MDAC 2.5 SDK - OLE DB Programmer's Reference
Chapter 21: OLE DB for OLAP Concepts
Many clients need to retrieve schema information several times during the course of a session with the server. It is strongly recommended that clients cache the schema information from all schema rowsets except MEMBERS. Although caching schema rowset information results in a slightly larger working set for the application, the gain in performance far outweighs the increase in the working set.
For more information about MEMBERS rowsets, see "MEMBERS Rowset." For more information about working with schema information, see "Axis Rowsets" in Chapter 22 and "Retrieving Member Properties" in Chapter 24, "Multidimensional Expressions."