如何使用Nginx和Passenger设置代理caching

我使用Nginx和Passenger作为我的Rails应用程序。 我想使用代理caching来caching我的网页。 但是，每个请求都直接导入到我的rails应用程序中。 我不知道我的configuration有什么问题。 以下是我的configuration：

user www-data; worker_processes 1; events { worker_connections 1024; } http { passenger_root /usr/lib/ruby/gems/1.8/gems/passenger-2.2.15; passenger_ruby /usr/bin/ruby1.8; passenger_max_pool_size 6; passenger_max_instances_per_app 1; passenger_pool_idle_time 0; rails_spawn_method conservative; include mime.types; default_type application/octet-stream; server_names_hash_bucket_size 512; sendfile on; #tcp_nopush on; keepalive_timeout 65; tcp_nodelay on; gzip on; gzip_http_version 1.0; gzip_vary on; gzip_comp_level 6; gzip_proxied any; gzip_types text/plain text/css text/javascript application/javascript application/json application/x-javascript text/xml application/xml application/xml+rss; proxy_cache_path /var/www/cache/webapp levels=1:2 keys_zone=webapp:8m max_size=1000m inactive=600m; include vhosts/*.conf; include /opt/nginx/conf/sites-enabled/*; root /var/www; } server { listen 127.0.0.1:3008; server_name localhost; root /var/www/yoolk_web_app/public; # <--- be sure to point to 'public'! passenger_enabled on; rails_env development; passenger_use_global_queue on; } server { listen 80; server_name webpage.dev; proxy_set_header X-Real-IP $remote_addr; proxy_set_header Host $host; error_page 503 http://$host/maintenance.html; location ~* (css|js|png|jpe?g|gif|ico)$ { root /var/www/web_app/public; expires max; } location / { proxy_pass http://127.0.0.1:3008/; proxy_cache webapp; proxy_cache_valid 200 10m; } #More Location } 

 proxy_cache_lock on; proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504; proxy_ignore_headers Expires Cache-Control; proxy_cache_revalidate off;