On 26.04.2012 08:17, Fuhrmann, Marcel wrote:
Hello list,
I am a squid newbie, but i am working on it. So please forgive my
lack of knowledge.
Sometimes several flash videos don't load or it takes a long time for
starting the video.
I have read that dns resolution is often a problem for long loading
times. But
DNS works fine, the squid server isn't busy and the flash browser
plugin is up to date.
As far as i know squid has a really good debug log. But as long as i
don't know what i am searching for, it is not easy for me to
identify/solve this problem.
Maybe somebody can give me a hint?
I am using squid 3 from ubuntu 10.04 repositories, havp as parent
proxy and authentication via ADS.
It is a virtual machine on vSphere5. 2gb ram, raid 10 for
/var/spool/squid3.
RAID-10 will be slowing your disk I/O down proportionally to the number
of disks you are splicing with the RAID-0 features.
http://wiki.squid-cache.org/SquidFaq/RAID
This is an overall speed bump rather than specifics, although it may
show up worst when transferring larger objects due to their larger disk
I/O requirements.
Here is my squid.conf:
cache_mem 64 MB
maximum_object_size 1 KB
maximum_object_size_in_memory 128 KB
This is fine, but note that is means videos and large images all
operate via the disks and are I/O bound on both network and disk
capacity speeds.
cache_replacement_policy heap LFUDA
memory_replacement_policy heap GDSF
cache_dir aufs /var/spool/squid3 8000 256 256
dns_nameservers 10.4.1.20
cache_peer localhost parent 8899 0 no-query no-digest
The parent proxy could be the limit. Most traffic
url_rewrite_program /usr/bin/squidGuard -c /etc/squid/squidGuard.conf
url_rewrite_children 20
What is squidGuard doing? re-writers and redirectors can be a
bottleneck as Squid waits for them to process the request details.
cache_effective_user proxy
error_directory /usr/share/squid3/errors/de-de
auth_param ntlm program /usr/bin/ntlm_auth
--helper-protocol=squid-2.5-ntlmssp
auth_param ntlm children 20 startup=0 idle=1
auth_param basic program /usr/bin/ntlm_auth
--helper-protocol=squid-2.5-basic
auth_param basic children 5
auth_param basic realm Domain Proxy Server
auth_param basic credentialsttl 2 hours
auth_param basic casesensitive off
authenticate_cache_garbage_interval 10 seconds
authenticate_ttl 300 seconds
external_acl_type nt_group ttl=5 children=5 %LOGIN
/usr/lib/squid3/wbinfo_group.pl
acl INTERNET_SQUID external nt_group internet
NTLM and winbind limit your squid to 256 concurrent logins. You say the
proxy is not loaded, so this should not matter but its something to be
aware of. When that capacity is reached new login attempts will be
blocked waiting for the helpers to become free.
acl snmptest snmp_community public
acl manager proto cache_object
acl localhost src 127.0.0.1/32
acl to_localhost dst 127.0.0.0/8 0.0.0.0/32
acl SSL_ports port 443
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 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
snmp_port 3401
snmp_access allow snmptest localhost
snmp_access deny all
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access allow localhost
http_access allow INTERNET_SQUID
http_access deny all
icp_access deny all
htcp_access deny all
http_port 3128
hierarchy_stoplist cgi-bin ?
You can try dropping hierarchy_stoplist. It is preventing dynamic
website traffic with query parameters ("?...") going through your peer.
Which may or may not be related to speed differences between objects
with or without ? in the URL.
access_log /var/log/squid3/access.log squid
cache_log /var/log/squid3/cache.log squid
refresh_pattern ^ftp: 144020% 10080
refresh_pattern ^gopher:14400% 1440
refresh_pattern (cgi-bin|\?)0 0% 0
Old pattern. The better one is:
refresh_pattern -i (/cgi-bin/|\?)0 0% 0
refresh_pattern . 0 20% 4320
icp_port 0
There is nothing really standing out as a cause in this config.
Amos
