diff --git a/Performance.md b/Performance.md
index 195fb04..2303557 100644
--- a/Performance.md
+++ b/Performance.md
@@ -77,7 +77,7 @@ ext3 (on tahoebs1) refuses to create more than 32000 subdirectories in a
 single parent directory. In 0.5.1, this appears as a limit on the number of
 buckets (one per storage index) that any [StorageServer](StorageServer) can hold. A simple
 nested directory structure will work around this.. the following code would
-let us manage 33.5G shares:
+let us manage 33.5G shares (see #150).
 
 ```
   from idlib import b2a