Move state's bg updates to a dedicated store

This commit is contained in:
Brendan Abolivier 2019-10-03 17:56:16 +01:00
parent 841054ad96
commit cfccd2d78a

View file

@ -353,8 +353,158 @@ class StateFilter(object):
return member_filter, non_member_filter
class StateGroupBackgroundUpdateStore(SQLBaseStore):
"""Defines functions related to state groups needed to run the state backgroud
updates.
"""
def _count_state_group_hops_txn(self, txn, state_group):
"""Given a state group, count how many hops there are in the tree.
This is used to ensure the delta chains don't get too long.
"""
if isinstance(self.database_engine, PostgresEngine):
sql = """
WITH RECURSIVE state(state_group) AS (
VALUES(?::bigint)
UNION ALL
SELECT prev_state_group FROM state_group_edges e, state s
WHERE s.state_group = e.state_group
)
SELECT count(*) FROM state;
"""
txn.execute(sql, (state_group,))
row = txn.fetchone()
if row and row[0]:
return row[0]
else:
return 0
else:
# We don't use WITH RECURSIVE on sqlite3 as there are distributions
# that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
next_group = state_group
count = 0
while next_group:
next_group = self._simple_select_one_onecol_txn(
txn,
table="state_group_edges",
keyvalues={"state_group": next_group},
retcol="prev_state_group",
allow_none=True,
)
if next_group:
count += 1
return count
def _get_state_groups_from_groups_txn(
self, txn, groups, state_filter=StateFilter.all()
):
results = {group: {} for group in groups}
where_clause, where_args = state_filter.make_sql_filter_clause()
# Unless the filter clause is empty, we're going to append it after an
# existing where clause
if where_clause:
where_clause = " AND (%s)" % (where_clause,)
if isinstance(self.database_engine, PostgresEngine):
# Temporarily disable sequential scans in this transaction. This is
# a temporary hack until we can add the right indices in
txn.execute("SET LOCAL enable_seqscan=off")
# The below query walks the state_group tree so that the "state"
# table includes all state_groups in the tree. It then joins
# against `state_groups_state` to fetch the latest state.
# It assumes that previous state groups are always numerically
# lesser.
# The PARTITION is used to get the event_id in the greatest state
# group for the given type, state_key.
# This may return multiple rows per (type, state_key), but last_value
# should be the same.
sql = """
WITH RECURSIVE state(state_group) AS (
VALUES(?::bigint)
UNION ALL
SELECT prev_state_group FROM state_group_edges e, state s
WHERE s.state_group = e.state_group
)
SELECT DISTINCT type, state_key, last_value(event_id) OVER (
PARTITION BY type, state_key ORDER BY state_group ASC
ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING
) AS event_id FROM state_groups_state
WHERE state_group IN (
SELECT state_group FROM state
)
"""
for group in groups:
args = [group]
args.extend(where_args)
txn.execute(sql + where_clause, args)
for row in txn:
typ, state_key, event_id = row
key = (typ, state_key)
results[group][key] = event_id
else:
max_entries_returned = state_filter.max_entries_returned()
# We don't use WITH RECURSIVE on sqlite3 as there are distributions
# that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
for group in groups:
next_group = group
while next_group:
# We did this before by getting the list of group ids, and
# then passing that list to sqlite to get latest event for
# each (type, state_key). However, that was terribly slow
# without the right indices (which we can't add until
# after we finish deduping state, which requires this func)
args = [next_group]
args.extend(where_args)
txn.execute(
"SELECT type, state_key, event_id FROM state_groups_state"
" WHERE state_group = ? " + where_clause,
args,
)
results[group].update(
((typ, state_key), event_id)
for typ, state_key, event_id in txn
if (typ, state_key) not in results[group]
)
# If the number of entries in the (type,state_key)->event_id dict
# matches the number of (type,state_keys) types we were searching
# for, then we must have found them all, so no need to go walk
# further down the tree... UNLESS our types filter contained
# wildcards (i.e. Nones) in which case we have to do an exhaustive
# search
if (
max_entries_returned is not None
and len(results[group]) == max_entries_returned
):
break
next_group = self._simple_select_one_onecol_txn(
txn,
table="state_group_edges",
keyvalues={"state_group": next_group},
retcol="prev_state_group",
allow_none=True,
)
return results
# this inherits from EventsWorkerStore because it calls self.get_events
class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
class StateGroupWorkerStore(
EventsWorkerStore, StateGroupBackgroundUpdateStore, SQLBaseStore
):
"""The parts of StateGroupStore that can be called from workers.
