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This example shows how to estimate the lifetime of a raw NAND flash memory used in an embedded Linux system making use of the UBIFS file system. Specifically , the memory p/n is W29N08GVSIAA by TBDWinbond, which is a 1-bit ECC Single-Level Cell (SLC) component. In this case, the wear leveling algorithm is implemented at the Linux kernel level. This

According to the datasheet, the number of P/E cycles is 100000. The capacity is 1 GByte (8 Gbit). For the sake of simplicity, it is assumed that the file system makes use of the entire memory. Otherwise, only the capacity of the partition of interest has to be taken into account. Regarding the WAF, it is assumed it is 25. This means that for each byte written by the user-space applications and daemons, two five bytes are actually saved onto the memory.

TBW = ( 1 GByte * 100000) / 2 5 = 20000 GByte ~ 19.5 TByte

Assuming that the user-space software writes TBD 650 gigabytes every year, the expected lifetime is

LT = 20000 / 650 = 30.8 years

As stated previously, the system integrator can adopt an experimental approach as well. The following procedure describes how to determine the actual written data in for the system used for in this example.