Improved nginx.conf and added comments

Stole some of the comments and configuration from the Nginx example
configuration shipped with "Unicorn". http://unicorn.bogomips.org/

nginx.conf

@@ -1,27 +1,49 @@
+# Default Nginx user for security reasons
 user       www www;
-worker_processes  5;
-error_log  logs/error.log;
-pid        logs/nginx.pid;
+
+# You generally only need one worker, unless you're serving
+# large amounts of static files which require blocking disk reads
+worker_processes 1;
+
 worker_rlimit_nofile 8192;
 
 events {
-  worker_connections  4096;
+  worker_connections  1024; # Increase if you have *a lot* of clients
+  accept_mutex off; # "on" if you have worker_processes > 1
+  # use epoll; # enable for Linux 2.6+
+  # use kqueue; # enable for *BSD (FreeBSD, OS X, ..)
 }
 
+# Change these to somewhere that suits you
+error_log  logs/error.log;
+pid        logs/nginx.pid;
+
 http {
+  # Set the mime-types
   include       mime.types;
+
+  # Fallback mime-type
   default_type  application/octet-stream;
+
+  # Format for our log files
   log_format   main '$remote_addr - $remote_user [$time_local]  $status '
     '"$request" $body_bytes_sent "$http_referer" '
     '"$http_user_agent" "$http_x_forwarded_for"';
+
+  # Click tracking!
   access_log   logs/access.log  main;
 
-  keepalive_timeout  65;
+  # ~2 seconds is often enough for HTML/CSS, but connections in
+  # Nginx are cheap, so generally it's safe to increase it
+  keepalive_timeout  5;
 
+  # You usually want to serve static files with Nginx
   sendfile on;
-  tcp_nopush on;
-  tcp_nodelay off;
 
+  tcp_nopush on; # off may be better for Comet/long-poll stuff
+  tcp_nodelay off; # on may be better for Comet/long-poll stuff
+
+  # Enable Gzip
   gzip  on;
   gzip_http_version 1.0;
   gzip_comp_level 2;
@@ -31,38 +53,42 @@ http {
   gzip_types text/html text/plain text/xml application/xml application/xml+rss text/css text/javascript application/javascript application/json;
 
   gzip_static on;
- 
+
   gzip_proxied        expired no-cache no-store private auth;
   gzip_disable        "MSIE [1-6]\.";
   gzip_vary           on;
 
   server {
-    listen 80 default deferred;
-    server_name example.com;
-    expires 1M;
+    # listen 80 default deferred; # for Linux
+    # listen 80 default accept_filter=httpready; # for FreeBSD
+    listen 80 default;
+
+    server_name _;
 
+    # Path for static files
     root /sites/example.com/public;
 
-    #static assets
-	location ~* ^.+\.(manifest)$ {
+    expires 1M;
+
+    # Static assets
+    location ~* ^.+\.(manifest)$ {
       expires -1D;
       root   /sites/example.com/public;
       access_log logs/static.log;
     }
+
     location ~* ^.+\.(ico|ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|css|rss|atom|js|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ {
-      # only set expires max IFF the file is a static file and exists
+      # Only set expires max IFF the file is a static file and exists
       if (-f $request_filename) {
         expires max;
         root   /sites/example.com/public;
         access_log logs/static.log;
       }
     }
-
   }
+
   server {
     server_name www.example.com;
     rewrite ^(.*) http://example.com$1 permanent;
   }
-
 }
-