修改linux最大打开文件数

http://hi.baidu.com/lybadmin/blog/item/2f0cfd6ed3311ed580cb4ab9.html

http://blog.youkuaiyun.com/flcandclf/article/details/1740173

http://baike.baidu.com/view/1520054.htm

http://news.newhua.com/news1/safe_technology/2008/115/08115133337E38GCKGB2EK97407F66878C384K95BDH4J1KH36ECBFJ8_4.html?lt=common