docs: tip for gzip compression

website/docs/en/config/performance/print-file-size.mdx

@@ -106,6 +106,10 @@ export default {
 };
 ```
 
+:::tip
+This data is only for reference to the size after gzip compression. Rsbuild does not enable gzip compression for static assets. Usually, you need to enable gzip compression on the server side, for example, using the [gzip module](https://nginx.org/en/docs/http/ngx_http_gzip_module.html) of nginx.
+:::
+
 ### include
 
 - **Type:**

website/docs/zh/config/performance/print-file-size.mdx

@@ -106,6 +106,10 @@ export default {
 };
 ```
 
+:::tip
+该数据仅用于参考 gzip 压缩后的体积，Rsbuild 并不会对静态资源开启 gzip 压缩。通常，你需要在服务器端开启 gzip 压缩，例如使用 [nginx 的 gzip 模块](https://nginx.org/en/docs/http/ngx_http_gzip_module.html)。
+:::
+
 ### include
 
 - **类型：**