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-rw-r--r--synapse/app/_base.py99
-rw-r--r--synapse/app/appservice.py50
-rw-r--r--synapse/app/client_reader.py53
-rw-r--r--synapse/app/federation_reader.py53
-rw-r--r--synapse/app/federation_sender.py57
-rw-r--r--synapse/app/frontend_proxy.py64
-rwxr-xr-xsynapse/app/homeserver.py114
-rw-r--r--synapse/app/media_repository.py53
-rw-r--r--synapse/app/pusher.py57
-rw-r--r--synapse/app/synchrotron.py69
-rw-r--r--synapse/app/user_dir.py53
-rw-r--r--synapse/config/server.py23
-rw-r--r--synapse/config/workers.py1
-rw-r--r--synapse/crypto/keyring.py64
-rw-r--r--synapse/handlers/device.py68
-rw-r--r--synapse/handlers/federation.py2
-rw-r--r--synapse/handlers/sync.py126
-rw-r--r--synapse/push/bulk_push_rule_evaluator.py56
-rw-r--r--synapse/push/httppusher.py20
-rw-r--r--synapse/python_dependencies.py3
-rw-r--r--synapse/rest/client/v1/admin.py16
-rw-r--r--synapse/rest/client/v2_alpha/keys.py6
-rw-r--r--synapse/rest/client/v2_alpha/sync.py5
-rw-r--r--synapse/visibility.py14
24 files changed, 580 insertions, 546 deletions
diff --git a/synapse/app/_base.py b/synapse/app/_base.py
new file mode 100644
index 0000000000..cd0e815919
--- /dev/null
+++ b/synapse/app/_base.py
@@ -0,0 +1,99 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector 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.
+import gc
+import logging
+
+import affinity
+from daemonize import Daemonize
+from synapse.util import PreserveLoggingContext
+from synapse.util.rlimit import change_resource_limit
+from twisted.internet import reactor
+
+
+def start_worker_reactor(appname, config):
+    """ Run the reactor in the main process
+
+    Daemonizes if necessary, and then configures some resources, before starting
+    the reactor. Pulls configuration from the 'worker' settings in 'config'.
+
+    Args:
+        appname (str): application name which will be sent to syslog
+        config (synapse.config.Config): config object
+    """
+
+    logger = logging.getLogger(config.worker_app)
+
+    start_reactor(
+        appname,
+        config.soft_file_limit,
+        config.gc_thresholds,
+        config.worker_pid_file,
+        config.worker_daemonize,
+        config.worker_cpu_affinity,
+        logger,
+    )
+
+
+def start_reactor(
+        appname,
+        soft_file_limit,
+        gc_thresholds,
+        pid_file,
+        daemonize,
+        cpu_affinity,
+        logger,
+):
+    """ Run the reactor in the main process
+
+    Daemonizes if necessary, and then configures some resources, before starting
+    the reactor
+
+    Args:
+        appname (str): application name which will be sent to syslog
+        soft_file_limit (int):
+        gc_thresholds:
+        pid_file (str): name of pid file to write to if daemonize is True
+        daemonize (bool): true to run the reactor in a background process
+        cpu_affinity (int|None): cpu affinity mask
+        logger (logging.Logger): logger instance to pass to Daemonize
+    """
+
+    def run():
+        # make sure that we run the reactor with the sentinel log context,
+        # otherwise other PreserveLoggingContext instances will get confused
+        # and complain when they see the logcontext arbitrarily swapping
+        # between the sentinel and `run` logcontexts.
+        with PreserveLoggingContext():
+            logger.info("Running")
+            if cpu_affinity is not None:
+                logger.info("Setting CPU affinity to %s" % cpu_affinity)
+                affinity.set_process_affinity_mask(0, cpu_affinity)
+            change_resource_limit(soft_file_limit)
+            if gc_thresholds:
+                gc.set_threshold(*gc_thresholds)
+            reactor.run()
+
+    if daemonize:
+        daemon = Daemonize(
+            app=appname,
+            pid=pid_file,
+            action=run,
+            auto_close_fds=False,
+            verbose=True,
+            logger=logger,
+        )
+        daemon.start()
+    else:
+        run()
diff --git a/synapse/app/appservice.py b/synapse/app/appservice.py
index 9a476efa63..ba2657bbad 100644
--- a/synapse/app/appservice.py
+++ b/synapse/app/appservice.py
@@ -13,38 +13,31 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
-from synapse.server import HomeServer
+from synapse import events
+from synapse.app import _base
 from synapse.config._base import ConfigError
-from synapse.config.logger import setup_logging
 from synapse.config.homeserver import HomeServerConfig
+from synapse.config.logger import setup_logging
 from synapse.http.site import SynapseSite
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
+from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.slave.storage.events import SlavedEventStore
-from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.replication.tcp.client import ReplicationClientHandler
+from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, preserve_fn
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-
-from synapse import events
-
 from twisted.internet import reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.appservice")
 
 
@@ -181,36 +174,13 @@ def start(config_options):
     ps.setup()
     ps.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ps.get_datastore().start_profiling()
         ps.get_state_handler().start_caching()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-appservice",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-appservice", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/client_reader.py b/synapse/app/client_reader.py
index 09bc1935f1..129cfa901f 100644
--- a/synapse/app/client_reader.py
+++ b/synapse/app/client_reader.py
@@ -13,47 +13,39 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
+from synapse import events
+from synapse.app import _base
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
-from synapse.http.site import SynapseSite
+from synapse.crypto import context_factory
 from synapse.http.server import JsonResource
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.http.site import SynapseSite
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
 from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
+from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.keys import SlavedKeyStore
-from synapse.replication.slave.storage.room import RoomStore
-from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
+from synapse.replication.slave.storage.room import RoomStore
 from synapse.replication.slave.storage.transactions import TransactionStore
 from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.rest.client.v1.room import PublicRoomListRestServlet
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-from synapse.crypto import context_factory
-
-from synapse import events
-
-
 from twisted.internet import reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.client_reader")
 
 
@@ -183,36 +175,13 @@ def start(config_options):
     ss.get_handlers()
     ss.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ss.get_state_handler().start_caching()
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-client-reader",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-client-reader", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/federation_reader.py b/synapse/app/federation_reader.py
index eb392e1c9d..40cebe6f4a 100644
--- a/synapse/app/federation_reader.py
+++ b/synapse/app/federation_reader.py
@@ -13,44 +13,36 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
+from synapse import events
+from synapse.api.urls import FEDERATION_PREFIX
+from synapse.app import _base
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
+from synapse.crypto import context_factory
+from synapse.federation.transport.server import TransportLayerServer
 from synapse.http.site import SynapseSite
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
+from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.keys import SlavedKeyStore
 from synapse.replication.slave.storage.room import RoomStore
 from synapse.replication.slave.storage.transactions import TransactionStore
-from synapse.replication.slave.storage.directory import DirectoryStore
 from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-from synapse.api.urls import FEDERATION_PREFIX
-from synapse.federation.transport.server import TransportLayerServer
-from synapse.crypto import context_factory
-
-from synapse import events
-
-
 from twisted.internet import reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.federation_reader")
 
