Methods and devices for cache management

A method for operating a storage device coupled to a host device, wherein the storage device comprises a first memory with first performance characteristics and a second memory with second performance characteristics, the method comprising:

• receiving, by the storage device from the host device, priority information identifying high priority data stored on the storage device, wherein:
• the high priority data was identified by the host device based on user interface identification of the high priority data stored on the storage device;
• periodically assigning increased priority to the high priority data based on a plurality of periodic messages from a driver of the storage device executing on the host device, wherein:
• an application that sends access requests for the high priority data has become idle, and
• the periodically assigning increased priority to the high priority data maintains increased priority of the high priority data when the high priority data has not been accessed over a period of time for which the application has been idle;
• identifying an idle period in which no requests from the host device are received by the storage device;
• and transferring, during the idle period, at least a portion of the high priority data from the first memory to the second memory.