NAND out of space crash

[David Woodhouse]

On Mon, 2008-07-21 at 09:51 -0700, Deepak Saxena wrote:
> On Jul 21 2008, at 13:39, C. Scott Ananian was caught saying:
> > > 2) JFFS2's behavior when the file system is almost full.  When it gets
> > > almost full, it can spend all its time trying to garbage collect, and
> > > you can lose completely (the system sort of gets the "slows", and grinds
> > > to a halt).
> > >
> > > As to 2), there are patches done by Nokia (deployed on the N800 and
> > > similar devices) that reserve some extra space and report out of space
> > > before the system "gets the slows".  These are in Dave's incoming queue
> > > to merge into JFFS2 the last I heard.  I don't know if he's merged them.
> > 
> > These are less critical, IMO.  I have filled up NAND, and "the slows"
> > are not debilitating.  The issues above are. We should encourage Dave
> > to fix this issue and the other known JFFS2 bugs (trac #6480, for
> > instance)  -- or get dsaxena to do so -- for 9.1.
> 
> #6480 is fixed as of yesterday, should be in next joyride.

Yeah. Since it was purely cosmetic I figured it might as well just wait
to come through 'naturally'.

> I'll be re-doing Nokia's patches so that they go upstream if we still want
> them after 8.2 is out; however, I don't think the approach used by them actually 
> helps us.  We already have a very limited amount of storage space and reserving 
> space for the root user just reduces what the end user can actually use.
> 
> I think analyzing performance of non-JFFS2 file systems and picking
> a replacement should be a high-priority item for 9.1 update.

I'm looking at making btrfs work on pure flash. It looks fairly sane in
that respect. Using a 'standard' file system will have benefits...


-- 
dwmw2