need arguments to use JFFS2

[Charles Manning]

It is virtually impossible to make any firm statements without understanding 
your needs a bit better.

A few others have already covered cramfs and JFFSx. I can tell you a bit 
about YAFFS.

YAFFS only works with NAND flash. YAFFS does not provide compression (like 
JFFS does). YAFFS is faster than JFFS2 in most situations and uses less RAM.
Mileage will vary though. Compression is not necessarily a huge advantage for 
JFFSx. Some people loop-mount a cramfs image stored on YAFFS to get the 
benefits of compression as well as the faster speed for other files.

If you have NAND, then most likely YAFFS will serve you better for larger 
flash arrays (say 16MB and bigger) and JFFS2 for smaller arrays.

YAFFS will do nothing for you if you only have NOR flash.

If you're designing a new board then consider including NAND flash for 
storage (rather than NOR). NAND is cheaper, smaller (physically), bigger (in 
bytes) and faster. You can then use YAFFS or JFFS2 (even both - by 
partitioning the device).


-- Charles