 
@@ -172,36 +164,13 @@ def start(config_options):
     ss.get_handlers()
     ss.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ss.get_state_handler().start_caching()
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-federation-reader",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-federation-reader", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/federation_sender.py b/synapse/app/federation_sender.py
index 03327dc47a..389e3909d1 100644
--- a/synapse/app/federation_sender.py
+++ b/synapse/app/federation_sender.py
@@ -13,44 +13,37 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
-from synapse.server import HomeServer
+from synapse import events
+from synapse.app import _base
 from synapse.config._base import ConfigError
-from synapse.config.logger import setup_logging
 from synapse.config.homeserver import HomeServerConfig
+from synapse.config.logger import setup_logging
 from synapse.crypto import context_factory
-from synapse.http.site import SynapseSite
 from synapse.federation import send_queue
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.http.site import SynapseSite
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage.deviceinbox import SlavedDeviceInboxStore
+from synapse.replication.slave.storage.devices import SlavedDeviceStore
 from synapse.replication.slave.storage.events import SlavedEventStore
+from synapse.replication.slave.storage.presence import SlavedPresenceStore
 from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
-from synapse.replication.slave.storage.presence import SlavedPresenceStore
 from synapse.replication.slave.storage.transactions import TransactionStore
-from synapse.replication.slave.storage.devices import SlavedDeviceStore
 from synapse.replication.tcp.client import ReplicationClientHandler
+from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.async import Linearizer
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, preserve_fn
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-
-from synapse import events
-
-from twisted.internet import reactor, defer
+from twisted.internet import defer, reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.federation_sender")
 
 
@@ -213,36 +206,12 @@ def start(config_options):
     ps.setup()
     ps.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ps.get_datastore().start_profiling()
         ps.get_state_handler().start_caching()
 
     reactor.callWhenRunning(start)
-
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-federation-sender",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-federation-sender", config)
 
 
 class FederationSenderHandler(object):
diff --git a/synapse/app/frontend_proxy.py b/synapse/app/frontend_proxy.py
index 132f18a979..bee4c47498 100644
--- a/synapse/app/frontend_proxy.py
+++ b/synapse/app/frontend_proxy.py
@@ -13,48 +13,39 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
+from synapse import events
+from synapse.api.errors import SynapseError
+from synapse.app import _base
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
-from synapse.http.site import SynapseSite
+from synapse.crypto import context_factory
 from synapse.http.server import JsonResource
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.http.servlet import (
+    RestServlet, parse_json_object_from_request,
+)
+from synapse.http.site import SynapseSite
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
+from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
 from synapse.replication.slave.storage.devices import SlavedDeviceStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
-from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.tcp.client import ReplicationClientHandler
+from synapse.rest.client.v2_alpha._base import client_v2_patterns
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-from synapse.crypto import context_factory
-from synapse.api.errors import SynapseError
-from synapse.http.servlet import (
-    RestServlet, parse_json_object_from_request,
-)
-from synapse.rest.client.v2_alpha._base import client_v2_patterns
-
-from synapse import events
-
-
-from twisted.internet import reactor, defer
+from twisted.internet import defer, reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
-
 logger = logging.getLogger("synapse.app.frontend_proxy")
 
 
@@ -234,36 +225,13 @@ def start(config_options):
     ss.get_handlers()
     ss.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ss.get_state_handler().start_caching()
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-frontend-proxy",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-frontend-proxy", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 081e7cce59..84ad8f04a0 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -13,61 +13,48 @@
 # 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.
-
-import synapse
-
 import gc
 import logging
 import os
 import sys
 
+import synapse
 import synapse.config.logger
+from synapse import events
+from synapse.api.urls import CONTENT_REPO_PREFIX, FEDERATION_PREFIX, \
+    LEGACY_MEDIA_PREFIX, MEDIA_PREFIX, SERVER_KEY_PREFIX, SERVER_KEY_V2_PREFIX, \
+    STATIC_PREFIX, WEB_CLIENT_PREFIX
+from synapse.app import _base
 from synapse.config._base import ConfigError
-
-from synapse.python_dependencies import (
-    check_requirements, CONDITIONAL_REQUIREMENTS
-)
-
-from synapse.rest import ClientRestResource
-from synapse.storage.engines import create_engine, IncorrectDatabaseSetup
-from synapse.storage import are_all_users_on_domain
-from synapse.storage.prepare_database import UpgradeDatabaseException, prepare_database
-
-from synapse.server import HomeServer
-
-from twisted.internet import reactor, defer
-from twisted.application import service
-from twisted.web.resource import Resource, EncodingResourceWrapper
-from twisted.web.static import File
-from twisted.web.server import GzipEncoderFactory
-from synapse.http.server import RootRedirect
-from synapse.rest.media.v0.content_repository import ContentRepoResource
-from synapse.rest.media.v1.media_repository import MediaRepositoryResource
-from synapse.rest.key.v1.server_key_resource import LocalKey
-from synapse.rest.key.v2 import KeyApiV2Resource
-from synapse.api.urls import (
-    FEDERATION_PREFIX, WEB_CLIENT_PREFIX, CONTENT_REPO_PREFIX,
-    SERVER_KEY_PREFIX, LEGACY_MEDIA_PREFIX, MEDIA_PREFIX, STATIC_PREFIX,
-    SERVER_KEY_V2_PREFIX,
-)
 from synapse.config.homeserver import HomeServerConfig
 from synapse.crypto import context_factory
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.federation.transport.server import TransportLayerServer
+from synapse.http.server import RootRedirect
+from synapse.http.site import SynapseSite
 from synapse.metrics import register_memory_metrics
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
+from synapse.python_dependencies import CONDITIONAL_REQUIREMENTS, \
+    check_requirements
 from synapse.replication.tcp.resource import ReplicationStreamProtocolFactory
-from synapse.federation.transport.server import TransportLayerServer
-
-from synapse.util.rlimit import change_resource_limit
-from synapse.util.versionstring import get_version_string
+from synapse.rest import ClientRestResource
+from synapse.rest.key.v1.server_key_resource import LocalKey
+from synapse.rest.key.v2 import KeyApiV2Resource
+from synapse.rest.media.v0.content_repository import ContentRepoResource
+from synapse.rest.media.v1.media_repository import MediaRepositoryResource
+from synapse.server import HomeServer
+from synapse.storage import are_all_users_on_domain
+from synapse.storage.engines import IncorrectDatabaseSetup, create_engine
+from synapse.storage.prepare_database import UpgradeDatabaseException, prepare_database
 from synapse.util.httpresourcetree import create_resource_tree
+from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
-
-from synapse.http.site import SynapseSite
-
-from synapse import events
-
-from daemonize import Daemonize
+from synapse.util.rlimit import change_resource_limit
+from synapse.util.versionstring import get_version_string
+from twisted.application import service
+from twisted.internet import defer, reactor
+from twisted.web.resource import EncodingResourceWrapper, Resource
+from twisted.web.server import GzipEncoderFactory
+from twisted.web.static import File
 
 logger = logging.getLogger("synapse.app.homeserver")
 
@@ -446,37 +433,18 @@ def run(hs):
         # be quite busy the first few minutes
         clock.call_later(5 * 60, phone_stats_home)
 
-    def in_thread():
-        # Uncomment to enable tracing of log context changes.
-        # sys.settrace(logcontext_tracer)
-
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            change_resource_limit(hs.config.soft_file_limit)
-            if hs.config.gc_thresholds:
-                gc.set_threshold(*hs.config.gc_thresholds)
-            reactor.run()
-
-    if hs.config.daemonize:
-
-        if hs.config.print_pidfile:
-            print (hs.config.pid_file)
-
-        daemon = Daemonize(
-            app="synapse-homeserver",
-            pid=hs.config.pid_file,
-            action=lambda: in_thread(),
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-
-        daemon.start()
-    else:
-        in_thread()
+    if hs.config.daemonize and hs.config.print_pidfile:
+        print (hs.config.pid_file)
+
+    _base.start_reactor(
+        "synapse-homeserver",
+        hs.config.soft_file_limit,
+        hs.config.gc_thresholds,
+        hs.config.pid_file,
+        hs.config.daemonize,
+        hs.config.cpu_affinity,
+        logger,
+    )
 
 
 def main():
diff --git a/synapse/app/media_repository.py b/synapse/app/media_repository.py
index f57ec784fe..36c18bdbcb 100644
--- a/synapse/app/media_repository.py
+++ b/synapse/app/media_repository.py
@@ -13,14 +13,21 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
+from synapse import events
+from synapse.api.urls import (
+    CONTENT_REPO_PREFIX, LEGACY_MEDIA_PREFIX, MEDIA_PREFIX
+)
+from synapse.app import _base
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
+from synapse.crypto import context_factory
 from synapse.http.site import SynapseSite
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
 from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
@@ -33,27 +40,12 @@ from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.media_repository import MediaRepositoryStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
+from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-from synapse.api.urls import (
-    CONTENT_REPO_PREFIX, LEGACY_MEDIA_PREFIX, MEDIA_PREFIX
-)
-from synapse.crypto import context_factory
-
-from synapse import events
-
-
 from twisted.internet import reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.media_repository")
 
