The main issues concerning the size or content of a catalog are availability and recoverability, not performance. Catalog performance is normally unaffected by the size of the catalog, or by the aliases defined for it.

When deciding whether a catalog is too big or small, or whether it has the wrong combination of entries (based on catalog aliases), consider how loosing that catalog would affect your installation with respect to how long it would take to recover the catalog.

Splitting, merging, or reorganizing catalogs can be time-consuming and disruptive to your users. Therefore, only perform these actions after carefully weighing the possible benefits against the lost availability of the catalog.