If you use the directory-only cache method, you only write updates to permanent storage. You do not write data to the cache structure and, as a result, do not need to issue requests for cast out. To write the data item to permanent storage, use the access method that you normally use to access permanent storage. Immediately before or after you write the data item to permanent storage, ensure that you invalidate copies of the data item that other users maintain in their local cache buffers by using IXLCACHE REQUEST=CROSS_INVAL. The CROSS_INVAL request must be invoked under the same serialization used to update the data item.