Improving JFFS2 Mount Times under Linux - KBA218977

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Question:

How can I speed up JFFS2 mount times? 

 

Answer:

The Linux JFFS2 flash file system was integrated into the Linux kernel in 2001 (see https://en.wikipedia.org/wiki/JFFS2). With today’s large densities, some of its algorithms show an increased runtime behavior. For example, when the file system is mounted, JFFS2 scans the entire flash for data nodes to build a lookup table in RAM. This can consume a lot of time for large densities. The long mount times are the result of an extensive scan without summary nodes. To speed up the parsing process, an optional summary feature is provided where small nodes are written at the end of every sector. At probing time, only these summary nodes must be parsed and the mount time reduces significantly. To enable this feature, just enable CONFIG_JFFS2_SUMMARY in the Linux kernel configuration.