Optimised Linux swap system for flash memory

Proposed is an optimised Linux swap system, called SGBI, where the Linux kernel manages the flash memory-based swap area directly without FTL. This approach not only introduces an efficient swap-aware garbage collection policy to reduce its cleaning cost and improve the degree of wear-levelling, but also adopts an efficient swap-in read-ahead scheme to delay the execution of garbage collection. Swap I/O traces from the Linux kernel have been collected and trace-driven simulations performed, which show that the proposed approach greatly outperforms existing Linux swap systems.