When F2FS meets address remapping

Abstract

While gaining popularity in mobile devices, F2FS, a flash-friendly variation of log-structured file system, reveals three drawbacks: segment cleaning overhead, metadata update overhead, and file fragmentation, which becomes conspicuous under random update workloads. This paper suggests for the first time to leverage the address-remap technique in flash storage to remedy such pitfalls in F2FS. Our approach can, while preserving the benefit of log-structured writes, achieve the eventual effect of in-place update, completely preventing three drawbacks of F2FS. It can thus significantly outperform ext4 as well as vanilla F2FS under random update workloads. Armed with another write mode, F2FS will become competitive for a wider range of applications.