Number of physical writes of temporary pages: <count>
When temporary data pages are generated to build (buffer) result sets (in JOINS or ORDER BY statements, for example), the data cache is not large enough to accommodate the temporary pages, which have to be moved into the data area. However, these pages must be exported out of the data area again for the further processing of the SQL statement.
Find the statement that causes these large (buffer) result sets to be created, and check the access strategies for this statement.
For information on creating optimized SQL statements, see the SQL Optimizer documentation.