Symfony任务意外内存

I am using Symfony task php5.2. Here is a portion of my code:

array of images

foreach($array as $k=>$v)
{
    abc(); // function call which will cope images from one server to another
           // by using file_get_content in a php variable and using api(wso).
    echo memory_get_usage();
}

problem is memory_get_usage(); always returning same value but when i am using top command memory is increasing nonstop.

Is there any bug in symfony task or php5.2 or wso.

Have you tried memory_get_usage(true)?

Also, have you considered that it might not be PHP that is using the memory? But some other library you are using?