From 9481707a52a89022bc5d99c181ceb9e7ec9ec9e9 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Fri, 5 Jul 2019 11:10:19 +0100
Subject: Fixes to the federation rate limiter (#5621)

- Put the default window_size back to 1000ms (broken by #5181)
- Make the `rc_federation` config actually do something
- fix an off-by-one error in the 'concurrent' limit
- Avoid creating an unused `_PerHostRatelimiter` object for every single
  incoming request
---
 synapse/config/ratelimiting.py |  4 ++--
 synapse/util/ratelimitutils.py | 16 ++++++++--------
 2 files changed, 10 insertions(+), 10 deletions(-)

(limited to 'synapse')

diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 8c587f3fd2..33f31cf213 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -23,7 +23,7 @@ class RateLimitConfig(object):
 
 class FederationRateLimitConfig(object):
     _items_and_default = {
-        "window_size": 10000,
+        "window_size": 1000,
         "sleep_limit": 10,
         "sleep_delay": 500,
         "reject_limit": 50,
@@ -54,7 +54,7 @@ class RatelimitConfig(Config):
 
         # Load the new-style federation config, if it exists. Otherwise, fall
         # back to the old method.
-        if "federation_rc" in config:
+        if "rc_federation" in config:
             self.rc_federation = FederationRateLimitConfig(**config["rc_federation"])
         else:
             self.rc_federation = FederationRateLimitConfig(
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index 27bceac00e..5ca4521ce3 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -36,9 +36,11 @@ class FederationRateLimiter(object):
             clock (Clock)
             config (FederationRateLimitConfig)
         """
-        self.clock = clock
-        self._config = config
-        self.ratelimiters = {}
+
+        def new_limiter():
+            return _PerHostRatelimiter(clock=clock, config=config)
+
+        self.ratelimiters = collections.defaultdict(new_limiter)
 
     def ratelimit(self, host):
         """Used to ratelimit an incoming request from given host
@@ -53,11 +55,9 @@ class FederationRateLimiter(object):
             host (str): Origin of incoming request.
 
         Returns:
-            _PerHostRatelimiter
+            context manager which returns a deferred.
         """
-        return self.ratelimiters.setdefault(
-            host, _PerHostRatelimiter(clock=self.clock, config=self._config)
-        ).ratelimit()
+        return self.ratelimiters[host].ratelimit()
 
 
 class _PerHostRatelimiter(object):
@@ -122,7 +122,7 @@ class _PerHostRatelimiter(object):
         self.request_times.append(time_now)
 
         def queue_request():
-            if len(self.current_processing) > self.concurrent_requests:
+            if len(self.current_processing) >= self.concurrent_requests:
                 queue_defer = defer.Deferred()
                 self.ready_request_queue[request_id] = queue_defer
                 logger.info(
-- 
cgit 1.4.1