Non-preemptive demand paging technique for NAND flash-based real-time embedded systems

NAND flash memory is utilized as code storage as well as for file system storage in consumer electronics. The demand paging technique for NAND flash code storage can reduce the required main memory space. However, in realtime systems, demand paging may invoke several problems, one such example is unpredictable timing behavior. Moreover, when NAND flash memory is used for both code storage and file system storage, the resource conflict issue needs to be resolved to allow for simultaneous accesses of demand paging and file system requests. This paper addresses several practical problems of NAND flash-based demand paging in real-time embedded systems and proposes a non-preemptive demand paging technique to resolve the resource conflict within non-preemptive critical sections. Experiments on a real mobile phone platform show that the proposed demand paging requires no significant overhead.