Dreadful gmirror performance, though each half works fine

[Zaphod Beeblebrox]

On Tue, Apr 22, 2008 at 2:02 AM, Andrew Snow <andrew at modulus.org> wrote:

> Pete French wrote:
>
> > I did some benchmarking, and "load" gives me a bit better performance
> > than
> > "round-robin" so I've elected to use that. Haven't tried "prefer" as
> > syncing all the drives backwards and forwards to get the preferences set
> > seems a bit too much like hard work!
> >
>
> 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.