 
@@ -180,36 +172,13 @@ def start(config_options):
     ss.get_handlers()
     ss.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ss.get_state_handler().start_caching()
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-media-repository",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-media-repository", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/pusher.py b/synapse/app/pusher.py
index f9114acfcb..db9a4d16f4 100644
--- a/synapse/app/pusher.py
+++ b/synapse/app/pusher.py
@@ -13,41 +13,33 @@
 # 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.
+import logging
+import sys
 
 import synapse
-
-from synapse.server import HomeServer
+from synapse import events
+from synapse.app import _base
 from synapse.config._base import ConfigError
-from synapse.config.logger import setup_logging
 from synapse.config.homeserver import HomeServerConfig
+from synapse.config.logger import setup_logging
 from synapse.http.site import SynapseSite
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
-from synapse.storage.roommember import RoomMemberStore
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
+from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
 from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.pushers import SlavedPusherStore
 from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
-from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
 from synapse.replication.tcp.client import ReplicationClientHandler
-from synapse.storage.engines import create_engine
+from synapse.server import HomeServer
 from synapse.storage import DataStore
+from synapse.storage.engines import create_engine
+from synapse.storage.roommember import RoomMemberStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn, \
-    PreserveLoggingContext
+from synapse.util.logcontext import LoggingContext, preserve_fn
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-
-from synapse import events
-
-from twisted.internet import reactor, defer
+from twisted.internet import defer, reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.pusher")
 
 
@@ -244,18 +236,6 @@ def start(config_options):
     ps.setup()
     ps.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ps.get_pusherpool().start()
         ps.get_datastore().start_profiling()
@@ -263,18 +243,7 @@ def start(config_options):
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-pusher",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-pusher", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/synchrotron.py b/synapse/app/synchrotron.py
index d06a05acd9..576ac6fb7e 100644
--- a/synapse/app/synchrotron.py
+++ b/synapse/app/synchrotron.py
@@ -13,57 +13,51 @@
 # 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.
+import contextlib
+import logging
+import sys
 
 import synapse
-
 from synapse.api.constants import EventTypes
+from synapse.app import _base
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.config.logger import setup_logging
 from synapse.handlers.presence import PresenceHandler, get_interested_parties
-from synapse.http.site import SynapseSite
 from synapse.http.server import JsonResource
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
-from synapse.rest.client.v2_alpha import sync
-from synapse.rest.client.v1 import events
-from synapse.rest.client.v1.room import RoomInitialSyncRestServlet
-from synapse.rest.client.v1.initial_sync import InitialSyncRestServlet
+from synapse.http.site import SynapseSite
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
-from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
-from synapse.replication.slave.storage.events import SlavedEventStore
-from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
 from synapse.replication.slave.storage.account_data import SlavedAccountDataStore
 from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
-from synapse.replication.slave.storage.registration import SlavedRegistrationStore
-from synapse.replication.slave.storage.filtering import SlavedFilteringStore
-from synapse.replication.slave.storage.push_rule import SlavedPushRuleStore
-from synapse.replication.slave.storage.presence import SlavedPresenceStore
+from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
 from synapse.replication.slave.storage.deviceinbox import SlavedDeviceInboxStore
 from synapse.replication.slave.storage.devices import SlavedDeviceStore
+from synapse.replication.slave.storage.events import SlavedEventStore
+from synapse.replication.slave.storage.filtering import SlavedFilteringStore
+from synapse.replication.slave.storage.presence import SlavedPresenceStore
+from synapse.replication.slave.storage.push_rule import SlavedPushRuleStore
+from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
+from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.replication.slave.storage.room import RoomStore
 from synapse.replication.slave.storage.groups import SlavedGroupServerStore
 from synapse.replication.tcp.client import ReplicationClientHandler
+from synapse.rest.client.v1 import events
+from synapse.rest.client.v1.initial_sync import InitialSyncRestServlet
+from synapse.rest.client.v1.room import RoomInitialSyncRestServlet
+from synapse.rest.client.v2_alpha import sync
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.presence import UserPresenceState
 from synapse.storage.roommember import RoomMemberStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, preserve_fn
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.stringutils import random_string
 from synapse.util.versionstring import get_version_string
-
-from twisted.internet import reactor, defer
+from twisted.internet import defer, reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import contextlib
-import gc
-
 logger = logging.getLogger("synapse.app.synchrotron")
 
 
@@ -446,36 +440,13 @@ def start(config_options):
     ss.setup()
     ss.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ss.get_datastore().start_profiling()
         ss.get_state_handler().start_caching()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-synchrotron",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-synchrotron", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/app/user_dir.py b/synapse/app/user_dir.py
index 8c6300db9d..be661a70c7 100644
--- a/synapse/app/user_dir.py
+++ b/synapse/app/user_dir.py
@@ -14,16 +14,19 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import synapse
+import logging
+import sys
 
-from synapse.server import HomeServer
+import synapse
+from synapse import events
+from synapse.app import _base
 from synapse.config._base import ConfigError
-from synapse.config.logger import setup_logging
 from synapse.config.homeserver import HomeServerConfig
+from synapse.config.logger import setup_logging
 from synapse.crypto import context_factory
-from synapse.http.site import SynapseSite
 from synapse.http.server import JsonResource
-from synapse.metrics.resource import MetricsResource, METRICS_PREFIX
+from synapse.http.site import SynapseSite
+from synapse.metrics.resource import METRICS_PREFIX, MetricsResource
 from synapse.replication.slave.storage._base import BaseSlavedStore
 from synapse.replication.slave.storage.appservice import SlavedApplicationServiceStore
 from synapse.replication.slave.storage.client_ips import SlavedClientIpStore
@@ -31,26 +34,17 @@ from synapse.replication.slave.storage.events import SlavedEventStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.rest.client.v2_alpha import user_directory
+from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.user_directory import UserDirectoryStore
+from synapse.util.caches.stream_change_cache import StreamChangeCache
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, preserve_fn
 from synapse.util.manhole import manhole
-from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
-from synapse.util.caches.stream_change_cache import StreamChangeCache
-
-from synapse import events
-
 from twisted.internet import reactor
 from twisted.web.resource import Resource
 
-from daemonize import Daemonize
-
-import sys
-import logging
-import gc
-
 logger = logging.getLogger("synapse.app.user_dir")
 
 
@@ -233,36 +227,13 @@ def start(config_options):
     ps.setup()
     ps.start_listening(config.worker_listeners)
 
-    def run():
-        # make sure that we run the reactor with the sentinel log context,
-        # otherwise other PreserveLoggingContext instances will get confused
-        # and complain when they see the logcontext arbitrarily swapping
-        # between the sentinel and `run` logcontexts.
-        with PreserveLoggingContext():
-            logger.info("Running")
-            change_resource_limit(config.soft_file_limit)
-            if config.gc_thresholds:
-                gc.set_threshold(*config.gc_thresholds)
-            reactor.run()
-
     def start():
         ps.get_datastore().start_profiling()
         ps.get_state_handler().start_caching()
 
     reactor.callWhenRunning(start)
 
