Nginx 1.1.4 开发版改进内容：
*) Feature: the ngx_http_upstream_keepalive module. *) Feature: the "proxy_http_version" directive. *) Feature: the "fastcgi_keep_conn" directive. *) Feature: the "worker_aio_requests" directive. *) Bugfix: if nginx was built --with-file-aio it could not be run on Linux kernel which did not support AIO. *) Bugfix: in Linux AIO error processing. *) Bugfix: reduced memory consumption for long-lived requests. *) Bugfix: the module ngx_http_mp4_module did not support 64-bit MP4 "co64" atom.