process shared robust mutexes for tdb

[Ira Cooper]

On Tue, Dec 25, 2012 at 3:42 PM, Jeremy Allison <jra at samba.org> wrote:

> On Mon, Dec 24, 2012 at 07:50:22PM -0500, Ira Cooper wrote:
> >
> > Well.. we do it already (locking the vnode, in fact what you are
> suggesting
> > is already implemented in the kernel in a sense)  For locking.tdb it'd be
> > nice to stop.  But locking.tdb isn't the evil one for me.  serverid.tdb
> is,
> > believe it or not.  (I've actually gone through with dtrace to figure
> that
> > out...)
> >
> > I have code in need of cleanup to basically remove all locking from the
> > common case from serverid.tdb.  (I have tested it, I am using it.  So it
> > isn't vapor, it just needs cleaning up so others can use it ;). )
> >
> > In fact using it I've removed fcntl from the "critical paths" in my
> > use-case, allowing us to scale with CPU power, and also go faster in
> > general.  I'll try to turn that code in early January.  I've already sent
> > out pre-review copies.  So, it is a matter of dealing with the comments
> > I've gotten, so I can get it ready to go in.  (At least for 3.6.  For
> > master/4.0 it may not be as needed.  For 3.6 users... it is quite nice.)
>
> I will remind you of this in the new year :-).
>
> Don't forget to finish it up ! :-) :-).
>

The code works... just not the way everyone in the world would want :P.

-Ira