-    if config.worker_daemonize:
-        daemon = Daemonize(
-            app="synapse-user-dir",
-            pid=config.worker_pid_file,
-            action=run,
-            auto_close_fds=False,
-            verbose=True,
-            logger=logger,
-        )
-        daemon.start()
-    else:
-        run()
+    _base.start_worker_reactor("synapse-user-dir", config)
 
 
 if __name__ == '__main__':
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 28b4e5f50c..89d61a0503 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -29,6 +30,7 @@ class ServerConfig(Config):
         self.user_agent_suffix = config.get("user_agent_suffix")
         self.use_frozen_dicts = config.get("use_frozen_dicts", False)
         self.public_baseurl = config.get("public_baseurl")
+        self.cpu_affinity = config.get("cpu_affinity")
 
         # Whether to send federation traffic out in this process. This only
         # applies to some federation traffic, and so shouldn't be used to
@@ -147,6 +149,27 @@ class ServerConfig(Config):
         # When running as a daemon, the file to store the pid in
         pid_file: %(pid_file)s
 
+        # CPU affinity mask. Setting this restricts the CPUs on which the
+        # process will be scheduled. It is represented as a bitmask, with the
+        # lowest order bit corresponding to the first logical CPU and the
+        # highest order bit corresponding to the last logical CPU. Not all CPUs
+        # may exist on a given system but a mask may specify more CPUs than are
+        # present.
+        #
+        # For example:
+        #    0x00000001  is processor #0,
+        #    0x00000003  is processors #0 and #1,
+        #    0xFFFFFFFF  is all processors (#0 through #31).
+        #
+        # Pinning a Python process to a single CPU is desirable, because Python
+        # is inherently single-threaded due to the GIL, and can suffer a
+        # 30-40%% slowdown due to cache blow-out and thread context switching
+        # if the scheduler happens to schedule the underlying threads across
+        # different cores. See
+        # https://www.mirantis.com/blog/improve-performance-python-programs-restricting-single-cpu/.
+        #
+        # cpu_affinity: 0xFFFFFFFF
+
         # Whether to serve a web client from the HTTP/HTTPS root resource.
         web_client: True
 
diff --git a/synapse/config/workers.py b/synapse/config/workers.py
index 99d5d8aaeb..c5a5a8919c 100644
--- a/synapse/config/workers.py
+++ b/synapse/config/workers.py
@@ -33,6 +33,7 @@ class WorkerConfig(Config):
         self.worker_name = config.get("worker_name", self.worker_app)
 
         self.worker_main_http_uri = config.get("worker_main_http_uri", None)
+        self.worker_cpu_affinity = config.get("worker_cpu_affinity")
 
         if self.worker_listeners:
             for listener in self.worker_listeners:
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index 1bb27edc0f..51851d04e5 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -15,10 +16,9 @@
 
 from synapse.crypto.keyclient import fetch_server_key
 from synapse.api.errors import SynapseError, Codes
-from synapse.util import unwrapFirstError
-from synapse.util.async import ObservableDeferred
+from synapse.util import unwrapFirstError, logcontext
 from synapse.util.logcontext import (
-    preserve_context_over_deferred, preserve_context_over_fn, PreserveLoggingContext,
+    preserve_context_over_fn, PreserveLoggingContext,
     preserve_fn
 )
 from synapse.util.metrics import Measure
@@ -74,6 +74,11 @@ class Keyring(object):
         self.perspective_servers = self.config.perspectives
         self.hs = hs
 
+        # map from server name to Deferred. Has an entry for each server with
+        # an ongoing key download; the Deferred completes once the download
+        # completes.
+        #
+        # These are regular, logcontext-agnostic Deferreds.
         self.key_downloads = {}
 
     def verify_json_for_server(self, server_name, json_object):
@@ -82,7 +87,7 @@ class Keyring(object):
         )[0]
 
     def verify_json_objects_for_server(self, server_and_json):
-        """Bulk verfies signatures of json objects, bulk fetching keys as
+        """Bulk verifies signatures of json objects, bulk fetching keys as
         necessary.
 
         Args:
@@ -212,7 +217,13 @@ class Keyring(object):
         Args:
             server_names (list): list of server_names we want to lookup
             server_to_deferred (dict): server_name to deferred which gets
-                resolved once we've finished looking up keys for that server
+                resolved once we've finished looking up keys for that server.
+                The Deferreds should be regular twisted ones which call their
+                callbacks with no logcontext.
+
+        Returns: a Deferred which resolves once all key lookups for the given
+            servers have completed. Follows the synapse rules of logcontext
+            preservation.
         """
         while True:
             wait_on = [
@@ -226,15 +237,13 @@ class Keyring(object):
             else:
                 break
 
-        for server_name, deferred in server_to_deferred.items():
-            d = ObservableDeferred(preserve_context_over_deferred(deferred))
-            self.key_downloads[server_name] = d
-
-            def rm(r, server_name):
-                self.key_downloads.pop(server_name, None)
-                return r
+        def rm(r, server_name_):
+            self.key_downloads.pop(server_name_, None)
+            return r
 
-            d.addBoth(rm, server_name)
+        for server_name, deferred in server_to_deferred.items():
+            self.key_downloads[server_name] = deferred
+            deferred.addBoth(rm, server_name)
 
     def get_server_verify_keys(self, verify_requests):
         """Tries to find at least one key for each verify request
@@ -333,7 +342,7 @@ class Keyring(object):
             Deferred: resolves to dict[str, dict[str, VerifyKey]]: map from
                 server_name -> key_id -> VerifyKey
         """
-        res = yield preserve_context_over_deferred(defer.gatherResults(
+        res = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self.store.get_server_verify_keys)(
                     server_name, key_ids
@@ -341,7 +350,7 @@ class Keyring(object):
                 for server_name, key_ids in server_name_and_key_ids
             ],
             consumeErrors=True,
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         defer.returnValue(dict(res))
 
@@ -362,13 +371,13 @@ class Keyring(object):
                 )
                 defer.returnValue({})
 
-        results = yield preserve_context_over_deferred(defer.gatherResults(
+        results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(get_key)(p_name, p_keys)
                 for p_name, p_keys in self.perspective_servers.items()
             ],
             consumeErrors=True,
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         union_of_keys = {}
         for result in results:
@@ -402,13 +411,13 @@ class Keyring(object):
 
             defer.returnValue(keys)
 
-        results = yield preserve_context_over_deferred(defer.gatherResults(
+        results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(get_key)(server_name, key_ids)
                 for server_name, key_ids in server_name_and_key_ids
             ],
             consumeErrors=True,
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         merged = {}
         for result in results:
@@ -485,7 +494,7 @@ class Keyring(object):
             for server_name, response_keys in processed_response.items():
                 keys.setdefault(server_name, {}).update(response_keys)
 
-        yield preserve_context_over_deferred(defer.gatherResults(
+        yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self.store_keys)(
                     server_name=server_name,
@@ -495,7 +504,7 @@ class Keyring(object):
                 for server_name, response_keys in keys.items()
             ],
             consumeErrors=True
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         defer.returnValue(keys)
 
@@ -543,7 +552,7 @@ class Keyring(object):
 
             keys.update(response_keys)
 
-        yield preserve_context_over_deferred(defer.gatherResults(
+        yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self.store_keys)(
                     server_name=key_server_name,
@@ -553,7 +562,7 @@ class Keyring(object):
                 for key_server_name, verify_keys in keys.items()
             ],
             consumeErrors=True
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         defer.returnValue(keys)
 
@@ -619,7 +628,7 @@ class Keyring(object):
         response_keys.update(verify_keys)
         response_keys.update(old_verify_keys)
 
