def __init__(
self,
database: DatabasePool,
db_conn: LoggingDatabaseConnection,
hs: "HomeServer",
):
self.services_cache = load_appservices(
hs.hostname, hs.config.appservice.app_service_config_files)
self.exclusive_user_regex = _make_exclusive_regex(self.services_cache)
def get_max_as_txn_id(txn: Cursor) -> int:
logger.warning(
"Falling back to slow query, you should port to postgres")
txn.execute(
"SELECT COALESCE(max(txn_id), 0) FROM application_services_txns"
)
return cast(Tuple[int], txn.fetchone())[0]
self._as_txn_seq_gen = build_sequence_generator(
db_conn,
database.engine,
get_max_as_txn_id,
"application_services_txn_id_seq",
table="application_services_txns",
id_column="txn_id",
)
super().__init__(database, db_conn, hs)
def __init__(self, database: DatabasePool, db_conn, hs):
super().__init__(database, db_conn, hs)
# Originally the state store used a single DictionaryCache to cache the
# event IDs for the state types in a given state group to avoid hammering
# on the state_group* tables.
#
# The point of using a DictionaryCache is that it can cache a subset
# of the state events for a given state group (i.e. a subset of the keys for a
# given dict which is an entry in the cache for a given state group ID).
#
# However, this poses problems when performing complicated queries
# on the store - for instance: "give me all the state for this group, but
# limit members to this subset of users", as DictionaryCache's API isn't
# rich enough to say "please cache any of these fields, apart from this subset".
# This is problematic when lazy loading members, which requires this behaviour,
# as without it the cache has no choice but to speculatively load all
# state events for the group, which negates the efficiency being sought.
#
# Rather than overcomplicating DictionaryCache's API, we instead split the
# state_group_cache into two halves - one for tracking non-member events,
# and the other for tracking member_events. This means that lazy loading
# queries can be made in a cache-friendly manner by querying both caches
# separately and then merging the result. So for the example above, you
# would query the members cache for a specific subset of state keys
# (which DictionaryCache will handle efficiently and fine) and the non-members
# cache for all state (which DictionaryCache will similarly handle fine)
# and then just merge the results together.
#
# We size the non-members cache to be smaller than the members cache as the
# vast majority of state in Matrix (today) is member events.
self._state_group_cache = DictionaryCache(
"*stateGroupCache*",
# TODO: this hasn't been tuned yet
50000,
)
self._state_group_members_cache = DictionaryCache(
"*stateGroupMembersCache*",
500000,
)
def get_max_state_group_txn(txn: Cursor):
txn.execute("SELECT COALESCE(max(id), 0) FROM state_groups")
return txn.fetchone()[0]
self._state_group_seq_gen = build_sequence_generator(
db_conn,
self.database_engine,
get_max_state_group_txn,
"state_group_id_seq",
table="state_groups",
id_column="id",
)