"""
@ -694,107 +844,6 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
return results
def _get_state_groups_from_groups_txn(
self, txn, groups, state_filter=StateFilter.all()
):
results = {group: {} for group in groups}
where_clause, where_args = state_filter.make_sql_filter_clause()
# Unless the filter clause is empty, we're going to append it after an
# existing where clause
if where_clause:
where_clause = " AND (%s)" % (where_clause,)
if isinstance(self.database_engine, PostgresEngine):
# Temporarily disable sequential scans in this transaction. This is
# a temporary hack until we can add the right indices in
txn.execute("SET LOCAL enable_seqscan=off")
# The below query walks the state_group tree so that the "state"
# table includes all state_groups in the tree. It then joins
# against `state_groups_state` to fetch the latest state.
# It assumes that previous state groups are always numerically
# lesser.
# The PARTITION is used to get the event_id in the greatest state
# group for the given type, state_key.
# This may return multiple rows per (type, state_key), but last_value
# should be the same.
sql = """
WITH RECURSIVE state(state_group) AS (
VALUES(?::bigint)
UNION ALL
SELECT prev_state_group FROM state_group_edges e, state s
WHERE s.state_group = e.state_group
)
SELECT DISTINCT type, state_key, last_value(event_id) OVER (
PARTITION BY type, state_key ORDER BY state_group ASC
ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING
) AS event_id FROM state_groups_state
WHERE state_group IN (
SELECT state_group FROM state
)
"""
for group in groups:
args = [group]
args.extend(where_args)
txn.execute(sql + where_clause, args)
for row in txn:
typ, state_key, event_id = row
key = (typ, state_key)
results[group][key] = event_id
else:
max_entries_returned = state_filter.max_entries_returned()
# We don't use WITH RECURSIVE on sqlite3 as there are distributions
# that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
for group in groups:
next_group = group
while next_group:
# We did this before by getting the list of group ids, and
# then passing that list to sqlite to get latest event for
# each (type, state_key). However, that was terribly slow
# without the right indices (which we can't add until
# after we finish deduping state, which requires this func)
args = [next_group]
args.extend(where_args)
txn.execute(
"SELECT type, state_key, event_id FROM state_groups_state"
" WHERE state_group = ? " + where_clause,
args,
)
results[group].update(
((typ, state_key), event_id)
for typ, state_key, event_id in txn
if (typ, state_key) not in results[group]
)
# If the number of entries in the (type,state_key)->event_id dict
# matches the number of (type,state_keys) types we were searching
# for, then we must have found them all, so no need to go walk
# further down the tree... UNLESS our types filter contained
# wildcards (i.e. Nones) in which case we have to do an exhaustive
# search
if (
max_entries_returned is not None
and len(results[group]) == max_entries_returned
):
break
next_group = self._simple_select_one_onecol_txn(
txn,
table="state_group_edges",
keyvalues={"state_group": next_group},
retcol="prev_state_group",
allow_none=True,
)
return results
@defer.inlineCallbacks
def get_state_for_events(self, event_ids, state_filter=StateFilter.all()):
"""Given a list of event_ids and type tuples, return a list of state
@ -1238,66 +1287,8 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
return self.runInteraction("store_state_group", _store_state_group_txn)
def _count_state_group_hops_txn(self, txn, state_group):
"""Given a state group, count how many hops there are in the tree.
This is used to ensure the delta chains don't get too long.
"""
if isinstance(self.database_engine, PostgresEngine):
sql = """
WITH RECURSIVE state(state_group) AS (
VALUES(?::bigint)
UNION ALL
SELECT prev_state_group FROM state_group_edges e, state s
WHERE s.state_group = e.state_group
)
SELECT count(*) FROM state;
"""
txn.execute(sql, (state_group,))
row = txn.fetchone()
if row and row[0]:
return row[0]
else:
return 0
else:
# We don't use WITH RECURSIVE on sqlite3 as there are distributions
# that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
next_group = state_group
count = 0
while next_group:
next_group = self._simple_select_one_onecol_txn(
txn,
table="state_group_edges",
keyvalues={"state_group": next_group},
retcol="prev_state_group",
allow_none=True,
)
if next_group:
count += 1
return count
class StateStore(StateGroupWorkerStore, BackgroundUpdateStore):
""" Keeps track of the state at a given event.
