thinkphp框架中系统内存储器溢出

thinkphp框架中系统内存溢出
数据量过大的页面就报错：Fatal error: Out of memory (allocated 1781792768) (tried to allocate 42 bytes) in C:\workspace\gshm_hrp\ThinkPHP\Lib\Think\Db\Driver\DbMysql.class.php on line 243


我修改了php.ini里面的配置：如下
max_execution_time = 0 ; Maximum execution time of each script, in seconds
max_input_time = 300 ; Maximum amount of time each script may spend parsing request data
memory_limit = 2048M ; Maximum amount of memory a script may consume (8MB)

请大神看看。