Dreadful gmirror performance, though each half works fine

[Andrew Snow]

Zaphod Beeblebrox wrote:
>     I use this patch for sbin/geom/class/mirror/geom_mirror.c
> 
>     Change:
>      md.md_priority = i - 1;
>     To:
>      md.md_priority = i - 1 + 100;
> 
> 
> I hate to ask for the "right"  solution, but shouldn't we be patching 
> the gmirror userland to accept a priority argument to label and make the 
> kernel part listen to that?  This patch does make sense --- but it 
> doesn't go far enough.
> 
> Also, it seems sensible that you should be able to modify the priority 
> values of a running disk.

Both of those are good ideas.  But for years, no one can be bothered 
making a patch.  At least my patch is only one line, and solves 90% of 
the problem, and still no one can be bothered committing it.

Maybe we should apply my patch for now, until someone works on the rest.

- Andrew