I have developed custom import module in my Magento store. It works normally on localhost, but on a server as not expected. I send csv data sheet using post form and on module backend it should display products of csv sheet in grid. Response status 200 Ok, but grid is not loaded completely (response html also, there is no footer, grid js scripts), for example only 35 percent of grid. See attached image:

I cant figure out this issue related to Magento or PHP/Server configuration. Anybody have some suggestion?
What does import module after uploading csv? It parses csv and stores array of product related data (attribute values, option values) in session. If I test csv data sheet with less data it works normally, fails only when count of products are more.