There is disclosed a technique for use in managing multi-granularity flash translation layers in solid state drives. An SSD comprising a flash translation layer (FTL) table and flash memory space is provided. The FTL table is reconfigured into a plurality of multiple sub-tables, where a first sub-table has a first logical page size and a second sub-table has a second logical page size, the first logical page size being smaller than the second logical page size. The flash memory space is reconfigured into multiple flash memory sub-spaces. The first sub-table is mapped to the first flash memory sub-space the second sub-table is mapped to the second flash memory sub-space.