Limitations of Linear Flash Memory for Block Devices

Although linear flash memory technology is very commonly used to implement block devices, there are some limitations to the hardware:

• Linear flash memory typically provides read-access times similar to ordinary DRAM but has slow write-access times and limited write-cycle lifetimes. Linear flash memory is therefore unsuitable as a replacement for true DRAM. Instead, linear flash memory is best suited for supplementary storage space, as a solid-state replacement for disk drives.
• On Windows CE, new memory technology drivers (MTDs) cannot be added dynamically to support additional types of linear flash memory hardware. Only OEMs can add support for new types of linear flash memory hardware.
• Windows CE does not inherently support resident flash arrays (RFAs) because there is no standard approach for handling tasks such as error correction, interleaving, and wear leveling. OEMs can add linear flash memory hardware directly to platforms, but they should investigate the feasibility of using a socketed form of linear flash memory, such as DiskOnChip.
• The TrueFFS driver must be a stream interface driver.