This module is used to delete all content and/or users from a site. This is mainly a developer tool, which can come in handy in several case.
https://www.drupal.org/project/delete_all
as will as the Bulk Delete module will delete any nodes of a certain node-type using the batch api. It is advised to use the Views Batch Operations module (VBO) for a small number of nodes. But if you have to delete 10.000 nodes this module might be a better option.