message: add doc for change
diff: @@ -167,3 +167,4 @@ curl http://127.0.0.1:8888/v1/chain/get_info
  docker-compose logs nodeosd
  ```
  +The `blocks` data are stored under `--data-dir` by default, and the wallet files are stored under `--wallet-dir` by default, of course you can change these as you want.
  \ No newline at end of file
  