A utility is included in the distribution that will erase all the data stored in the JFFS and reset its configuration. This may be useful if the filesystem becomes corrupted and needs to be reset. The program is ‘mkjffs’ and can be found in the ‘/sbin’ directory. In order to use this program, first unmount the JFFS and run ‘mkjffs’.
umount /usr
/sbin/mkjffs /dev/flash0
A brief note about flash memory life expectancy: Typically a single sector in a flash memory chip can survive over 100,000 erase/write cycles. This means that for data logging or application updates the flash chip should not fail for a long time. Assuming 50 erase/write cycles per day, the flash should survive for about five and a half years. But this also means that the JFFS is not suited to handle any data intensive applications.
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