[Pdns-users] Performance of pdns authoritative server on big machines with different backends

[Kenneth Marshall]

On Tue, Jan 04, 2011 at 03:20:44PM +0100, Marc Haber wrote:
> Hi,
> 
> in my current project, I have the task of finding out which
> performance to expect from a PowerDNS authoritative server running on
> a big machine.
> 
> My test box is an HP DL 360 G6 with two quad core hyperthreading CPUs
> (so I have 8 real cores with Linux seeing 16 cores) and 48 GB RAM
> running Debian GNU/Linux unstable with kernel 2.6.36, and powerdns
> 2.9.22.x-3 statically compiled (I ported the packaging of the
> pdns-static.deb from powerdns.com to x-3).
> 
> My test setup is deliberately big and contains about ten million zones
> which are served via mysql backend (MySQL servr running on the same
> system, connected to via file system socket). The cache of the MySQL
> server has been warmed up, and the box has enough memory to hold the
> entire database in RAM (and it does so).
> 
> The simplest test setup is running
> dnsperf -s <address> -t 5 -q 5000 -l 600 -d queryfile
> with a query file containing roughly 4,2 million synthetically
> generated queries, a good part of them generating NXDOMAIN.
> 
> After some days of testing, I found out that this setup is fastest
> when I configure PowerDNS with 32 receiver threads and 48 distributor
> threads. While the test is running, PowerDNS roughly takes four cores,
> while MySQL takes eight to ten cores, with a good percentage of the
> system still being idle, putting out roughly 35 kqps.
> 
> I would expect the test to be able to saturate my CPUs and thus
> suspect that there is something wrong in my setup.
> 

Hi Marc,

Have you tried running multiple PDNS servers at once with possibly
multiple MySQL backends as needed to scale?

Cheers,
Ken