BIND 9.3.0 issues regarding shutdown and memory usage

[Bernhard Schmidt]

Hello everyone,

excuse me if those questions have already been answered, I could not
find something by searching through the archive but I could as well have
used the wrong keywords.

I'm currently trying to use BIND 9.3.0 as an IPv6-enabled resolver for
our mail-setup. It has one big slaved zone (rbl-plus.mail-abuse.com,
size of the zonefile is about 110M), everything else is cached. It is
running on a Dual-Xeon (HT-enabled) on SLES9. I compiled it myself using
no specific options except --with-threads.

I have found two problems I could not really fix so far:

a) When I issue a 'rndc stop' BIND gives me the following output when
   started with "-g -d 2":

   24-Jan-2005 16:42:53.872 received control channel command 'null'
   24-Jan-2005 16:42:53.872 received control channel command 'stop'
   24-Jan-2005 16:42:53.872 shutting down: flushing changes
   24-Jan-2005 16:42:53.872 stopping command channel on 127.0.0.1#953
   24-Jan-2005 16:42:53.873 no longer listening on 10.156.6.10#53
   24-Jan-2005 16:42:53.873 calling free_rbtdb(.)
   24-Jan-2005 16:42:53.873 done free_rbtdb(.)
   24-Jan-2005 16:42:53.875 calling free_rbtdb(.)
   24-Jan-2005 16:42:53.875 done free_rbtdb(.)
   24-Jan-2005 16:42:53.879 calling free_rbtdb(rbl-plus.mail-abuse.org)
   24-Jan-2005 16:42:53.880 calling free_rbtdb(.)
   24-Jan-2005 16:42:53.880 done free_rbtdb(.)
   24-Jan-2005 16:42:53.880 calling free_rbtdb(.)
   24-Jan-2005 16:42:53.882 done free_rbtdb(.)

   Here BIND sits eating 100% of one of the four logical CPUs and does
   nothing for at least 15 minutes (maybe longer, I killed it after that
   period). It doesn't listen to rndc anymore (of course) and does nothing
   I can see. SIGHUP, SIGTERM or any other signal except SIGKILL doesn't
   help a bit).

   This behaviour is consistent whether I used threading or not. No
   difference here.

b) Something I couldn't reproduce so far, but perhaps someone has an
   idea what could cause something like this. During the weekend (two days
   up) the threaded binary went for 1.5G used memory. After restart all
   versions are at about 500M, after one day hard testing maybe 700M.

 1.) In this state (1.5G used) I could not get it to use a single byte
     more memory even when running some 100k random queries through it.
     I read somewhere that this is the process limit of x86 Linux, any
     idea how to increase that? The box has 4G RAM and is dedicated for
     that service, so I'd like to use it

     Kernel 2.6.5-7.111.19-bigsmp #1 SMP (SLES9 distribution kernel)

 2.) Memory consumption seems to be way too high, the box is currently
     during test doing about 5 qps, even when manually running 400k
     queries dumped on another resolver I can't get it past 700M. But at
     this particular runtime it had 1.5G and stayed there.

I would be glad about any tips you have to offer

Bernhard