[PATCH] speed up tdbbackup

[Volker Lendecke]

On Thu, Jul 23, 2015 at 09:09:42AM -0700, Jeremy Allison wrote:
> On Wed, Jul 22, 2015 at 12:07:55PM +0200, Volker Lendecke wrote:
> > Hi!
> > 
> > Attached find patches that speed up tdb measurably. I don't
> > get really reliable results with "time", but I've seen up to
> > 25% improvement on a 10-million small record tdb file on
> > /dev/shm/. If I run a 1-million record tdbbackup, callgrind
> > goes down from 6,916,115,142 to 4,888,697,132 instructions
> > run. This pretty repeatable.
> > 
> > Now guess what patch has the larger effect... It's the
> > tdb_oob one. I can only guess why this is the case. Probably
> > pointer chasing is really expensive and the CPU caches are
> > better utilized if we can call a common function.
> > 
> > Review&push appreciated!
> 
> Just fyi - looks good to me but I got an autobuild
> fail on push, so I'll take a closer look !

Just to make sure: It did survive a private autobuild for me.

Volker

-- 
SerNet GmbH, Bahnhofsallee 1b, 37081 Göttingen
phone: +49-551-370000-0, fax: +49-551-370000-9
AG Göttingen, HRB 2816, GF: Dr. Johannes Loxen
http://www.sernet.de, mailto:kontakt at sernet.de