http://brainspl.at/articles/2007/01/03/new-nginx-conf-with-optimizations

# user and group to run as
user  ez ez;

# number of nginx workers
worker_processes  6;

# pid of nginx master process
pid /var/run/nginx.pid;

# Number of worker connections. 1024 is a good default
events {
  worker_connections 1024;
}

# start the http module where we config http access.
http {
  # pull in mime-types. You can break out your config
  # into as many include's as you want to make it cleaner
  include /etc/nginx/mime.types;

  # set a default type for the rare situation that
  # nothing matches from the mimie-type include
  default_type  application/octet-stream;

  # configure log format
  log_format main '$remote_addr - $remote_user [$time_local] '
                  '"$request" $status  $body_bytes_sent "$http_referer" '
                  '"$http_user_agent" "$http_x_forwarded_for"';

  # main access log
  access_log  /var/log/nginx_access.log  main;

  # main error log
  error_log  /var/log/nginx_error.log debug;

  # no sendfile on OSX
  sendfile on;

  # These are good default values.
  tcp_nopush        on;
  tcp_nodelay       off;
  # output compression saves bandwidth
  gzip            on;
  gzip_http_version 1.0;
  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;


  # this is where you define your mongrel clusters.
  # you need one of these blocks for each cluster
  # and each one needs its own name to refer to it later.
  upstream mongrel {
    server 127.0.0.1:5000;
    server 127.0.0.1:5001;
    server 127.0.0.1:5002;
  }


  # the server directive is nginx's virtual host directive.
  server {
    # port to listen on. Can also be set to an IP:PORT
    listen 80;
   
    # Set the max size for file uploads to 50Mb
    client_max_body_size 50M;

    # sets the domain[s] that this vhost server requests for
    # server_name www.[engineyard].com [engineyard].com;

    # doc root
    root /data/ez/current/public;

    # vhost specific access log
    access_log  /var/log/nginx.vhost.access.log  main;

    # this rewrites all the requests to the maintenance.html
    # page if it exists in the doc root. This is for capistrano's
    # disable web task
    if (-f $document_root/system/maintenance.html) {
      rewrite  ^(.*)$  /system/maintenance.html last;
      break;
    }

    location / {
      # needed to forward user's IP address to rails
      proxy_set_header  X-Real-IP  $remote_addr;

      # needed for HTTPS
      proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_redirect false;
      proxy_max_temp_file_size 0;
     
      # If the file exists as a static file serve it directly without
      # running all the other rewite tests on it
      if (-f $request_filename) {
        break;
      }

      # check for index.html for directory index
      # if its there on the filesystem then rewite
      # the url to add /index.html to the end of it
      # and then break to send it to the next config rules.
      if (-f $request_filename/index.html) {
        rewrite (.*) $1/index.html break;
      }

      # this is the meat of the rails page caching config
      # it adds .html to the end of the url and then checks
      # the filesystem for that file. If it exists, then we
      # rewite the url to have explicit .html on the end
      # and then send it on its way to the next config rule.
      # if there is no file on the fs then it sets all the
      # necessary headers and proxies to our upstream mongrels
      if (-f $request_filename.html) {
        rewrite (.*) $1.html break;
      }

      if (!-f $request_filename) {
        proxy_pass http://mongrel;
        break;
      }
    }

    error_page   500 502 503 504  /500.html;
    location = /500.html {
      root   /data/ez/current/public;
    }
  }

  # This server is setup for ssl. Uncomment if
  # you are using ssl as well as port 80.
  server {
    # port to listen on. Can also be set to an IP:PORT
    listen 443;
   
    # Set the max size for file uploads to 50Mb
    client_max_body_size 50M;

    # sets the domain[s] that this vhost server requests for
    # server_name www.[engineyard].com [engineyard].com;

    # doc root
    root /data/ez/current/public;

    # vhost specific access log
    access_log  /var/log/nginx.vhost.access.log  main;

    # this rewrites all the requests to the maintenance.html
    # page if it exists in the doc root. This is for capistrano's
    # disable web task
    if (-f $document_root/system/maintenance.html) {
      rewrite  ^(.*)$  /system/maintenance.html last;
      break;
    }

    location / {
      # needed to forward user's IP address to rails
      proxy_set_header  X-Real-IP  $remote_addr;

      # needed for HTTPS
      proxy_set_header X_FORWARDED_PROTO https;

      proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_redirect false;
      proxy_max_temp_file_size 0;
     
      # If the file exists as a static file serve it directly without
      # running all the other rewite tests on it
      if (-f $request_filename) {
        break;
      }

      # check for index.html for directory index
      # if its there on the filesystem then rewite
      # the url to add /index.html to the end of it
      # and then break to send it to the next config rules.
      if (-f $request_filename/index.html) {
        rewrite (.*) $1/index.html break;
      }

      # this is the meat of the rails page caching config
      # it adds .html to the end of the url and then checks
      # the filesystem for that file. If it exists, then we
      # rewite the url to have explicit .html on the end
      # and then send it on its way to the next config rule.
      # if there is no file on the fs then it sets all the
      # necessary headers and proxies to our upstream mongrels
      if (-f $request_filename.html) {
        rewrite (.*) $1.html break;
      }

      if (!-f $request_filename) {
        proxy_pass http://mongrel;
        break;
      }
    }

    error_page   500 502 503 504  /500.html;
    location = /500.html {
      root   /data/ez/current/public;
    }
  }


}