php-cgi.php just hang and die on a very low load. To fix this, use spawn-php

Install

ActivePython-2.7.2.5-win64-x64.msi
pywin32-217.win-amd64-py2.7.exe

Change nginx configuration worker_processes 1;

events {
  worker_connections  1024;
}

http {
  include       mime.types;
  default_type  application/octet-stream;
  sendfile        on;
  keepalive_timeout  65;

  upstream php_farm {
   server 127.0.0.1:9000 weight=1;
   server 127.0.0.1:9001 weight=1;
   server 127.0.0.1:9002 weight=1;
   server 127.0.0.1:9003 weight=1;
   server 127.0.0.1:9004 weight=1;
   server 127.0.0.1:9005 weight=1;
   server 127.0.0.1:9006 weight=1;
   server 127.0.0.1:9007 weight=1;
   server 127.0.0.1:9008 weight=1;
   server 127.0.0.1:9009 weight=1;
  }


server {
  listen       80;
  server_name  localhost;
  location / {
   root   html;
   index  index.php index.html index.htm;
  }

  error_page   500 502 503 504  /50x.html;
   location = /50x.html {
   root   html;
  }
 
  location ~ \.php$ {
   root           html;
   fastcgi_pass   php_farm;
   fastcgi_index  index.php;
   fastcgi_param  SCRIPT_FILENAME  c:/nginx/html/$fastcgi_script_name;
   include        fastcgi_params;
  }
}