This is done by the concept of `state groups`. Every event is a assigned
a state group (identified by an arbitrary string), which references a
collection of state events. The current state of an event is then the
collection of state events referenced by the event's state group.
Hence, every change in the current state causes a new state group to be
generated. However, if no change happens (e.g., if we get a message event
with only one parent it inherits the state group from its parent.)
There are three tables:
* `state_groups`: Stores group name, first event with in the group and
room id.
* `event_to_state_groups`: Maps events to state groups.
* `state_groups_state`: Maps state group to state events.
"""
class StateBackgroundUpdateStore(StateGroupBackgroundUpdateStore, BackgroundUpdateStore):
STATE_GROUP_DEDUPLICATION_UPDATE_NAME = "state_group_state_deduplication"
STATE_GROUP_INDEX_UPDATE_NAME = "state_group_state_type_index"
@ -1305,7 +1296,7 @@ class StateStore(StateGroupWorkerStore, BackgroundUpdateStore):
EVENT_STATE_GROUP_INDEX_UPDATE_NAME = "event_to_state_groups_sg_index"
def __init__(self, db_conn, hs):
super(StateStore, self).__init__(db_conn, hs)
super(StateBackgroundUpdateStore, self).__init__(db_conn, hs)
self.register_background_update_handler(
self.STATE_GROUP_DEDUPLICATION_UPDATE_NAME,
self._background_deduplicate_state,
@ -1327,34 +1318,6 @@ class StateStore(StateGroupWorkerStore, BackgroundUpdateStore):
columns=["state_group"],
)
def _store_event_state_mappings_txn(self, txn, events_and_contexts):
state_groups = {}
for event, context in events_and_contexts:
if event.internal_metadata.is_outlier():
continue
# if the event was rejected, just give it the same state as its
# predecessor.
if context.rejected:
state_groups[event.event_id] = context.prev_group
continue
state_groups[event.event_id] = context.state_group
self._simple_insert_many_txn(
txn,
table="event_to_state_groups",
values=[
{"state_group": state_group_id, "event_id": event_id}
for event_id, state_group_id in iteritems(state_groups)
],
)
for event_id, state_group_id in iteritems(state_groups):
txn.call_after(
self._get_state_group_for_event.prefill, (event_id,), state_group_id
)
@defer.inlineCallbacks
def _background_deduplicate_state(self, progress, batch_size):
"""This background update will slowly deduplicate state by reencoding
@ -1527,3 +1490,54 @@ class StateStore(StateGroupWorkerStore, BackgroundUpdateStore):
yield self._end_background_update(self.STATE_GROUP_INDEX_UPDATE_NAME)
return 1
class StateStore(StateGroupWorkerStore, StateBackgroundUpdateStore):
""" Keeps track of the state at a given event.
This is done by the concept of `state groups`. Every event is a assigned
a state group (identified by an arbitrary string), which references a
collection of state events. The current state of an event is then the
collection of state events referenced by the event's state group.
Hence, every change in the current state causes a new state group to be
generated. However, if no change happens (e.g., if we get a message event
with only one parent it inherits the state group from its parent.)
There are three tables:
* `state_groups`: Stores group name, first event with in the group and
room id.
* `event_to_state_groups`: Maps events to state groups.
* `state_groups_state`: Maps state group to state events.
"""
def __init__(self, db_conn, hs):
super(StateStore, self).__init__(db_conn, hs)
def _store_event_state_mappings_txn(self, txn, events_and_contexts):
state_groups = {}
for event, context in events_and_contexts:
if event.internal_metadata.is_outlier():
continue
# if the event was rejected, just give it the same state as its
# predecessor.
if context.rejected:
state_groups[event.event_id] = context.prev_group
continue
state_groups[event.event_id] = context.state_group
self._simple_insert_many_txn(
txn,
table="event_to_state_groups",
values=[
{"state_group": state_group_id, "event_id": event_id}
for event_id, state_group_id in iteritems(state_groups)
],
)
for event_id, state_group_id in iteritems(state_groups):
txn.call_after(
self._get_state_group_for_event.prefill, (event_id,), state_group_id
)