US Patent 8095618 In-memory caching of shared customizable multi-tenant data

In a multi-tenant data sharing environment with shared, customizable data attributes are assigned to requested data and stored in a cache store along with the requested data. For non-customized data designated as system data, one copy is stored in the cache store for use by multiple tenants allowing optimization of memory and performance for each data request/retrieval operation. A “delete sentinel” attribute may be assigned to non-existing data in the cache store enabling notification of requesting tenant(s) without a need to access the tenant data store each time a request for the non-existing data is received.