named and cpu

Suddenly the load raise and I don't know why. My spec is, celeron 2,4 and 512 Ram. Why is named eating so much memory ? I have about 50 domanin.

When I run top I see.

17:01:58 up 22 days, 20:59, 1 user, load average: 2.53, 1.63, 1.41
150 processes: 145 sleeping, 5 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 42.1% 0.0% 57.8% 0.0% 0.0% 0.0% 0.0%
Mem: 512704k av, 502332k used, 10372k free, 0k shrd, 45744k buff
263064k active, 197476k inactive
Swap: 1052216k av, 76992k used, 975224k free 268152k cached

PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME CPU COMMAND
23941 mysql 9 0 11304 11M 1440 S 40.8 2.2 9:15 0 mysqld
407 root 8 0 5044 4784 4664 S 29.8 0.9 17:45 0 httpd
24402 named 9 0 2928 2928 2072 S 24.9 0.5 12:12 0 named

 

 

 

 

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