-        yield preserve_context_over_deferred(defer.gatherResults(
+        yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self.store.store_server_keys_json)(
                     server_name=server_name,
@@ -632,7 +641,7 @@ class Keyring(object):
                 for key_id in updated_key_ids
             ],
             consumeErrors=True,
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
 
         results[server_name] = response_keys
 
@@ -710,7 +719,6 @@ class Keyring(object):
 
         defer.returnValue(verify_keys)
 
-    @defer.inlineCallbacks
     def store_keys(self, server_name, from_server, verify_keys):
         """Store a collection of verify keys for a given server
         Args:
@@ -721,7 +729,7 @@ class Keyring(object):
             A deferred that completes when the keys are stored.
         """
         # TODO(markjh): Store whether the keys have expired.
-        yield preserve_context_over_deferred(defer.gatherResults(
+        return logcontext.make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self.store.store_server_verify_key)(
                     server_name, server_name, key.time_added, key
@@ -729,4 +737,4 @@ class Keyring(object):
                 for key_id, key in verify_keys.items()
             ],
             consumeErrors=True,
-        )).addErrback(unwrapFirstError)
+        ).addErrback(unwrapFirstError))
diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py
index ed60d494ff..dac4b3f4e0 100644
--- a/synapse/handlers/device.py
+++ b/synapse/handlers/device.py
@@ -270,6 +270,8 @@ class DeviceHandler(BaseHandler):
             user_id (str)
             from_token (StreamToken)
         """
+        now_token = yield self.hs.get_event_sources().get_current_token()
+
         room_ids = yield self.store.get_rooms_for_user(user_id)
 
         # First we check if any devices have changed
@@ -280,11 +282,30 @@ class DeviceHandler(BaseHandler):
         # Then work out if any users have since joined
         rooms_changed = self.store.get_rooms_that_changed(room_ids, from_token.room_key)
 
+        member_events = yield self.store.get_membership_changes_for_user(
+            user_id, from_token.room_key, now_token.room_key
+        )
+        rooms_changed.update(event.room_id for event in member_events)
+
         stream_ordering = RoomStreamToken.parse_stream_token(
-            from_token.room_key).stream
+            from_token.room_key
+        ).stream
 
         possibly_changed = set(changed)
+        possibly_left = set()
         for room_id in rooms_changed:
+            current_state_ids = yield self.store.get_current_state_ids(room_id)
+
+            # The user may have left the room
+            # TODO: Check if they actually did or if we were just invited.
+            if room_id not in room_ids:
+                for key, event_id in current_state_ids.iteritems():
+                    etype, state_key = key
+                    if etype != EventTypes.Member:
+                        continue
+                    possibly_left.add(state_key)
+                continue
+
             # Fetch the current state at the time.
             try:
                 event_ids = yield self.store.get_forward_extremeties_for_room(
@@ -295,8 +316,6 @@ class DeviceHandler(BaseHandler):
                 # ordering: treat it the same as a new room
                 event_ids = []
 
-            current_state_ids = yield self.store.get_current_state_ids(room_id)
-
             # special-case for an empty prev state: include all members
             # in the changed list
             if not event_ids:
@@ -307,9 +326,25 @@ class DeviceHandler(BaseHandler):
                     possibly_changed.add(state_key)
                 continue
 
+            current_member_id = current_state_ids.get((EventTypes.Member, user_id))
+            if not current_member_id:
+                continue
+
             # mapping from event_id -> state_dict
             prev_state_ids = yield self.store.get_state_ids_for_events(event_ids)
 
+            # Check if we've joined the room? If so we just blindly add all the users to
+            # the "possibly changed" users.
+            for state_dict in prev_state_ids.itervalues():
+                member_event = state_dict.get((EventTypes.Member, user_id), None)
+                if not member_event or member_event != current_member_id:
+                    for key, event_id in current_state_ids.iteritems():
+                        etype, state_key = key
+                        if etype != EventTypes.Member:
+                            continue
+                        possibly_changed.add(state_key)
+                    break
+
             # If there has been any change in membership, include them in the
             # possibly changed list. We'll check if they are joined below,
             # and we're not toooo worried about spuriously adding users.
@@ -320,19 +355,30 @@ class DeviceHandler(BaseHandler):
 
                 # check if this member has changed since any of the extremities
                 # at the stream_ordering, and add them to the list if so.
-                for state_dict in prev_state_ids.values():
+                for state_dict in prev_state_ids.itervalues():
                     prev_event_id = state_dict.get(key, None)
                     if not prev_event_id or prev_event_id != event_id:
-                        possibly_changed.add(state_key)
+                        if state_key != user_id:
+                            possibly_changed.add(state_key)
                         break
 
-        users_who_share_room = yield self.store.get_users_who_share_room_with_user(
-            user_id
-        )
+        if possibly_changed or possibly_left:
+            users_who_share_room = yield self.store.get_users_who_share_room_with_user(
+                user_id
+            )
 
-        # Take the intersection of the users whose devices may have changed
-        # and those that actually still share a room with the user
-        defer.returnValue(users_who_share_room & possibly_changed)
+            # Take the intersection of the users whose devices may have changed
+            # and those that actually still share a room with the user
+            possibly_joined = possibly_changed & users_who_share_room
+            possibly_left = (possibly_changed | possibly_left) - users_who_share_room
+        else:
+            possibly_joined = []
+            possibly_left = []
+
+        defer.returnValue({
+            "changed": list(possibly_joined),
+            "left": list(possibly_left),
+        })
 
     @defer.inlineCallbacks
     def on_federation_query_user_devices(self, user_id):
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index b790a7c2ef..4669199b2d 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1606,7 +1606,7 @@ class FederationHandler(BaseHandler):
 
             context.rejected = RejectedReason.AUTH_ERROR
 
-        if event.type == EventTypes.GuestAccess:
+        if event.type == EventTypes.GuestAccess and not context.rejected:
             yield self.maybe_kick_guest_users(event)
 
         defer.returnValue(context)
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index d7b90a35ea..f2e4ffcec6 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -119,6 +119,16 @@ class GroupsSyncResult(collections.namedtuple("GroupsSyncResult", [
         return bool(self.join or self.invite or self.leave)
 
 
+class DeviceLists(collections.namedtuple("DeviceLists", [
+    "changed",   # list of user_ids whose devices may have changed
+    "left",      # list of user_ids whose devices we no longer track
+])):
+    __slots__ = []
+
+    def __nonzero__(self):
+        return bool(self.changed or self.left)
+
+
 class SyncResult(collections.namedtuple("SyncResult", [
     "next_batch",  # Token for the next sync
     "presence",  # List of presence events for the user.
@@ -296,6 +306,11 @@ class SyncHandler(object):
             timeline_limit = sync_config.filter_collection.timeline_limit()
             block_all_timeline = sync_config.filter_collection.blocks_all_room_timeline()
 
+            # Pull out the current state, as we always want to include those events
+            # in the timeline if they're there.
+            current_state_ids = yield self.state.get_current_state_ids(room_id)
+            current_state_ids = frozenset(current_state_ids.itervalues())
+
             if recents is None or newly_joined_room or timeline_limit < len(recents):
                 limited = True
             else:
@@ -307,6 +322,7 @@ class SyncHandler(object):
                     self.store,
                     sync_config.user.to_string(),
                     recents,
+                    always_include_ids=current_state_ids,
                 )
             else:
                 recents = []
@@ -342,6 +358,7 @@ class SyncHandler(object):
                     self.store,
                     sync_config.user.to_string(),
                     loaded_recents,
+                    always_include_ids=current_state_ids,
                 )
                 loaded_recents.extend(recents)
                 recents = loaded_recents
@@ -548,7 +565,8 @@ class SyncHandler(object):
         res = yield self._generate_sync_entry_for_rooms(
             sync_result_builder, account_data_by_room
         )
-        newly_joined_rooms, newly_joined_users = res
+        newly_joined_rooms, newly_joined_users, _, _ = res
+        _, _, newly_left_rooms, newly_left_users = res
 
         block_all_presence_data = (
             since_token is None and
@@ -562,7 +580,11 @@ class SyncHandler(object):
         yield self._generate_sync_entry_for_to_device(sync_result_builder)
 
         device_lists = yield self._generate_sync_entry_for_device_list(
-            sync_result_builder
+            sync_result_builder,
+            newly_joined_rooms=newly_joined_rooms,
+            newly_joined_users=newly_joined_users,
+            newly_left_rooms=newly_left_rooms,
+            newly_left_users=newly_left_users,
         )
 
         device_id = sync_config.device_id
@@ -635,25 +657,50 @@ class SyncHandler(object):
 
