Bind-9.6 and Heavy Cpu Load

[Fajar A. Nugraha]

On Sat, Sep 26, 2009 at 5:43 PM, Bind <bind at dci.ir> wrote:
> Hello
> I have SunFire V880 (2 cpu +4G Ram) and installed bind 9.6.1-P1 on solaris
> 10.
> but my cpu load is very high!(above 90% during the pick time)
> bash-3.00# prstat -a
>    PID USERNAME  SIZE   RSS STATE  PRI NICE      TIME  CPU PROCESS/NLWP
>
>    562 root     2517M 2498M cpu0     0    0 1503:30:2  95% named/5
>   2394 root     3808K 3168K cpu2    59    0   0:00:00 0.9% prstat/1
>
> here are some relatde information:
> rndc status
> recursive clients: 841/9900/10000
> My input traffic which shown by MRTG is about "2.5" Mbps recieved
> requests(udp 53) and is normal in our network behavior during the pick time.
> my question is:
> does this high cpu load relate to input requests and is normall or it relate
> to something else?

Can you get the number of request per sec? I think you can get that
from output of two "rndc stats". On modern hardware it should be able
to handle several thousands reqs per sec easily.

Also, does named only use cpu0? It should be able to use all available
cpus. If not, you should be able to force it using "-n".

For comparison purposes, you might want to try using x86 server for
DNS server and see the results. From my experience it's a lot cheaper
and more powerful (compared to sparc or ppc) when used with bind. YMMV
though.

-- 
Fajar