id, room_stats_state.name
FROM event_json, room_stats_state
WHERE room_stats_state.room_id = event_json.room_id
GROUP BY event_json.room_id, room_stats_state.name
ORDER BY COUNT(*) DESC
LIMIT 50;
Result example:
9459 !FPUfgzXYWTKgIrwKxW:matrix.org | This Week in Matrix
9459 !FPUfgzXYWTKgIrwKxW:matrix.org | This Week in Matrix (TWIM)
17799 !iDIOImbmXxwNngznsa:matrix.org | Linux in Russian
18739 !GnEEPYXUhoaHbkFBNX:matrix.org | Riot Android
23373 !QtykxKocfZaZOUrTwp:matrix.org | Matrix HQ
39504 !gTQfWzbYncrtNrvEkB:matrix.org | ru.[matrix]
43601 !iNmaIQExDMeqdITdHH:matrix.org | Riot
43601 !iNmaIQExDMeqdITdHH:matrix.org | Riot Web/Desktop
Lookup room state info by list of room_id
You get the same information when you use the admin API.
SELECT rss.room_id, rss.name, rss.canonical_alias, rss.topic, rss.encryption,
rsc.joined_members, rsc.local_users_in_room, rss.join_rules
FROM room_stats_state rss
LEFT JOIN room_stats_current rsc USING (room_id)
WHERE room_id IN (
'!OGEhHVWSdvArJzumhm:matrix.org',
'!YTvKGNlinIzlkMTVRl:matrix.org'
);
Show users and devices that have not been online for a while
SELECT user_id, device_id, user_agent, TO_TIMESTAMP(last_seen / 1000) AS "last_seen"
FROM devices
WHERE last_seen < DATE_PART('epoch', NOW() - INTERVAL '3 month') * 1000;
Clear the cache of a remote user's device list
Forces the resync of a remote user's device list - if you have somehow cached a bad state, and the remote server is will not send out a device list update.
INSERT INTO device_lists_remote_resync
VALUES ('USER_ID', (EXTRACT(epoch FROM NOW()) * 1000)::BIGINT);