     @measure_func("_generate_sync_entry_for_device_list")
     @defer.inlineCallbacks
-    def _generate_sync_entry_for_device_list(self, sync_result_builder):
+    def _generate_sync_entry_for_device_list(self, sync_result_builder,
+                                             newly_joined_rooms, newly_joined_users,
+                                             newly_left_rooms, newly_left_users):
         user_id = sync_result_builder.sync_config.user.to_string()
         since_token = sync_result_builder.since_token
 
         if since_token and since_token.device_list_key:
-            room_ids = yield self.store.get_rooms_for_user(user_id)
-
-            user_ids_changed = set()
             changed = yield self.store.get_user_whose_devices_changed(
                 since_token.device_list_key
             )
-            for other_user_id in changed:
-                other_room_ids = yield self.store.get_rooms_for_user(other_user_id)
-                if room_ids.intersection(other_room_ids):
-                    user_ids_changed.add(other_user_id)
 
-            defer.returnValue(user_ids_changed)
+            # TODO: Be more clever than this, i.e. remove users who we already
+            # share a room with?
+            for room_id in newly_joined_rooms:
+                joined_users = yield self.state.get_current_user_in_room(room_id)
+                newly_joined_users.update(joined_users)
+
+            for room_id in newly_left_rooms:
+                left_users = yield self.state.get_current_user_in_room(room_id)
+                newly_left_users.update(left_users)
+
+            # TODO: Check that these users are actually new, i.e. either they
+            # weren't in the previous sync *or* they left and rejoined.
+            changed.update(newly_joined_users)
+
+            if not changed and not newly_left_users:
+                defer.returnValue(DeviceLists(
+                    changed=[],
+                    left=newly_left_users,
+                ))
+
+            users_who_share_room = yield self.store.get_users_who_share_room_with_user(
+                user_id
+            )
+
+            defer.returnValue(DeviceLists(
+                changed=users_who_share_room & changed,
+                left=set(newly_left_users) - users_who_share_room,
+            ))
         else:
-            defer.returnValue([])
+            defer.returnValue(DeviceLists(
+                changed=[],
+                left=[],
+            ))
 
     @defer.inlineCallbacks
     def _generate_sync_entry_for_to_device(self, sync_result_builder):
@@ -817,8 +864,8 @@ class SyncHandler(object):
             account_data_by_room(dict): Dictionary of per room account data
 
         Returns:
-            Deferred(tuple): Returns a 2-tuple of
-            `(newly_joined_rooms, newly_joined_users)`
+            Deferred(tuple): Returns a 4-tuple of
+            `(newly_joined_rooms, newly_joined_users, newly_left_rooms, newly_left_users)`
         """
         user_id = sync_result_builder.sync_config.user.to_string()
         block_all_room_ephemeral = (
@@ -849,7 +896,7 @@ class SyncHandler(object):
                     )
                     if not tags_by_room:
                         logger.debug("no-oping sync")
-                        defer.returnValue(([], []))
+                        defer.returnValue(([], [], [], []))
 
         ignored_account_data = yield self.store.get_global_account_data_by_type_for_user(
             "m.ignored_user_list", user_id=user_id,
@@ -862,7 +909,7 @@ class SyncHandler(object):
 
         if since_token:
             res = yield self._get_rooms_changed(sync_result_builder, ignored_users)
-            room_entries, invited, newly_joined_rooms = res
+            room_entries, invited, newly_joined_rooms, newly_left_rooms = res
 
             tags_by_room = yield self.store.get_updated_tags(
                 user_id, since_token.account_data_key,
@@ -870,6 +917,7 @@ class SyncHandler(object):
         else:
             res = yield self._get_all_rooms(sync_result_builder, ignored_users)
             room_entries, invited, newly_joined_rooms = res
+            newly_left_rooms = []
 
             tags_by_room = yield self.store.get_tags_for_user(user_id)
 
@@ -890,17 +938,30 @@ class SyncHandler(object):
 
         # Now we want to get any newly joined users
         newly_joined_users = set()
+        newly_left_users = set()
         if since_token:
             for joined_sync in sync_result_builder.joined:
                 it = itertools.chain(
-                    joined_sync.timeline.events, joined_sync.state.values()
+                    joined_sync.timeline.events, joined_sync.state.itervalues()
                 )
                 for event in it:
                     if event.type == EventTypes.Member:
                         if event.membership == Membership.JOIN:
                             newly_joined_users.add(event.state_key)
-
-        defer.returnValue((newly_joined_rooms, newly_joined_users))
+                        else:
+                            prev_content = event.unsigned.get("prev_content", {})
+                            prev_membership = prev_content.get("membership", None)
+                            if prev_membership == Membership.JOIN:
+                                newly_left_users.add(event.state_key)
+
+        newly_left_users -= newly_joined_users
+
+        defer.returnValue((
+            newly_joined_rooms,
+            newly_joined_users,
+            newly_left_rooms,
+            newly_left_users,
+        ))
 
     @defer.inlineCallbacks
     def _have_rooms_changed(self, sync_result_builder):
@@ -970,15 +1031,17 @@ class SyncHandler(object):
             mem_change_events_by_room_id.setdefault(event.room_id, []).append(event)
 
         newly_joined_rooms = []
+        newly_left_rooms = []
         room_entries = []
         invited = []
-        for room_id, events in mem_change_events_by_room_id.items():
+        for room_id, events in mem_change_events_by_room_id.iteritems():
             non_joins = [e for e in events if e.membership != Membership.JOIN]
             has_join = len(non_joins) != len(events)
 
             # We want to figure out if we joined the room at some point since
             # the last sync (even if we have since left). This is to make sure
             # we do send down the room, and with full state, where necessary
+            old_state_ids = None
             if room_id in joined_room_ids or has_join:
                 old_state_ids = yield self.get_state_at(room_id, since_token)
                 old_mem_ev_id = old_state_ids.get((EventTypes.Member, user_id), None)
@@ -996,6 +1059,26 @@ class SyncHandler(object):
             if not non_joins:
                 continue
 
+            # Check if we have left the room. This can either be because we were
+            # joined before *or* that we since joined and then left.
+            if events[-1].membership != Membership.JOIN:
+                if has_join:
+                    newly_left_rooms.append(room_id)
+                else:
+                    if not old_state_ids:
+                        old_state_ids = yield self.get_state_at(room_id, since_token)
+                        old_mem_ev_id = old_state_ids.get(
+                            (EventTypes.Member, user_id),
+                            None,
+                        )
+                        old_mem_ev = None
+                        if old_mem_ev_id:
+                            old_mem_ev = yield self.store.get_event(
+                                old_mem_ev_id, allow_none=True
+                            )
+                    if old_mem_ev and old_mem_ev.membership == Membership.JOIN:
+                        newly_left_rooms.append(room_id)
+
             # Only bother if we're still currently invited
             should_invite = non_joins[-1].membership == Membership.INVITE
             if should_invite:
@@ -1073,7 +1156,7 @@ class SyncHandler(object):
                     upto_token=since_token,
                 ))
 
-        defer.returnValue((room_entries, invited, newly_joined_rooms))
+        defer.returnValue((room_entries, invited, newly_joined_rooms, newly_left_rooms))
 
