field_purge_batch($batch_size, $field_storage_uuid = NULL)
Purges a batch of deleted Field API data, field storages, or fields.
This function will purge deleted field data in batches. The batch size is defined as an argument to the function, and once each batch is finished, it continues with the next batch until all have completed. If a deleted field with no remaining data records is found, the field itself will be purged. If a deleted field storage with no remaining fields is found, the field