diff --git a/docs/notes/note.md b/docs/notes/note.md
index 6d535f6..371182a 100644
--- a/docs/notes/note.md
+++ b/docs/notes/note.md
@@ -96,3 +96,8 @@ make
 
 - stop system service not used
 - Run script in /dev/shm
+
+```
+cat /sys/block/sda/queue/scheduler
+echo xxx > /sys/block/sda/queue/scheduler
+```