Using UBI

UBI and UBIFS

UBI is the Unsorted Block Images layer, and is an erase block management layer. UBI serves two purposes, tracking NAND bad blocks and providing wear leveling. While it is possible to run a traditional flash filesystem on top of UBI, it is not recommended. UBIFS was written with UBI in mind and is able to take full advantage of what UBI provides. UBIFS has multiple advantages over JFFS2, UBIFS supports write caching, UBIFS performs better on larger NAND devices, mounts faster, allows for quicker access to large files, improved write speeds, and indexes stored in flash not in system memory.