The swift-object-expirer daemon is responsible for deleting objects that have been set to be deleted after a specific period of time. If you aren't using this functionality in your environment it won't be needed.

You can read more about this feature at http://docs.openstack.org/developer/swift/overview_expiring_objects.html (http://docs.openstack.org/developer/s...) where a quick sample configuration file is also available.