Re: [RFC 1/2] ext3: enlarge blocksize and fix rec_len overflow

[Johann Lombardi <johann.lombardi@bull.net>]

Hi,

> >I have no objection to this at all, but I think it will lead to a slightly
> >more complex implementation.  We even discussed in the distant past to
> >make large directories a series of 4kB "chunks", for fs blocksize >= 4kB.
> >This has negative implications for large filenames because the internal
> >free space fragmentation is high, but has the advantage that it might
> >eventually still be usable if we can get blocksize > PAGE_SIZE.
> >
> >The difficulty is that when freeing dir entires you would have to be
> >concerned with a merging a dir_entry that is spanning the middle
> >of a 2^16 block.
> 
> That is easy, just don't let an entry span subblocks by not letting
> delete merge past the end of a subblock, just a minor tweak.  New block
> initialization needs an outer loop on subblocks and that's it, I think.

I've been working on a patch implementing this feature. It currently works w/o 
htree.
With dir_index, the difficulty is that an entry can span subblocks after a leaf
block split.

Cheers,

Johann