diff --git a/config/datanode.example.toml b/config/datanode.example.toml
index 20f69e73aa..77c8dd7959 100644
--- a/config/datanode.example.toml
+++ b/config/datanode.example.toml
@@ -51,7 +51,7 @@ type = "File"
 # The local file cache directory
 # cache_path = "/path/local_cache"
 # The local file cache capacity in bytes.
-# cache_capacity = "256Mib"
+# cache_capacity = "256MB"
 
 # Compaction options, see `standalone.example.toml`.
 [storage.compaction]
diff --git a/config/standalone.example.toml b/config/standalone.example.toml
index 497b43f934..fec916f46f 100644
--- a/config/standalone.example.toml
+++ b/config/standalone.example.toml
@@ -118,7 +118,7 @@ type = "File"
 # Cache configuration for object storage such as 'S3' etc.
 # cache_path = "/path/local_cache"
 # The local file cache capacity in bytes.
-# cache_capacity = "256Mib"
+# cache_capacity = "256MB"
 
 # Compaction options.
 [storage.compaction]