memory consumption limit?

[Pavel Urban]

Hello,

we're running Bind 9.3.1 on RedHat Linux version 3, ES. After several 
days we end up with all memory consumed and DNS nearly unresponsive. We 
have one master and two slaves; this is a part of our configuration from 
one slave:

options {
         directory "/var/named";
         /*
          * If there is a firewall between you and nameservers you want
          * to talk to, you might need to uncomment the query-source
          * directive below.  Previous versions of BIND always asked
          * questions using port 53, but BIND 8.1 uses an unprivileged
          * port by default.
          */
         #query-source address * port 53;
         allow-transfer { 194.228.2.61/32; 193.85.7.100/32; 
193.85.1.12/32; 194.228.1.194/32; 194.228.2/24; };
         allow-recursion { 127.0.0.1; 194.228/16; 192.168/16; 172.16/12; 
10/8; 80.188/16; 83.208/16; 85.70/15; };
         notify yes;
         recursion yes;
         max-transfer-time-in 8;
         transfer-format one-answer;
         transfers-in 80;
         transfers-out 80;
         transfers-per-ns 40;
         coresize default;
         max-cache-size 200M;
         files 1024;
         stacksize default;
         cleaning-interval 30;
         interface-interval 0;
         recursive-clients 50000;
};


This is 'top' output from the same machine:

46 processes: 44 sleeping, 2 running, 0 zombie, 0 stopped
CPU states:  cpu    user    nice  system    irq  softirq  iowait    idle
            total   58.2%    0.0%    1.9%   0.5%     1.5%    5.9%   31.5%
Mem:   511736k av,  505212k used,    6524k free,       0k shrd,    2988k 
buff
                     385208k actv,   72524k in_d,    9404k in_c
Swap: 1052248k av,  486172k used,  566076k free                    8668k 
cached

   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND
22312 named     25   0  473M 435M  1136 R    59.6 87.2  3610m   0 named
22314 named     15   0  473M 435M  1136 S     0.3 87.2 209:11   0 named


Can you give me a tip what to tweak, or a link to the proper article/web 
page? Thanks!

-- 
***********************************************************************
Pavel Urban (pavel.urban at ct.cz)
IOL system disaster
Internet OnLine, www.iol.cz (owned by Czech Telecom, www.ct.cz)
***********************************************************************
    Vegetables should not operate electronic equipment.
           Computer Stupidities, http://rinkworks.com/stupid/
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