diff --git a/docker.yml b/docker.yml
index 08aeed8..2ce83d5 100644
--- a/docker.yml
+++ b/docker.yml
@@ -121,7 +121,7 @@
           MARIADB_RANDOM_ROOT_PASSWORD=1
           MARIADB_AUTO_UPGRADE=1
           MARIADB_INITDB_SKIP_TZINFO=1
-          # from here: save memory
+          # from here: save memory https://techroads.org/reducing-memory-use-on-my-mariadb-mysql-wordpress-docker-stack/
           MARIADB_KEY_BUFFER_SIZE=1M
           MARIADB_MYISAMCHK_KEY_BUFFER_SIZE=1M
           MARIADB_INNODB_BUFFER_POOL_SIZE=10M