IXFR and nsd

[Colm MacCarthaigh]

On Fri, Mar 04, 2005 at 07:53:59PM +0100, Robert Martin-Legene wrote:
> I know it's not the easiest thing to do, since it's an external
> application, but with big zones with frequent updates (your RBL list
> being a candidate) won't you be spending most of your CPU time
> continuously compiling the new zone with zonec?

Yep, it takes us about 11 minutes to compile our zone, and that's on
some pretty beefy hardware with more than enough memory. But the one
updates every 3 hours, and it's currently taking more than that to
transfer - so it is at least an improvement.

> Would it be possible to copy the DB-file and do the IXFR-changes in that
> file directly, and then tell NSD to use the new file once done?

It won't really be that much quicker, it takes almost as much time to
read in the db file as it does to parse a zone-file, NSD it set-up for
run-time efficiency - not speedy compiles (but then nothing is, for the
type of sizes we're dealing with). I wrote an incremental compiler for
NSD a long time ago, which cached db files for each zone and only
recompiled the ones which had a newer timestamp than their db files and
then read all of the db files and output a master db file - but it
actually ended up taking longer to run than zonec itself, the vast
majority of time is just calls to read(), so it got abandoned.

-- 
Colm MacCárthaigh  /   HEAnet, Teach Brooklawn,  /   Innealtóir Líonra
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