怎么看nginx的gzip_static是否生效

我已经把gzip static module编译进去了，然后如下配置

gzip  on;
gzip_static on;
gzip_http_version 1.0;
gzip_disable "MSIE [1-6]\.";
gzip_vary on;

gzip_comp_level 2;
gzip_proxied any;
gzip_types text/plain text/html text/css application/x-javascript text/xml application/xml application/xml+rss text/javascript;

然后js和css的gz包也和源文件放到同个目录了，但是我日志里看不到对gz的访问，有没有什么方法可以确认，nginx确实使用gz包了？

---

curl -I -H "Accept-Encoding: gzip,deflate" http://.com/

HTTP/1.1 200 OK
Server: nginx/1.2.3
Date: Mon, 08 Oct 2012 09:14:20 GMT
Content-Type: text/html; charset=UTF-8
Connection: keep-alive
Vary: Accept-Encoding
Set-Cookie: sfsess=5072996cb0a46.21449a2b25cb6e546fe695a152ddc5b5; expires=Tue, 09-Oct-2012 09:14:20 GMT; path=/
Content-Encoding: gzip