nginx жрёт память..

[valiy volodin <valiy-td@xxxxxxx>]

конфигурация
worker_processes  2;

error_log  /var/log/httpd/nginx/nginx-error.log;

pid        /var/run/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] $request '
                      '"$status" $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    sendfile        on;

    keepalive_timeout  2;
    output_buffers   64 32k;
    access_log /dev/null main;

    gzip  off;

    server {
        listen       80 default accept_filter=dataready accept_filter=httpready;
        server_name  host.ru www.host.ru;

        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host      $Host;
        ssi on;
        ssi_types text/htm;
        proxy_buffers 64 32k;


        location /pic/ {
                 proxy_pass http://192.168.16.1/pic/;
                expires 1d;
        }


        location ^~ /mod/ {
                proxy_pass  http://192.168.16.2:8888;
                access_log /tmp/log.log main;
        }

        location ~* ^.+\.(jpg|jpeg|gif|png|bmp|ico)$ {
                proxy_pass http://192.168.16.1;
          access_log  off;
           expires     1d;
        }


        location ~* '/[a-z]+/[0-9]+/comments' {
                proxy_pass http://192.168.16.1:8888;
        }

      location ~* '/[a-z]+/[0-9]+' {
                if ( $args ~* "action=vote" ) {
                        proxy_pass http://192.168.16.1:8888;
                        access_log /tmp/vote;
                }
                proxy_pass  http://192.168.16.2:8888;
        }

        location / {
               proxy_pass http://192.168.16.1:8888;
        }

        location /_css/ {
                root        /home/host.ru/.static/;
         }

        location /_js/ {
                root        /home/host.ru/.static/;
         }

        location /img/ {
                root        /home/host.ru/.statis/;
                expires 1d;
         }

        location ~* ^/(export|content|MSOffice|_vti_bin) {
        empty_gif;
        }

        error_page   500 502 503 504  /50x.html;
     
         }

за nginx-ом стоит апач с mod_accel , в определённые моменты nginx начинает 
дёргать с апача /50x.html , при этом сам nginx начинает жрать память в 
немереных количествах..
  PID USERNAME   PRI NICE   SIZE    RES STATE  C   TIME   WCPU    CPU COMMAND
51833 www         99    0   977M   786M RUN    0  59:21 32.18% 32.18% nginx
51834 www         98    0 19156K 18320K RUN    0  59:02 11.82% 11.82% nginx

под что он может съедать столько памяти?...