Freepbx Endpoint Manager (Commercial) Slow Paging Loading

I am experiencing very slow paging loading. The problem happens when I click on Extension Mapping. All other links work fine. It might take 10 to 15 minutes for this page to finish loading. I have changed /etc/php.d/freepbx.ini to 512M, Also updated /etc/php.ini to 512M. The problem start after I did a csv import. I have over 900 extension loaded.I imported 100 extensions at the time(very slow import). I have running Freepbx 2.11, EPM, Asterisk 11.5.0, php-5.3 and CentOS 6.4 X64.

Am I trying to manage to many extension?
Is there another file I should edit for memory limit?