[Ubuntu-BR] Acesso lento pelo Squid

[Diego Walisson]

Senhores, tive que reintalar o Squid 2.6.STABLE18 + SquidGuard + Bind9 num
Ubuntu Server 8.04 recentemente e percebi que a partir daí os usuários
começaram a reclamar com certa frequência de lentidão no acesso a qualquer
site da internet, pois antes do procedimento era tudo uma maravilha.
A máquina é virtual num VMware Server, com proc. Core 2 Duo 1,86Ghz e 1,5 GB
de RAM. Funciona como servidor proxy e DNS.
Vejam minha configuração:

*dns_nameservers 172.x.x.x <------   Esse DNS aqui é outro servidor na rede.

http_port 2201
visible_hostname proxy-xxxxx

acl all src 0.0.0.0/0.0.0.0
acl manager proto cache_object
acl localhost src 127.0.0.1/255.255.255.255

acl SSL_ports port 443          # https
acl SSL_ports port 563          # snews
acl SSL_ports port 873          # rsync
acl Safe_ports port 80          # http
acl Safe_ports port 21          # ftp
acl Safe_ports port 443         # https
acl Safe_ports port 70          # gopher
acl Safe_ports port 210         # wais
acl Safe_ports port 631         # cups
acl Safe_ports port 873         # rsync
acl purge method PURGE
acl CONNECT method CONNECT

http_access allow manager localhost
http_access deny manager
http_access allow purge localhost
http_access deny purge
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports

acl liberados url_regex -i "/etc/squid/liberados"
http_access allow liberados

acl redelocal src 172.x.x.x/16
acl redelocal src 10.x.x.x/16
acl redelocal src 201.x.x.x/26

http_access allow localhost
http_access allow redelocal

http_access deny all

cache_mem 300 MB

maximum_object_size_in_memory 64 KB

cache_dir aufs /var/spool/squid 2048 16 256

minimum_object_size 2 KB

maximum_object_size 512 MB

cache_swap_low 90
cache_swap_high 95

access_log /var/log/squid/access.log squid

logfile_rotate 10

redirect_program /usr/bin/squidGuard
redirect_children 10

acl QUERY urlpath_regex cgi-bin \?
cache deny QUERY

refresh_pattern ^ftp:           15      20%     2280
refresh_pattern ^gopher:        15      0%      2280
refresh_pattern .               15      20%     2280

acl apache rep_header Server ^Apache
broken_vary_encoding allow apache

extension_methods REPORT MERGE MKACTIVITY CHECKOUT

#error_directory /usr/share/squid/errors/Portuguese

hosts_file /etc/hosts

coredump_dir /var/spool/squid*

Há algo de errado nesse squid.conf ou algo que pode ser otimizado para
acabar (ou amenizar) essa lentidão?

Desde já agradeço.

-- 
*Diego Walisson*
*diegowalisson em gmail.com
twitter.com/dwalisson
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