1. A method, comprising: storing, on a computing system, application data in an in-memory cache for a plurality of namespaces, wherein the in-memory cache is configured to store data for a plurality of entries, including a particular entry associated with a particular one of the plurality of namespaces, wherein the particular entry is associated with a visibility parameter defining which of the plurality of namespaces have access to the particular entry; receiving, by the computing system, a request to access the particular entry in the in-memory cache, wherein the request is associated with a specified namespace of the plurality of namespaces, and wherein the request includes a key corresponding to the particular entry; and determining, based on the visibility parameter for the particular entry and the specified namespace, whether to provide access to the particular entry in response to the request.