diff --git a/Optimization.md b/Optimization.md
index 9fe9992..c3267ad 100644
--- a/Optimization.md
+++ b/Optimization.md
@@ -146,5 +146,5 @@ When going to production, you will want to collect the logs. SeaweedFS uses glog
 
 ```bash
 weed -v=2 master
-weed -log_dir=. volume
+weed -logdir=. volume
 ```