Re: question: the performance of jffs2 on UBI

Artem B. Bityutskiy
2006-07-27T13:33:27Z

Artem B. Bityutskiy wrote:
> falls huang wrote:
>
>> The UBI and jffs2 both provide wear leveling. Will the repeated
>> wear-leveling reduce the performance of system ?
>
> I guess jffs2 ought to be slower on UBI, but little. My *very* rough
> test on mtdram device showed that JFFS2 over UBI is about 5% slower. But
> more accurate testing should be done.

And note: of course, JFFS2 was not designed for UBI, so it does not use
UBI advantages. But still, it makes a lot of sense to use JFFS2 over UBI
because in this case you have much freedom in partitioning your flash as
you like.

I'm planning to return to JFFS3 research/development some day and design
JFFS2 to work on top of UBI devices.

The alternative way to is to create a good block device layer over UBI,
and then use conventional file systems (N.B. the mtdblock driver is
*not* a good block device layer).