1. In a computing environment with an application program, with a central cache, and with a cache service routine distinct from the application program, a method for the cache service routine to attempt to add data of interest to the central cache, the method comprising: receiving from the application program a request asking that the data of interest be added to the central cache; determining whether to add the data of interest to the central cache; and adding the data of interest to the central cache, in accordance with a determination to add the data of interest.