Do not build more than 500 aggregations for a partition
This rule analyzes partitions to determine whether there are too many aggregations.
For best performance, you should typically avoid building too many aggregations. If you build too many aggregations, it can adversely affect performance by increasing the search space during queries and increasing the work necessary during processing. As a rule, do not build more than 500 aggregations per partition.
For more information about how to design aggregations, see Designing Partition Storage and Aggregations in SQL Server Books Online.
For performance issues related to aggregations, partitions, and multiple aggregation designs, see the section, "Aggregation considerations for multiple partitions," in the SQL Server 2005 Analysis Services Performance Guide.