Merge pull request #1620 from matrix-org/erikj/concurrent_room_access
Limit the number of events that can be created on a given room concurrently
This commit is contained in:
Erik Johnston
GitHub
commit
d53a80af25
|
|
@ -24,7 +24,7 @@ from synapse.push.action_generator import ActionGenerator
|
|||
from synapse.types import (
|
||||
UserID, RoomAlias, RoomStreamToken,
|
||||
)
|
||||
from synapse.util.async import run_on_reactor, ReadWriteLock
|
||||
from synapse.util.async import run_on_reactor, ReadWriteLock, Limiter
|
||||
from synapse.util.logcontext import preserve_fn
|
||||
from synapse.util.metrics import measure_func
|
||||
from synapse.visibility import filter_events_for_client
|
||||
|
|
@ -50,6 +50,10 @@ class MessageHandler(BaseHandler):
|
|||
|
||||
self.pagination_lock = ReadWriteLock()
|
||||
|
||||
# We arbitrarily limit concurrent event creation for a room to 5.
|
||||
# This is to stop us from diverging history *too* much.
|
||||
self.limiter = Limiter(max_count=5)
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def purge_history(self, room_id, event_id):
|
||||
event = yield self.store.get_event(event_id)
|
||||
|
|
@ -191,36 +195,38 @@ class MessageHandler(BaseHandler):
|
|||
"""
|
||||
builder = self.event_builder_factory.new(event_dict)
|
||||
|
||||
self.validator.validate_new(builder)
|
||||
with (yield self.limiter.queue(builder.room_id)):
|
||||
self.validator.validate_new(builder)
|
||||
|
||||
if builder.type == EventTypes.Member:
|
||||
membership = builder.content.get("membership", None)
|
||||
target = UserID.from_string(builder.state_key)
|
||||
if builder.type == EventTypes.Member:
|
||||
membership = builder.content.get("membership", None)
|
||||
target = UserID.from_string(builder.state_key)
|
||||
|
||||
if membership in {Membership.JOIN, Membership.INVITE}:
|
||||
# If event doesn't include a display name, add one.
|
||||
profile = self.hs.get_handlers().profile_handler
|
||||
content = builder.content
|
||||
if membership in {Membership.JOIN, Membership.INVITE}:
|
||||
# If event doesn't include a display name, add one.
|
||||
profile = self.hs.get_handlers().profile_handler
|
||||
content = builder.content
|
||||
|
||||
try:
|
||||
content["displayname"] = yield profile.get_displayname(target)
|
||||
content["avatar_url"] = yield profile.get_avatar_url(target)
|
||||
except Exception as e:
|
||||
logger.info(
|
||||
"Failed to get profile information for %r: %s",
|
||||
target, e
|
||||
)
|
||||
try:
|
||||
content["displayname"] = yield profile.get_displayname(target)
|
||||
content["avatar_url"] = yield profile.get_avatar_url(target)
|
||||
except Exception as e:
|
||||
logger.info(
|
||||
"Failed to get profile information for %r: %s",
|
||||
target, e
|
||||
)
|
||||
|
||||
if token_id is not None:
|
||||
builder.internal_metadata.token_id = token_id
|
||||
if token_id is not None:
|
||||
builder.internal_metadata.token_id = token_id
|
||||
|
||||
if txn_id is not None:
|
||||
builder.internal_metadata.txn_id = txn_id
|
||||
if txn_id is not None:
|
||||
builder.internal_metadata.txn_id = txn_id
|
||||
|
||||
event, context = yield self._create_new_client_event(
|
||||
builder=builder,
|
||||
prev_event_ids=prev_event_ids,
|
||||
)
|
||||
|
||||
event, context = yield self._create_new_client_event(
|
||||
builder=builder,
|
||||
prev_event_ids=prev_event_ids,
|
||||
)
|
||||
defer.returnValue((event, context))
|
||||
|
||||
@defer.inlineCallbacks
|
||||
|
|
|
|||
|
|
@ -197,6 +197,64 @@ class Linearizer(object):
|
|||
defer.returnValue(_ctx_manager())
|
||||
|
||||
|
||||
class Limiter(object):
|
||||
"""Limits concurrent access to resources based on a key. Useful to ensure
|
||||
only a few thing happen at a time on a given resource.
