Garbage collection policy for flash-aware Linux swap system

Proposed is a swap-aware garbage collection policy, called SCATA, for a flash-aware Linux swap system. SCATA not only introduces an improved victim block selection method to reduce cleaning cost and improve the degree of wear-levelling, but also redefines the concept of hot page and cold page according to the least-recently-used page replacement algorithm and clusters hot pages separately from cold pages, and then redistributes them to different free blocks during the migration step of garbage collection operation to reduce cleaning cost and obtain much more free space. Swap I/O traces from the Linux kernel have been collected and trace-driven simulations performed, which show that the proposed policy greatly outperforms existing garbage collection policies.