SQLSTATE[08004] [1040] Too many connections

FILE: /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Db/Driver.class.php 　LINE: 109

#0 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Db/Driver.class.php(109): E('SQLSTATE[08004]...')
#1 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Db/Driver.class.php(1064): Think\Db\Driver->connect()
#2 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Db/Driver/Mysql.class.php(47): Think\Db\Driver->initConnect(true)
#3 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Model.class.php(134): Think\Db\Driver\Mysql->getFields('tb_papertrans')
#4 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Model.class.php(122): Think\Model->flush()
#5 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Model.class.php(1450): Think\Model->_checkTableInfo()
#6 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Model.class.php(97): Think\Model->db(0, '', true)
#7 /www/wwwroot/www.pindex.cn/ThinkPHP/Common/functions.php(621): Think\Model->__construct('papertrans', '', '')
#8 /www/wwwroot/www.pindex.cn/Application/Home/Controller/IndexController.class.php(205): M('papertrans')
#9 [internal function]: Home\Controller\IndexController->n()
#10 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/App.class.php(164): ReflectionMethod->invoke(Object(Home\Controller\IndexController))
#11 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/App.class.php(202): Think\App::exec()
#12 /www/wwwroot/www.pindex.cn/ThinkPHP/Library/Think/Think.class.php(120): Think\App::run()
#13 /www/wwwroot/www.pindex.cn/ThinkPHP/ThinkPHP.php(97): Think\Think::start()
#14 /www/wwwroot/www.pindex.cn/index.php(24): require('/www/wwwroot/ww...')
#15 {main}