swift:http://my.oschina.net/zhouxingxing
http://blog.csdn.net/lynn_kong/article/details/8083924
http://manual.blog.51cto.com/#
http://docs.openstack.org/developer/nova/devref/index.html
http://ken.pepple.info/openstack/2011/04/22/openstack-nova-architecture/