US Patent 11487665 Tiered caching of data in a storage system

A first read request for data stored at a non-volatile memory is received by a primary storage controller. The data is programmed from the non-volatile memory to a first cache of the primary storage controller, the first cache to store the data over a first time range. A second read request is received for the data. In response to receiving the second read request for the data, the data is programmed to a second cache to store the data over a second time range that is greater than the first time range. A notification is transmitted to a secondary storage controller, the notification including information associated with the programming of the data to the second cache.