1. A method for managing data within a Redundant Array of Independent Disks (RAID) array utilizing a RAID controller including an extended cache, comprising: storing contentual metadata of the extended cache within the extended cache; approximating the contentual metadata of the extended cache utilizing a counting Bloom filter; storing the counting Bloom filter within a primary cache; storing contentual metadata of the primary cache within the primary cache; executing one of a data read or a data write without accessing the contentual metadata of the extended cache stored within the extended cache; determining one of a presence or an absence of a first data set within the primary cache utilizing the contentual metadata stored within the primary cache upon receiving a request for at least one of the data read or the data write; and utilizing the counting Bloom filter to determine one of the presence or the absence of the first data set within the extended cache upon determining the absence of the data set within the primary cache.