DNS performance?

[K.Guedider]

Hi everybody,

I have really urgent qustion regarding 'named' (BIND) performance. I read from DNS and BIND that, it is not advisable to have 10% of CPU used by the 'named' process. Do you have experienced 'named' using more than 10% of CPU. And what advices can you give me to improve 'named' performance (e.g. using the option cleaning-interval set to '0', option minimal-response set to 'yes',...)

Many thanks, any answer are very welcome. so please help!

[Arunvijai_4]

There are some tuning options available with Bind, you can see the details here,

http://docs.hp.com/en/B2355-90775/ch01s01.html
http://docs.hp.com/en/B2355-90775/ch01s01.html#beacgaci

-Arun

[Muthukumar_5]

which version you are using.? what is the configuration of named.conf? Machine configuration?

Post relavent informations.

-Muthu

[K.Guedider]

Thanks for the updates everyone!
[Muthu] I'm running BIND 8.2.7 is it helps. I'll further investigate through Internet to get more information.

Regards,

[Bill Hassell]

DNS is a service that is driven by requests from other boxes so the load is controlled by other computers. You can tune BIND somewhat but a runaway process on some box can easily saturate a DNS server with useless requests. If you see a high load (ie, 50% or more), then trace a few seconds of the named requests to see what machine clobbering your server.

[K.Guedider]

Many thanks folks!
I've got pretty obvious question. how bad it is to implement the option sortlist? I guess option are not really good since it diminishes named performance. Can anyone please confirm it and is there anyone who can assess the fall in performance it would bring about?

Many thanks,

[Geoff Wild]

I use an utility called dnstop - you can compile it on your dns server.

http://dns.measurement-factory.com/tools/dnstop/

I've compiled it on 11.11 machine.

Rgds...Geoff

[rick jones]

I'd say that 10% thing would only apply to a "non-dedicated" DNS server. And it is probably only a heuristic. There could be perfectly valid situations where named consumes say 40% of a CPU. There could also be perfectly invalid situations where it consumes other percentages.

In my on-again-off-again forays into named performance I stumbled across the "minimum responses" option of some versions of named. It should be in one of the dns/named related briefs at:

ftp://ftp.cup.hp.com/dist/networking/briefs/