US Patent 10180792 Cache management in data storage systems

Data storage devices may store selected data received from a data source to a buffer memory. The selected data may be copied from the buffer to a non-volatile memory configured for sequential storage. The selected data may then be copied from the buffer to a solid state memory, such as dynamic random access memory. The selected data may be copied from the solid state memory to a main store, such as a magnetic disc memory. If the selected data cannot be found in the solid state memory, the selected data in the non-volatile memory can be copied to the main store.