diff --git a/configuration/kresd.conf b/configuration/kresd.conf
index 527d72e..03af617 100644
--- a/configuration/kresd.conf
+++ b/configuration/kresd.conf
@@ -15,6 +15,7 @@ modules = {
 }
 
 -- Cache size https://knot-resolver.readthedocs.io/en/stable/daemon-bindings-cache.html#sizing
+-- "For personal and small office use-cases cache size around 100 MB is more than enough." -cz.nic
 cache.size = 100 * MB
 
 -- policy help : https://knot-resolver.readthedocs.io/en/stable/modules-policy.html