Views, Display Suite - fatal error on allowed memory size - what could be happening?
The PHP memory limit is being exceeded. In your drupal site, go to /admin/reports/status/php and look for "Loaded Configuration File". It should be one of the first 5 columns in the table.  In a plain text editor, or a code editor, open the file listed there. In it, search for memory_limit and replace the value next to it with, say, `128M'. Save that file and restart your web server. You may need to increase the memory limit again, if your server still errors out.