Binding and unbinding objects may have an impact on performance.
The object’s pages are flushed from the cache – When you bind an object or database to a cache, the object’s pages that are already in memory are removed from the source cache. The next time the pages are needed by a query, they are read into the new cache. Similarly, when you unbind objects, the pages in cache are removed from the user-configured cache and read into the default cache the next time they are needed by a query.
The object must be locked to perform the binding – To bind or unbind user tables, indexes, or text or image objects, the cache binding commands must have an exclusive table lock on the object. If a user holds locks on a table, and you issue sp_bindcache, sp_unbindcache, or sp_unbindcache_all on the object, the system procedure sleeps until it can acquire the locks it needs
For databases, system tables, and indexes on system tables, the database must be in single-user mode, so there cannot be another user who holds a lock on the object.
All query plans for procedures and triggers must be recompiled – Cache bindings and I/O sizes are part of the query plan for stored procedures and triggers. When you change the cache binding for an object, all the stored procedures that reference the object are recompiled the next time they are executed. When you change the cache binding for a database, all stored procedures that reference any objects in the database that are not explicitly bound to a cache are recompiled the next time they are run