|
||||
|
||||
Example:
|
||||
|
||||
with (yield limiter.queue("test_key")):
|
||||
# do some work.
|
||||
|
||||
"""
|
||||
def __init__(self, max_count):
|
||||
"""
|
||||
Args:
|
||||
max_count(int): The maximum number of concurrent access
|
||||
"""
|
||||
self.max_count = max_count
|
||||
|
||||
# key_to_defer is a map from the key to a 2 element list where
|
||||
# the first element is the number of things executing
|
||||
# the second element is a list of deferreds for the things blocked from
|
||||
# executing.
|
||||
self.key_to_defer = {}
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def queue(self, key):
|
||||
entry = self.key_to_defer.setdefault(key, [0, []])
|
||||
|
||||
# If the number of things executing is greater than the maximum
|
||||
# then add a deferred to the list of blocked items
|
||||
# When on of the things currently executing finishes it will callback
|
||||
# this item so that it can continue executing.
|
||||
if entry[0] >= self.max_count:
|
||||
new_defer = defer.Deferred()
|
||||
entry[1].append(new_defer)
|
||||
with PreserveLoggingContext():
|
||||
yield new_defer
|
||||
|
||||
entry[0] += 1
|
||||
|
||||
@contextmanager
|
||||
def _ctx_manager():
|
||||
try:
|
||||
yield
|
||||
finally:
|
||||
# We've finished executing so check if there are any things
|
||||
# blocked waiting to execute and start one of them
|
||||
entry[0] -= 1
|
||||
try:
|
||||
entry[1].pop(0).callback(None)
|
||||
except IndexError:
|
||||
# If nothing else is executing for this key then remove it
|
||||
# from the map
|
||||
if entry[0] == 0:
|
||||
self.key_to_defer.pop(key, None)
|
||||
|
||||
defer.returnValue(_ctx_manager())
|
||||
|
||||
|
||||
class ReadWriteLock(object):
|
||||
"""A deferred style read write lock.
|
||||
|
||||
|
|
|
|||
70
tests/util/test_limiter.py
Normal file
70
tests/util/test_limiter.py
Normal file
|
|
@ -0,0 +1,70 @@
|
|||
# -*- coding: utf-8 -*-
|
||||
# Copyright 2016 OpenMarket Ltd
|
||||
#
|
||||
# Licensed under the Apache License, Version 2.0 (the "License");
|
||||
# you may not use this file except in compliance with the License.
|
||||
# You may obtain a copy of the License at
|
||||
#
|
||||
# http://www.apache.org/licenses/LICENSE-2.0
|
||||
#
|
||||
# Unless required by applicable law or agreed to in writing, software
|
||||
# distributed under the License is distributed on an "AS IS" BASIS,
|
||||
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
# See the License for the specific language governing permissions and
|
||||
# limitations under the License.
|
||||
|
||||
|
||||
from tests import unittest
|
||||
|
||||
from twisted.internet import defer
|
||||
|
||||
from synapse.util.async import Limiter
|
||||
|
||||
|
||||
class LimiterTestCase(unittest.TestCase):
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def test_limiter(self):
|
||||
limiter = Limiter(3)
|
||||
|
||||
key = object()
|
||||
|
||||
d1 = limiter.queue(key)
|
||||
cm1 = yield d1
|
||||
|
||||
d2 = limiter.queue(key)
|
||||
cm2 = yield d2
|
||||
|
||||
d3 = limiter.queue(key)
|
||||
cm3 = yield d3
|
||||
|
||||
d4 = limiter.queue(key)
|
||||
self.assertFalse(d4.called)
|
||||
|
||||
d5 = limiter.queue(key)
|
||||
self.assertFalse(d5.called)
|
||||
|
||||
with cm1:
|
||||
self.assertFalse(d4.called)
|
||||
self.assertFalse(d5.called)
|
||||
|
||||
self.assertTrue(d4.called)
|
||||
self.assertFalse(d5.called)
|
||||
|
||||
with cm3:
|
||||
self.assertFalse(d5.called)
|
||||
|
||||
self.assertTrue(d5.called)
|
||||
|
||||
with cm2:
|
||||
pass
|
||||
|
||||
with (yield d4):
|
||||
pass
|
||||
|
||||
with (yield d5):
|
||||
pass
|
||||
|
||||
d6 = limiter.queue(key)
|
||||
with (yield d6):
|
||||
pass
|
||||
Loading…
Reference in a new issue