jffs2: too few erase blocks

[Duke]

On 10/25/07, Jamie Lokier <jamie at shareable.org> wrote:
> Josh Boyer wrote:
> > > Hi All,
> > > What's the deal with "too few erase blocks" message?
> > > Is one block too few for a jffs2 partition?
> > > My block size if 256K and I created a small jffs2 256K partition for
> > > read/writing.
> > > Is this really too small for jffs2? If so, is there anything I can do for this?
> >
> > Yes, it's too small.  JFFS2 requires a certain percentage of blocks in
> > the partition to be reserved for it's usage.  At one point, it was 5
> > eraseblocks.
>
> Fwiw, 5 blocks worth of free space is no guarantee that it'll be fine.
> I have a 1MB JFFS2 partition with 64kB eraseblocks.  That's 320kB in 5
> blocks.  But it can return disk full errors when reporting more than
> 320kB free with 'df' (somewhere between 5 and 6 blocks worth), and it
> can also do strange things shortly before it returns disk full errors,
> like spending lots of CPU on GC.

Is there another read/write filesystem I can use in this space?

If I were to create a subdirectory and rw to that dir only? and can I
do this with mtd_debug tool?