     @defer.inlineCallbacks
     def _get_all_rooms(self, sync_result_builder, ignored_users):
@@ -1322,6 +1405,7 @@ class SyncResultBuilder(object):
         self.archived = []
         self.device = []
         self.groups = None
+        self.to_device = []
 
 
 class RoomSyncResultBuilder(object):
diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py
index 803ac3e75b..b0d64aa6c4 100644
--- a/synapse/push/bulk_push_rule_evaluator.py
+++ b/synapse/push/bulk_push_rule_evaluator.py
@@ -20,6 +20,8 @@ from twisted.internet import defer
 from .push_rule_evaluator import PushRuleEvaluatorForEvent
 
 from synapse.api.constants import EventTypes, Membership
+from synapse.metrics import get_metrics_for
+from synapse.util.caches import metrics as cache_metrics
 from synapse.util.caches.descriptors import cached
 from synapse.util.async import Linearizer
 
@@ -31,6 +33,23 @@ logger = logging.getLogger(__name__)
 
 rules_by_room = {}
 
+push_metrics = get_metrics_for(__name__)
+
+push_rules_invalidation_counter = push_metrics.register_counter(
+    "push_rules_invalidation_counter"
+)
+push_rules_state_size_counter = push_metrics.register_counter(
+    "push_rules_state_size_counter"
+)
+
+# Measures whether we use the fast path of using state deltas, or if we have to
+# recalculate from scratch
+push_rules_delta_state_cache_metric = cache_metrics.register_cache(
+    "cache",
+    size_callback=lambda: 0,  # Meaningless size, as this isn't a cache that stores values
+    cache_name="push_rules_delta_state_cache_metric",
+)
+
 
 class BulkPushRuleEvaluator(object):
     """Calculates the outcome of push rules for an event for all users in the
@@ -41,6 +60,12 @@ class BulkPushRuleEvaluator(object):
         self.hs = hs
         self.store = hs.get_datastore()
 
+        self.room_push_rule_cache_metrics = cache_metrics.register_cache(
+            "cache",
+            size_callback=lambda: 0,  # There's not good value for this
+            cache_name="room_push_rule_cache",
+        )
+
     @defer.inlineCallbacks
     def _get_rules_for_event(self, event, context):
         """This gets the rules for all users in the room at the time of the event,
@@ -78,7 +103,10 @@ class BulkPushRuleEvaluator(object):
         # It's important that RulesForRoom gets added to self._get_rules_for_room.cache
         # before any lookup methods get called on it as otherwise there may be
         # a race if invalidate_all gets called (which assumes its in the cache)
-        return RulesForRoom(self.hs, room_id, self._get_rules_for_room.cache)
+        return RulesForRoom(
+            self.hs, room_id, self._get_rules_for_room.cache,
+            self.room_push_rule_cache_metrics,
+        )
 
     @defer.inlineCallbacks
     def action_for_event_by_user(self, event, context):
@@ -161,17 +189,19 @@ class RulesForRoom(object):
     the entire cache for the room.
     """
 
-    def __init__(self, hs, room_id, rules_for_room_cache):
+    def __init__(self, hs, room_id, rules_for_room_cache, room_push_rule_cache_metrics):
         """
         Args:
             hs (HomeServer)
             room_id (str)
             rules_for_room_cache(Cache): The cache object that caches these
                 RoomsForUser objects.
+            room_push_rule_cache_metrics (CacheMetric)
         """
         self.room_id = room_id
         self.is_mine_id = hs.is_mine_id
         self.store = hs.get_datastore()
+        self.room_push_rule_cache_metrics = room_push_rule_cache_metrics
 
         self.linearizer = Linearizer(name="rules_for_room")
 
@@ -213,11 +243,19 @@ class RulesForRoom(object):
         """
         state_group = context.state_group
 
+        if state_group and self.state_group == state_group:
+            logger.debug("Using cached rules for %r", self.room_id)
+            self.room_push_rule_cache_metrics.inc_hits()
+            defer.returnValue(self.rules_by_user)
+
         with (yield self.linearizer.queue(())):
             if state_group and self.state_group == state_group:
                 logger.debug("Using cached rules for %r", self.room_id)
+                self.room_push_rule_cache_metrics.inc_hits()
                 defer.returnValue(self.rules_by_user)
 
+            self.room_push_rule_cache_metrics.inc_misses()
+
             ret_rules_by_user = {}
             missing_member_event_ids = {}
             if state_group and self.state_group == context.prev_group:
@@ -225,8 +263,13 @@ class RulesForRoom(object):
                 # results.
                 ret_rules_by_user = self.rules_by_user
                 current_state_ids = context.delta_ids
+
+                push_rules_delta_state_cache_metric.inc_hits()
             else:
                 current_state_ids = context.current_state_ids
+                push_rules_delta_state_cache_metric.inc_misses()
+
+            push_rules_state_size_counter.inc_by(len(current_state_ids))
 
             logger.debug(
                 "Looking for member changes in %r %r", state_group, current_state_ids
@@ -273,6 +316,14 @@ class RulesForRoom(object):
                 yield self._update_rules_with_member_event_ids(
                     ret_rules_by_user, missing_member_event_ids, state_group, event
                 )
+            else:
+                # The push rules didn't change but lets update the cache anyway
+                self.update_cache(
+                    self.sequence,
+                    members={},  # There were no membership changes
+                    rules_by_user=ret_rules_by_user,
+                    state_group=state_group
+                )
 
         if logger.isEnabledFor(logging.DEBUG):
             logger.debug(
@@ -371,6 +422,7 @@ class RulesForRoom(object):
         self.state_group = object()
         self.member_map = {}
         self.rules_by_user = {}
+        push_rules_invalidation_counter.inc()
 
     def update_cache(self, sequence, members, rules_by_user, state_group):
         if sequence == self.sequence:
diff --git a/synapse/push/httppusher.py b/synapse/push/httppusher.py
index 8a5d473108..62c41cd9db 100644
--- a/synapse/push/httppusher.py
+++ b/synapse/push/httppusher.py
@@ -244,6 +244,26 @@ class HttpPusher(object):
 
     @defer.inlineCallbacks
     def _build_notification_dict(self, event, tweaks, badge):
+        if self.data.get('format') == 'event_id_only':
+            d = {
+                'notification': {
+                    'event_id': event.event_id,
+                    'room_id': event.room_id,
+                    'counts': {
+                        'unread': badge,
+                    },
+                    'devices': [
+                        {
+                            'app_id': self.app_id,
+                            'pushkey': self.pushkey,
+                            'pushkey_ts': long(self.pushkey_ts / 1000),
+                            'data': self.data_minus_url,
+                        }
+                    ]
+                }
+            }
+            defer.returnValue(d)
+
         ctx = yield push_tools.get_context_for_event(
             self.store, self.state_handler, event, self.user_id
         )
diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index ed7f1c89ad..630e92c90e 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -31,7 +31,7 @@ REQUIREMENTS = {
     "pyyaml": ["yaml"],
     "pyasn1": ["pyasn1"],
     "daemonize": ["daemonize"],
-    "py-bcrypt": ["bcrypt"],
+    "bcrypt": ["bcrypt"],
     "pillow": ["PIL"],
     "pydenticon": ["pydenticon"],
     "ujson": ["ujson"],
@@ -40,6 +40,7 @@ REQUIREMENTS = {
     "pymacaroons-pynacl": ["pymacaroons"],
     "msgpack-python>=0.3.0": ["msgpack"],
     "phonenumbers>=8.2.0": ["phonenumbers"],
+    "affinity": ["affinity"],
 }
 CONDITIONAL_REQUIREMENTS = {
     "web_client": {
diff --git a/synapse/rest/client/v1/admin.py b/synapse/rest/client/v1/admin.py
index 7d786e8de3..465b25033d 100644
--- a/synapse/rest/client/v1/admin.py
+++ b/synapse/rest/client/v1/admin.py
@@ -168,7 +168,7 @@ class ShutdownRoomRestServlet(ClientV1RestServlet):
 
