SQLSTATE[HY000] [1040] Too many connections

FILE: /www/wwwroot/zhongzhuang/Core/Library/Think/Db/Driver.class.php 　LINE: 109

#0 /www/wwwroot/zhongzhuang/Core/Library/Think/Db/Driver.class.php(109): E('SQLSTATE[HY000]...')
#1 /www/wwwroot/zhongzhuang/Core/Library/Think/Db/Driver.class.php(1064): Think\Db\Driver->connect()
#2 /www/wwwroot/zhongzhuang/Core/Library/Think/Db/Driver/Mysql.class.php(47): Think\Db\Driver->initConnect(true)
#3 /www/wwwroot/zhongzhuang/Core/Library/Think/Model.class.php(133): Think\Db\Driver\Mysql->getFields('db_lang')
#4 /www/wwwroot/zhongzhuang/Core/Library/Think/Model.class.php(121): Think\Model->flush()
#5 /www/wwwroot/zhongzhuang/Core/Library/Think/Model.class.php(1435): Think\Model->_checkTableInfo()
#6 /www/wwwroot/zhongzhuang/Core/Library/Think/Model.class.php(96): Think\Model->db(0, '', true)
#7 /www/wwwroot/zhongzhuang/Core/Common/functions.php(590): Think\Model->__construct('Lang')
#8 /www/wwwroot/zhongzhuang/Apps/Home/Controller/CommonController.class.php(21): D('Jzadmin/Lang')
#9 /www/wwwroot/zhongzhuang/Core/Library/Think/Controller.class.php(41): Home\Controller\CommonController->_initialize()
#10 /www/wwwroot/zhongzhuang/Core/Common/functions.php(705): Think\Controller->__construct()
#11 /www/wwwroot/zhongzhuang/Core/Library/Think/App.class.php(100): A('Empty')
#12 /www/wwwroot/zhongzhuang/Core/Library/Think/App.class.php(206): Think\App::exec()
#13 /www/wwwroot/zhongzhuang/Core/Library/Think/Think.class.php(120): Think\App::run()
#14 /www/wwwroot/zhongzhuang/Core/ThinkPHP.php(97): Think\Think::start()
#15 /www/wwwroot/zhongzhuang/index.php(21): require('/www/wwwroot/zh...')
#16 {main}