LVM negates benefits of jounaling filesystems? [was RFE: autofsck]

[Alan Cox]

On Tue, Jun 10, 2008 at 09:49:16AM -0500, Eric Sandeen wrote:
>         if (unlikely(bio_barrier(bio))) {
>                 bio_endio(bio, -EOPNOTSUPP);
>                 return 0;
>         }
> 
> ... and somebody should probably measure the lvm overhead in general, I
> suppose.  :)

About 30% for disk performance on my test box. Obviously that isn't all
some LVM code corner case and there are other problems in there to reach
that difference on dbench. That's FC8 and I believe some lvm fixes for
performance have occurred since I did the runs (FC8 no updates).

Alan