Merge branch 'release-v0.18.6' into develop

4 files changed, 15 insertions, 70 deletions

diff --git a/synapse/__init__.py b/synapse/__init__.py
index 84592f53ea..fbb2bb57b0 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -16,4 +16,4 @@
 """ This is a reference implementation of a Matrix home server.
 """
 
-__version__ = "0.18.6-rc1"
+__version__ = "0.18.6-rc2"
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 6e23c207ee..6851f2376d 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -27,7 +27,6 @@ from synapse.util.caches.expiringcache import ExpiringCache
 from synapse.util.logutils import log_function
 from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
 from synapse.events import FrozenEvent
-from synapse.types import get_domain_from_id
 import synapse.metrics
 
 from synapse.util.retryutils import get_retry_limiter, NotRetryingDestination
@@ -741,8 +740,6 @@ class FederationClient(FederationBase):
             signed_events = yield self._check_sigs_and_hash_and_fetch(
                 destination, events, outlier=False
             )
-
-            have_gotten_all_from_destination = True
         except HttpResponseException as e:
             if not e.code == 400:
                 raise
@@ -750,72 +747,6 @@ class FederationClient(FederationBase):
             # We are probably hitting an old server that doesn't support
             # get_missing_events
             signed_events = []
-            have_gotten_all_from_destination = False
-
-        if len(signed_events) >= limit:
-            defer.returnValue(signed_events)
-
-        users = yield self.state.get_current_user_in_room(room_id)
-        servers = set(get_domain_from_id(u) for u in users)
-
-        servers = set(servers)
-        servers.discard(self.server_name)
-
-        failed_to_fetch = set()
-
-        while len(signed_events) < limit:
-            # Are we missing any?
-
-            seen_events = set(earliest_events_ids)
-            seen_events.update(e.event_id for e in signed_events if e)
-
-            missing_events = {}
-            for e in itertools.chain(latest_events, signed_events):
-                if e.depth > min_depth:
-                    missing_events.update({
-                        e_id: e.depth for e_id, _ in e.prev_events
-                        if e_id not in seen_events
-                        and e_id not in failed_to_fetch
-                    })
-
-            if not missing_events:
-                break
-
-            have_seen = yield self.store.have_events(missing_events)
-
-            for k in have_seen:
-                missing_events.pop(k, None)
-
-            if not missing_events:
-                break
-
-            # Okay, we haven't gotten everything yet. Lets get them.
-            ordered_missing = sorted(missing_events.items(), key=lambda x: x[0])
-
-            if have_gotten_all_from_destination:
-                servers.discard(destination)
-
-            def random_server_list():
-                srvs = list(servers)
-                random.shuffle(srvs)
-                return srvs
-
-            deferreds = [
-                preserve_fn(self.get_pdu)(
-                    destinations=random_server_list(),
-                    event_id=e_id,
-                )
-                for e_id, depth in ordered_missing[:limit - len(signed_events)]
-            ]
-
-            res = yield preserve_context_over_deferred(
-                defer.DeferredList(deferreds, consumeErrors=True)
-            )
-            for (result, val), (e_id, _) in zip(res, ordered_missing):
-                if result and val:
-                    signed_events.append(val)
-                else:
-                    failed_to_fetch.add(e_id)
 
         defer.returnValue(signed_events)
 
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 3fa7b2315c..f4c60e67e3 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -538,7 +538,16 @@ class FederationServer(FederationBase):
                 if get_missing and prevs - seen:
                     # If we're missing stuff, ensure we only fetch stuff one
                     # at a time.
+                    logger.info(
+                        "Acquiring lock for room %r to fetch %d missing events: %r...",
+                        pdu.room_id, len(prevs - seen), list(prevs - seen)[:5],
+                    )
                     with (yield self._room_pdu_linearizer.queue(pdu.room_id)):
+                        logger.info(
+                            "Acquired lock for room %r to fetch %d missing events",
+                            pdu.room_id, len(prevs - seen),
+                        )
+
                         # We recalculate seen, since it may have changed.
                         have_seen = yield self.store.have_events(prevs)
                         seen = set(have_seen.keys())
diff --git a/synapse/util/async.py b/synapse/util/async.py
index 16ed183d4c..4280455cbe 100644
--- a/synapse/util/async.py
+++ b/synapse/util/async.py
@@ -23,6 +23,10 @@ from synapse.util import unwrapFirstError
 
 from contextlib import contextmanager
 
+import logging
+
+logger = logging.getLogger(__name__)
+
 
 @defer.inlineCallbacks
 def sleep(seconds):
@@ -181,6 +185,7 @@ class Linearizer(object):
         self.key_to_defer[key] = new_defer
 
         if current_defer:
+            logger.info("Waiting to acquire linearizer lock for key %r", key)
             with PreserveLoggingContext():
                 yield current_defer