As the number of file I/O intensive mobile applications increase, in-memory file systems have gained attention. In-memory file systems provide a fast access to file data, but the main memory of the corresponding mobile devices often suffers due to its capacity limit. To provide mobile applications with more free space, the swap mechanism has been an essential technique for the overcoming of this space insufficiency; however, the existing swap mechanism is inadequate for the file I/O of mobile applications. In this study, a new in-memory file system is devised to improve the current swap mechanism in the legacy in-memory file system, whereby strip-based layouts with separated file-swap partitions are used and unnecessary file- I/O overheads are eliminated. To evaluate the proposed in-memory file system, experiments with the file-I/O benchmark were conducted. The experiment results show that, compared to the current swap scheme, the proposed swap scheme improves the overall performance by ten times on average <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> .