US Patent 11650920 Write cache management

A storage control system maintains a write cache in a non-volatile memory device of primary memory of a storage node. The write cache comprises a cyclic buffer and pointers to manage the write cache and track a tail location and head location of the write cache. The storage control system receives a write request from a host system, which comprises a data item to be written to primary storage. The received data item is written together with an associated metadata item at the head location of the write cache. The items in the write cache are arranged in a cyclic write order from the tail location to the head location. The storage control system sends an acknowledgment to the host system that the data item is successfully written to the primary storage, in response to the received data item and the associated metadata item being stored in the write cache.