Bind 8.1.2 in.named memory leak in Solaris 7

[Joaquim Eudes Mendes Gomide]

Hi Jim

I´m having the  problem describe in the article. Look at top´s information
below:

load averages:  0.02,  0.01,  0.02                                     10:44:42

29 processes:  28 sleeping, 1 on cpu
CPU states: 99.4% idle,  0.0% user,  0.6% kernel,  0.0% iowait,  0.0% swap
Memory: 512M real, 8728K free, 564M swap in use, 71M swap free

  PID USERNAME THR PRI NICE  SIZE   RES STATE   TIME    CPU COMMAND
28729 root       1  58    0  545M  417M sleep  33:57  2.78% in.named
29065 root       1  58    0 2120K 1504K cpu     0:00  0.51% top
29043 root       1  48    0 1784K 1280K sleep   0:00  0.03% ksh

The server is just 3 day up and it is only a name server. This is a internal
dns server and is used for zone transfer, so the cache should not grow as big
as it is. We don´t have so many internal hosts to cache.

Any ideas?

Joaquim Gomide

Jim Reid wrote:

> >>>>> "Joaquim" == Joaquim Eudes Mendes Gomide <jgomide at bancobrasil.com.br>
> writes:
>
>     Joaquim> I got an article on Sunsolve that says: "The DNS process
>     Joaquim> ´in.named´ continually consumes memory until no
>     Joaquim> memory is available. At this point in.named terminates
>     Joaquim> leaving a possibly large core file."  Is this problem a
>     Joaquim> Bind 8.1.2 or a Solaris version of Bind bug? The same
>     Joaquim> article says that there is no work around, too.  Does the
>     Joaquim> Bind 8.2 solves this problem?
>
> The article is a little bit misleading. It gives the impression that
> name servers guzzle memory until the system runs out and then named
> crashes and dumps core. This isn't quite true. It is true that the
> name server will die if it cannot get more memory from the OS. However
> that should be a rare event. And if your system can't let the name
> server process have more memory, then you have to contend with more
> serious underlying problems. [Like a grossly overloaded computer or a
> woefully inadequate local DNS infrastructure.]
>
> The size of a name server process grows as it receives queries. These
> make named cache more and more data as it looks up names and sends
> queries to other name servers. However the size of the process tends
> to stabilise after the name server has been running for a few
> days. Old entries get expired from the cache and the lookup patterns
> from local resolvers tend to request the same names.
>
> This "problem" is the way name servers work. They take more memory
> from the OS as they need to cache resource records. In general this
> doesn't grow without limit. I believe that BIND9 will behave more
> gracefully when named's memory allocation requests fail. However this
> isn't due to be released until next year and it may be a year after
> that before vendors ship it with their OS releases.
>
> FWIW the name server on a Solaris box here has been running for a few
> weeks now and it only uses 1.5M of VM. This isn't a noticeable load on
> the system and is nowhere near the resource limits of the OS.

--
   /\//  Joaquim Eudes Mendes Gomide
  / /\   Analista de Informatica
  \/ /   Banco do Brasil S.A.   http://www.bancobrasil.com.br
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