[squid-users] Mixed environment performance

Hello fellow squid wranglers,

I'm running squid on a network with about 10 linux stations (with 15+
simultaneous users per station), and about 20 windows stations (with
only one user per station). Top download speed is the same for both
linux and windows boxes, but overall browsing is significantly slower on
the windows boxes. At first I thought the problem was with the windows
boxes not receiving the dns information quickly, but tests have shown
otherwise. There is a delay of one to two seconds for each connection to
squid. For instance, a page with several images would take 4 seconds to
fully render, first two seconds to load the page, then two seconds as it
concurrently downloads each image. If the user were to go to that page
again I can watch the squid logs and see a TCP_HIT for each image and
the web page, but the render time remains the same. If I allow the
machine to directly connect to the internet (using the same dns servers)
there is no such delay when rendering pages.

Each windows box allowed through the proxy is listed in acl/pc_hosts and
each linux box is listed in acl/unix_hosts with each user either in
acl/allow_user or acl/deny_user. The pertinant parts of my squid.conf
are such:

acl allow_user ident "/etc/squid/acl/allow_user"
acl deny_user ident "/etc/squid/acl/deny_user"
acl unix_hosts srcdomain "/etc/squid/acl/unix_hosts"
acl pc_hosts srcdomain "/etc/squid/acl/pc_hosts"
http_access allow allow_user !deny_user unix_hosts
http_access allow pc_hosts

Is there a performance penalty for having pc_hosts that don't
authenticate along side unix_hosts that do? Is squid trying to access a
non-existant ident server on the windows stations? Is there a better way
to define access for pc_hosts? Any help with this matter would be
greatly appreciated.

The full squid.conf follows:

http_port proxy:8080
hierarchy_stoplist cgi-bin ?
acl QUERY urlpath_regex cgi-bin \?
no_cache deny QUERY
auth_param basic children 5
auth_param basic realm Squid proxy-caching web server
auth_param basic credentialsttl 2 hours
auth_param basic casesensitive off
request_body_max_size 0
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern . 0 20% 4320
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 to_localhost dst 127.0.0.0/8
acl SSL_ports port 443 563
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 563 # https, snews
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT
acl porn url_regex "/etc/squid/acl/porn"
acl porn1 url_regex "/etc/squid/acl/porn1"
acl noporn url_regex "/etc/squid/acl/noporn"
acl allow_user ident "/etc/squid/acl/allow_user"
acl deny_user ident "/etc/squid/acl/deny_user"
acl allow_sites dstdomain "/etc/squid/acl/allow_sites"
acl unix_hosts srcdomain "/etc/squid/acl/unix_hosts"
acl pc_hosts srcdomain "/etc/squid/acl/pc_hosts"
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access allow allow_sites
http_access deny porn porn1 !noporn
http_access allow allow_user !deny_user unix_hosts
http_access allow pc_hosts
http_access deny all
http_reply_access allow all
icp_access deny all
cache_effective_user squid
cache_effective_group squid
coredump_dir /var/spool/squid
Received on Thu May 18 2006 - 16:24:58 MDT