md (file backed) performance [Was: Re: unionfs 5.4]

Am Donnerstag, 17. März 2005 02:24 schrieb Jeff Roberson:
> On Thu, 17 Mar 2005, Emanuel Strobl wrote:
> > Am Mittwoch, 16. März 2005 07:16 schrieb Sergey Matveychuk:
> > > Jeff Roberson wrote:
> > > >>just ffs: 1:47 min
> > > >>nullfs:   1:43 min (oops!:)
> > > >>nullfs in jail: 12:12 min
> > > >>
> > > >>Almost ten times degradation.
> > > >
> > > > Can you try this again on current?  I just committed some changes to
> > > > nullfs which vastly simplify the locking.  I don't see anything
> > > > inherent in the code that should cause such a slowdown.
> > >
> > > The problem has gone. Thanks Jeff!
> > > Don't forget MFC it some time :)
> >
> > Highly appreciated for 5.4!!!
>
> I can't MFC this for 5.4, it requires too much of the new vfs architecture
> to properly function.  I'll mail re_at_ to see what their opinion is for 5.5.

Oic. I haven't tracked -current since christmas so I'd like to ask if you know 
anything new about file backed md performance.
I wanted to use that for jail systems but performance was really bad.
Does your great work also improve md behaviour?

Thank you very much,

-Harry