Safely remove a limited number of items from the cache_form table. This module provides a drush command drush safe-cache-form-clear that can be run at a high frequency, keeping the table at a reasonable size. It requires that you use the database cache back-end for the cache_form table. Drupal's core cron can have problems clearing out the cache_form table when it grows extremely large. This module works around this by limiting the number of items expired from the cache in a single run, dealing with a single manageable chunk at a time. You can configure the number of items deleted in a single run by setting the $conf['safe_cache_form_clear_limit'] persistent variable.