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Re: DNS cpu utilization



We are currently hitting 45000-55000 queries every
five minute this is usually when cpu hovers around the
6-10 percent area.  This is usually from 8 am to 11:30
then it goes to around 1-3 percent in the late
afternoons.  I have all the services shutdown except
Bind and ssh is turned off as well.  I am not limiting
memory to bind. As far as swapping bind doesn't appear
to be swapping although I do have 2.5 meg being
swapped somewhere but I don't believe it is bind but
it's been there for awhile.  I may look into mrtg that
would be interesting to see what exacly the name
server is doing.


Peace
--- debian <debian@junkyjunk.com> wrote:
> I would suggest you setup some sort of monitoring on
> the bind process. I 
> personally use mrtg to graph the output of "rndc
> stats". The main dns 
> server I am responsible for runs about 12k-15k dns
> queries per 5 minutes 
> and has just about zero load. It's running on a
> slowish (aren't they 
> all) sparc.
> 
> I think your bind process is probably not configured
> optimally for your 
> machine. You might want to increase the amount of
> ram available to the 
> bind process (max-cache-size 50M;) and setup some
> server-side monitoring 
> so you can see what the machine is actually doing.
> 
> Is the machine hitting the swap at all? You DON'T
> want a dns server 
> swapping out to the disk all the time.
> Is the machine running any other services? You said
> dns was this 
> machine's primary service, but what else is running?
> Close down all of 
> the services except ssh and bind and see how it
> runs.
> 
> If you "push a machine too hard" you should not have
> ANY stability 
> problems. If you have stability problems anytime,
> you have faulty 
> hardware. If you start running the limit of your
> hardware, the machine 
> will let you know by dropping dns requests and being
> overall unresponsive.
> 
> -jason
> 
> 
> 
> peace bwitchu wrote:
> 
> >These two bind servers are authoritative for 200
> zones
> >and as far as clients go that's a hard one. 
> Because
> >of the way everything snowballed before I got ahold
> of
> >it it could be as many as > 10,000 this is a best
> >guess of course.  Once I prove that debian is the
> way
> >to go with this I plan to implement the split dns
> >topology.  I don't have any statistics yet but plan
> to
> >have some by week end.
> >
> >
> >Peace
> >--- Russell Coker <russell@coker.com.au> wrote:
> >  
> >
> >>On Thu, 8 May 2003 03:08, peace bwitchu wrote:
> >>    
> >>
> >>>this box working too hard or is the normal. 
> Since
> >>>this box is dedicated solely to dns I just want
> to
> >>>make sure that I'm not pushing bind too hard and
> >>>      
> >>>
> >>end
> >>    
> >>
> >>>up with stability problems.
> >>>      
> >>>
> >>Without knowing how many machines are using "this
> >>box" as a DNS proxy or how 
> >>important the domain(s) it serves are how can we
> >>determine if it's normal 
> >>load?
> >>
> >>Some DNS servers I've run have used 1% CPU time on
> a
> >>Pentium-166, some have 
> >>used >50% on a P3-1200.
> >>
> >>-- 
> >>http://www.coker.com.au/selinux/   My NSA Security
> >>Enhanced Linux packages
> >>http://www.coker.com.au/bonnie++/  Bonnie++ hard
> >>drive benchmark
> >>http://www.coker.com.au/postal/    Postal SMTP/POP
> >>benchmark
> >>http://www.coker.com.au/~russell/  My home page
> >>
> >>    
> >>
> >
> >
> >__________________________________
> >Do you Yahoo!?
> >The New Yahoo! Search - Faster. Easier. Bingo.
> >http://search.yahoo.com
> >
> >
> >  
> >
> 
> 


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