Re: [PATCH] minor optimization for EXT3

[Andi Kleen]

On Thu, Jul 10, 2003 at 04:51:30PM +0000, Alex Tomas wrote:
>  AK> Also dtimes in free inodes  can be now lost, can't they? Did you check 
>  AK> if that causes problems in fsck?  [my understanding was that ext2/3 fsck relies on the 
>  AK> dtime to make some heuristics when recovering files work better]
> 
> freed inodes will be lost. I've checked filesystem by fsck after lots of creations/removals.
> it seems OK.

iirc the dtime is used so that fsck can relink all non deleted inodes to lost+found
when a directory is corrupted. Without dtime there is no way to distingush
deleted and non deleted files, and just relinking everything would be quite
nasty.

With your patch this heuristic would lose some files.

That's more important for ext2 than ext3 of course, but even on ext3 
you could get a corrupted directory when you're unlucky (e.g. io error or similar)

-Andi