     DEFAULT_MESSAGE = (
         "Sharing illegal content on this server is not permitted and rooms in"
-        " violatation will be blocked."
+        " violation will be blocked."
     )
 
     def __init__(self, hs):
@@ -296,7 +296,7 @@ class QuarantineMediaInRoom(ClientV1RestServlet):
 
 class ResetPasswordRestServlet(ClientV1RestServlet):
     """Post request to allow an administrator reset password for a user.
-    This need a user have a administrator access in Synapse.
+    This needs user to have administrator access in Synapse.
         Example:
             http://localhost:8008/_matrix/client/api/v1/admin/reset_password/
             @user:to_reset_password?access_token=admin_access_token
@@ -319,7 +319,7 @@ class ResetPasswordRestServlet(ClientV1RestServlet):
     @defer.inlineCallbacks
     def on_POST(self, request, target_user_id):
         """Post request to allow an administrator reset password for a user.
-        This need a user have a administrator access in Synapse.
+        This needs user to have administrator access in Synapse.
         """
         UserID.from_string(target_user_id)
         requester = yield self.auth.get_user_by_req(request)
@@ -343,7 +343,7 @@ class ResetPasswordRestServlet(ClientV1RestServlet):
 
 class GetUsersPaginatedRestServlet(ClientV1RestServlet):
     """Get request to get specific number of users from Synapse.
-    This need a user have a administrator access in Synapse.
+    This needs user to have administrator access in Synapse.
         Example:
             http://localhost:8008/_matrix/client/api/v1/admin/users_paginate/
             @admin:user?access_token=admin_access_token&start=0&limit=10
@@ -362,7 +362,7 @@ class GetUsersPaginatedRestServlet(ClientV1RestServlet):
     @defer.inlineCallbacks
     def on_GET(self, request, target_user_id):
         """Get request to get specific number of users from Synapse.
-        This need a user have a administrator access in Synapse.
+        This needs user to have administrator access in Synapse.
         """
         target_user = UserID.from_string(target_user_id)
         requester = yield self.auth.get_user_by_req(request)
@@ -395,7 +395,7 @@ class GetUsersPaginatedRestServlet(ClientV1RestServlet):
     @defer.inlineCallbacks
     def on_POST(self, request, target_user_id):
         """Post request to get specific number of users from Synapse..
-        This need a user have a administrator access in Synapse.
+        This needs user to have administrator access in Synapse.
         Example:
             http://localhost:8008/_matrix/client/api/v1/admin/users_paginate/
             @admin:user?access_token=admin_access_token
@@ -433,7 +433,7 @@ class GetUsersPaginatedRestServlet(ClientV1RestServlet):
 class SearchUsersRestServlet(ClientV1RestServlet):
     """Get request to search user table for specific users according to
     search term.
-    This need a user have a administrator access in Synapse.
+    This needs user to have administrator access in Synapse.
         Example:
             http://localhost:8008/_matrix/client/api/v1/admin/search_users/
             @admin:user?access_token=admin_access_token&term=alice
@@ -453,7 +453,7 @@ class SearchUsersRestServlet(ClientV1RestServlet):
     def on_GET(self, request, target_user_id):
         """Get request to search user table for specific users according to
         search term.
-        This need a user have a administrator access in Synapse.
+        This needs user to have a administrator access in Synapse.
         """
         target_user = UserID.from_string(target_user_id)
         requester = yield self.auth.get_user_by_req(request)
diff --git a/synapse/rest/client/v2_alpha/keys.py b/synapse/rest/client/v2_alpha/keys.py
index 6a3cfe84f8..943e87e7fd 100644
--- a/synapse/rest/client/v2_alpha/keys.py
+++ b/synapse/rest/client/v2_alpha/keys.py
@@ -188,13 +188,11 @@ class KeyChangesServlet(RestServlet):
 
         user_id = requester.user.to_string()
 
-        changed = yield self.device_handler.get_user_ids_changed(
+        results = yield self.device_handler.get_user_ids_changed(
             user_id, from_token,
         )
 
-        defer.returnValue((200, {
-            "changed": list(changed),
-        }))
+        defer.returnValue((200, results))
 
 
 class OneTimeKeyServlet(RestServlet):
diff --git a/synapse/rest/client/v2_alpha/sync.py b/synapse/rest/client/v2_alpha/sync.py
index 5f208a4c1c..a1e0e53b33 100644
--- a/synapse/rest/client/v2_alpha/sync.py
+++ b/synapse/rest/client/v2_alpha/sync.py
@@ -110,7 +110,7 @@ class SyncRestServlet(RestServlet):
         filter_id = parse_string(request, "filter", default=None)
         full_state = parse_boolean(request, "full_state", default=False)
 
-        logger.info(
+        logger.debug(
             "/sync: user=%r, timeout=%r, since=%r,"
             " set_presence=%r, filter_id=%r, device_id=%r" % (
                 user, timeout, since, set_presence, filter_id, device_id
@@ -189,7 +189,8 @@ class SyncRestServlet(RestServlet):
             "account_data": {"events": sync_result.account_data},
             "to_device": {"events": sync_result.to_device},
             "device_lists": {
-                "changed": list(sync_result.device_lists),
+                "changed": list(sync_result.device_lists.changed),
+                "left": list(sync_result.device_lists.left),
             },
             "presence": SyncRestServlet.encode_presence(
                 sync_result.presence, time_now
diff --git a/synapse/visibility.py b/synapse/visibility.py
index 5590b866ed..d7dbdc77ff 100644
--- a/synapse/visibility.py
+++ b/synapse/visibility.py
@@ -43,7 +43,8 @@ MEMBERSHIP_PRIORITY = (
 
 
 @defer.inlineCallbacks
-def filter_events_for_clients(store, user_tuples, events, event_id_to_state):
+def filter_events_for_clients(store, user_tuples, events, event_id_to_state,
+                              always_include_ids=frozenset()):
     """ Returns dict of user_id -> list of events that user is allowed to
     see.
 
@@ -54,6 +55,8 @@ def filter_events_for_clients(store, user_tuples, events, event_id_to_state):
             * the user has not been a member of the room since the
             given events
         events ([synapse.events.EventBase]): list of events to filter
+        always_include_ids (set(event_id)): set of event ids to specifically
+            include (unless sender is ignored)
     """
     forgotten = yield preserve_context_over_deferred(defer.gatherResults([
         defer.maybeDeferred(
@@ -91,6 +94,9 @@ def filter_events_for_clients(store, user_tuples, events, event_id_to_state):
         if not event.is_state() and event.sender in ignore_list:
             return False
 
+        if event.event_id in always_include_ids:
+            return True
+
         state = event_id_to_state[event.event_id]
 
         # get the room_visibility at the time of the event.
@@ -189,7 +195,8 @@ def filter_events_for_clients(store, user_tuples, events, event_id_to_state):
 
 
 @defer.inlineCallbacks
-def filter_events_for_client(store, user_id, events, is_peeking=False):
+def filter_events_for_client(store, user_id, events, is_peeking=False,
+                             always_include_ids=frozenset()):
     """
     Check which events a user is allowed to see
 
@@ -213,6 +220,7 @@ def filter_events_for_client(store, user_id, events, is_peeking=False):
         types=types
     )
     res = yield filter_events_for_clients(
-        store, [(user_id, is_peeking)], events, event_id_to_state
+        store, [(user_id, is_peeking)], events, event_id_to_state,
+        always_include_ids=always_include_ids,
     )
     defer.returnValue(res.get(user_id, []))