[Pdns-users] PowerDNS Recursor Performance and Tuning

[Otto Moerbeek]

On Sun, Jan 16, 2022 at 01:11:55PM +0330, Hamed Haghshenas wrote:

> Hello,
> Thanks for your help. I changed them .
> 
> > If you have 8G of RAM, likely the default cache sizes could be enlarged
> (max-cache-entries for the record cache and max-packetcache-entries for the
> packet cache)
> 
> how calculate the best number for "max-packetcache-entries" and
> "max-cache-entries"

This is very mch dependent on usage. Study memory usage and cache
hit ratios.

> 
> >Virtulization *could* be an issue, for example when the network interface
> is virtualized in a way thet hinders performance. 
> 
> I can't change my Platform for now !!!
> 
> >If you are using NAT: this *kills* the performance. See
> https://docs.powerdns.com/recursor/performance.html
> 
> I move it to my Edge Network and set Public IP .
> 
> >Depending on kernel version and other factors resuseports and multiple
> distributor thread might work better or not, best to start with
> reuserport=no and distributor-threads=1, test & measure and then change to
> yes and 4 and compare performance on your actual setup.
> 
> My Kernel is 3.10.0-862.el7.x86_64, i set reuserport=no and
> "distributor-threads=1", "threads=3"
> 
> >If you see a lot ot bogus results this might impact performance
> 
> "dnssec-log-bogus=yes" removed.
> 
> > entropy-source=/dev/random
> 
> changed to default
> 
> > lowercase-outgoing=yes
> 
> I ignore it.
> 
> > quiet=no
> 
> I need the logs and should export domains to my analyzer platform .

There are much better ways to do that, see
https://powerdns.com/recursor/lua-config/protobuf.html for logging via
protobufs. Again, text logging of all queries is not a good idea.

	-Otto