From cd80019eec69172f9753e0da25ad22d2f7c434db Mon Sep 17 00:00:00 2001
From: David Baker <dave@matrix.org>
Date: Fri, 22 Jan 2016 12:21:13 +0000
Subject: [PATCH] docs

---
 synapse/util/caches/lrucache.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/synapse/util/caches/lrucache.py b/synapse/util/caches/lrucache.py
index 5f9405c95f..cc6c25a712 100644
--- a/synapse/util/caches/lrucache.py
+++ b/synapse/util/caches/lrucache.py
@@ -28,7 +28,11 @@ def enumerate_leaves(node, depth):
 
 
 class LruCache(object):
-    """Least-recently-used cache."""
+    """
+    Least-recently-used cache.
+    Supports del_multi only if cache_type=TreeCache
+    If cache_type=TreeCache, all keys must be tuples.
+    """
     def __init__(self, max_size, keylen=1, cache_type=dict):
         cache = cache_type()
         self.size = 0