Merge pull request #3586 from matrix-org/rav/optimise_resolve_state_groups

Fixes and optimisations for resolve_state_groups
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Richard van der Hoff 2018-07-24 14:11:45 +01:00 committed by GitHub
commit a321f78991
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4 changed files with 98 additions and 62 deletions

1
changelog.d/3586.misc Normal file
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@ -0,0 +1 @@
Fixes and optimisations for resolve_state_groups

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@ -249,7 +249,7 @@ class EventContext(object):
@defer.inlineCallbacks
def update_state(self, state_group, prev_state_ids, current_state_ids,
delta_ids):
prev_group, delta_ids):
"""Replace the state in the context
"""
@ -260,6 +260,7 @@ class EventContext(object):
self.state_group = state_group
self._prev_state_ids = prev_state_ids
self.prev_group = prev_group
self._current_state_ids = current_state_ids
self.delta_ids = delta_ids

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@ -1980,10 +1980,6 @@ class FederationHandler(BaseHandler):
current_state_ids.update(state_updates)
if context.delta_ids is not None:
delta_ids = dict(context.delta_ids)
delta_ids.update(state_updates)
prev_state_ids = yield context.get_prev_state_ids(self.store)
prev_state_ids = dict(prev_state_ids)
@ -1991,11 +1987,13 @@ class FederationHandler(BaseHandler):
k: a.event_id for k, a in iteritems(auth_events)
})
# create a new state group as a delta from the existing one.
prev_group = context.state_group
state_group = yield self.store.store_state_group(
event.event_id,
event.room_id,
prev_group=context.prev_group,
delta_ids=delta_ids,
prev_group=prev_group,
delta_ids=state_updates,
current_state_ids=current_state_ids,
)
@ -2003,7 +2001,8 @@ class FederationHandler(BaseHandler):
state_group=state_group,
current_state_ids=current_state_ids,
prev_state_ids=prev_state_ids,
delta_ids=delta_ids,
prev_group=prev_group,
delta_ids=state_updates,
)
@defer.inlineCallbacks

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@ -471,69 +471,39 @@ class StateResolutionHandler(object):
"Resolving state for %s with %d groups", room_id, len(state_groups_ids)
)
# build a map from state key to the event_ids which set that state.
# dict[(str, str), set[str])
state = {}
# start by assuming we won't have any conflicted state, and build up the new
# state map by iterating through the state groups. If we discover a conflict,
# we give up and instead use `resolve_events_with_factory`.
#
# XXX: is this actually worthwhile, or should we just let
# resolve_events_with_factory do it?
new_state = {}
conflicted_state = False
for st in itervalues(state_groups_ids):
for key, e_id in iteritems(st):
state.setdefault(key, set()).add(e_id)
# build a map from state key to the event_ids which set that state,
# including only those where there are state keys in conflict.
conflicted_state = {
k: list(v)
for k, v in iteritems(state)
if len(v) > 1
}
if key in new_state:
conflicted_state = True
break
new_state[key] = e_id
if conflicted_state:
break
if conflicted_state:
logger.info("Resolving conflicted state for %r", room_id)
with Measure(self.clock, "state._resolve_events"):
new_state = yield resolve_events_with_factory(
list(state_groups_ids.values()),
list(itervalues(state_groups_ids)),
event_map=event_map,
state_map_factory=state_map_factory,
)
else:
new_state = {
key: e_ids.pop() for key, e_ids in iteritems(state)
}
with Measure(self.clock, "state.create_group_ids"):
# if the new state matches any of the input state groups, we can
# use that state group again. Otherwise we will generate a state_id
# which will be used as a cache key for future resolutions, but
# not get persisted.
state_group = None
new_state_event_ids = frozenset(itervalues(new_state))
for sg, events in iteritems(state_groups_ids):
if new_state_event_ids == frozenset(e_id for e_id in events):
state_group = sg
break
# TODO: We want to create a state group for this set of events, to
# increase cache hits, but we need to make sure that it doesn't
# end up as a prev_group without being added to the database
prev_group = None
delta_ids = None
for old_group, old_ids in iteritems(state_groups_ids):
if not set(new_state) - set(old_ids):
n_delta_ids = {
k: v
for k, v in iteritems(new_state)
if old_ids.get(k) != v
}
if not delta_ids or len(n_delta_ids) < len(delta_ids):
prev_group = old_group
delta_ids = n_delta_ids
cache = _StateCacheEntry(
state=new_state,
state_group=state_group,
prev_group=prev_group,
delta_ids=delta_ids,
)
with Measure(self.clock, "state.create_group_ids"):
cache = _make_state_cache_entry(new_state, state_groups_ids)
if self._state_cache is not None:
self._state_cache[group_names] = cache
@ -541,6 +511,70 @@ class StateResolutionHandler(object):
defer.returnValue(cache)
def _make_state_cache_entry(
new_state,
state_groups_ids,
):
"""Given a resolved state, and a set of input state groups, pick one to base
a new state group on (if any), and return an appropriately-constructed
_StateCacheEntry.
Args:
new_state (dict[(str, str), str]): resolved state map (mapping from
(type, state_key) to event_id)
state_groups_ids (dict[int, dict[(str, str), str]]):
map from state group id to the state in that state group
(where 'state' is a map from state key to event id)
Returns:
_StateCacheEntry
"""
# if the new state matches any of the input state groups, we can
# use that state group again. Otherwise we will generate a state_id
# which will be used as a cache key for future resolutions, but
# not get persisted.
# first look for exact matches
new_state_event_ids = set(itervalues(new_state))
for sg, state in iteritems(state_groups_ids):
if len(new_state_event_ids) != len(state):
continue
old_state_event_ids = set(itervalues(state))
if new_state_event_ids == old_state_event_ids:
# got an exact match.
return _StateCacheEntry(
state=new_state,
state_group=sg,
)
# TODO: We want to create a state group for this set of events, to
# increase cache hits, but we need to make sure that it doesn't
# end up as a prev_group without being added to the database
# failing that, look for the closest match.
prev_group = None
delta_ids = None
for old_group, old_state in iteritems(state_groups_ids):
n_delta_ids = {
k: v
for k, v in iteritems(new_state)
if old_state.get(k) != v
}
if not delta_ids or len(n_delta_ids) < len(delta_ids):
prev_group = old_group
delta_ids = n_delta_ids
return _StateCacheEntry(
state=new_state,
state_group=None,
prev_group=prev_group,
delta_ids=delta_ids,
)
def _ordered_events(events):
def key_func(e):
return -int(e.depth), hashlib.sha1(e.event_id.encode()).hexdigest()
@ -582,7 +616,7 @@ def _seperate(state_sets):
with them in different state sets.
Args:
state_sets(list[dict[(str, str), str]]):
state_sets(iterable[dict[(str, str), str]]):
List of dicts of (type, state_key) -> event_id, which are the
different state groups to resolve.
@ -596,10 +630,11 @@ def _seperate(state_sets):
conflicted_state is a dict mapping (type, state_key) to a set of
event ids for conflicted state keys.
"""
unconflicted_state = dict(state_sets[0])
state_set_iterator = iter(state_sets)
unconflicted_state = dict(next(state_set_iterator))
conflicted_state = {}
for state_set in state_sets[1:]:
for state_set in state_set_iterator:
for key, value in iteritems(state_set):
# Check if there is an unconflicted entry for the state key.
unconflicted_value = unconflicted_state.get(key)