1 files changed, 13 insertions, 3 deletions
diff --git a/synapse/util/caches/__init__.py b/synapse/util/caches/__init__.py
index 183faf75a1..7b065b195e 100644
--- a/synapse/util/caches/__init__.py
+++ b/synapse/util/caches/__init__.py
@@ -13,15 +13,25 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from prometheus_client.core import Gauge, REGISTRY, GaugeMetricFamily
-
 import os
 
-from six.moves import intern
 import six
+from six.moves import intern
+
+from prometheus_client.core import REGISTRY, Gauge, GaugeMetricFamily
 
 CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.5))
 
+
+def get_cache_factor_for(cache_name):
+    env_var = "SYNAPSE_CACHE_FACTOR_" + cache_name.upper()
+    factor = os.environ.get(env_var)
+    if factor:
+        return float(factor)
+
+    return CACHE_SIZE_FACTOR
+
+
 caches_by_name = {}
 collectors_by_name = {}