Hi folks, we have a very special problem with our proxy environment. It concerns only ONE uri http://www.mediaassetbox.com/client/escada. Other uris are working properly. Unfortunately this is a very bad uri because it works only with flash. Nevertheless our customer is working with it and we have a performance issue. If page starts to load it need approx. 60-70 seconds until the blue progress bar under the login field disappears. If I use another proxy product - eg. IWSS - the page loads in about 30 seconds. Also with direct internet connection we have this value ... So far so good - strange behaviour starts after working on the problem. Starting strace on the squid process - the performance increases to direct internet connection speed. Next we started debugging in squid itself - ALL,3 - without strace - the performance increases again. Starting with debug section 0 we found out that 'debug_options 5,3' (or 5,5 ...) increases the performance as fast as a direct connection. What we already did without success - disable ipv6 in os - strip configuration to minimum - using a cache_peer parent configuration (the IWSS proxy) - tried to find out, which systemcalls 'increases' the squid (see statistics below) Now some details about the system: - OS - Debian Squeeze - Linux xxx 2.6.32-5-amd64 #1 SMP Thu Nov 3 03:41:26 UTC 2011 x86_64 GNU/Linux - Squid - 3.1.6-1.2+squeeze2 Squid Cache: Version 3.1.6 configure options: '--build=x86_64-linux-gnu' '--prefix=/usr' '--includedir=${prefix}/include' '--mandir=${prefix}/share/man' '--infodir=${prefix}/share/info' '--sysconfdir=/etc' '--localstatedir=/var' '--libexecdir=${prefix}/lib/squid3' '--disable-maintainer-mode' '--disable-dependency-tracking' '--disable-silent-rules' '--srcdir=.' '--datadir=/usr/share/squid3' '--sysconfdir=/etc/squid3' '--mandir=/usr/share/man' '--with-cppunit-basedir=/usr' '--enable-inline' '--enable-async-io=8' '--enable-storeio=ufs,aufs,diskd' '--enable-removal-policies=lru,heap' '--enable-delay-pools' '--enable-cache-digests' '--enable-underscores' '--enable-icap-client' '--enable-follow-x-forwarded-for' '--enable-auth=basic,digest,ntlm,negotiate' '--enable-basic-auth-helpers=LDAP,MSNT,NCSA,PAM,SASL,SMB,YP,DB,POP3,getpwnam,squid_radius_auth,multi-domain-NTLM' '--enable-ntlm-auth-helpers=smb_lm,' '--enable-digest-auth-helpers=ldap,password' '--enable-negotiate-auth-helpers=squid_kerb_auth' '--enable-external-acl-helpers=ip_user,ldap_group,session,unix_group,wbinfo_group' '--enable-arp-acl' '--enable-esi' '--disable-translation' '--with-logdir=/var/log/squid3' '--with-pidfile=/var/run/squid3.pid' '--with-filedescriptors=65536' '--with-large-files' '--with-default-user=proxy' '--enable-linux-netfilter' 'build_alias=x86_64-linux-gnu' 'CFLAGS=-g -O2 -g -Wall -O2' 'LDFLAGS=' 'CPPFLAGS=' 'CXXFLAGS=-g -O2 -g -Wall -O2' --with-squid=/tmp/buildd/squid3-3.1.6 We can also provide HTTPFox (Firefox extension) lines for fast and slow connections. We searched the mailing list and found http://www.mail-archive.com/squid-users@xxxxxxxxxxxxxxx/msg33267.html - but there was no really helpful information. Other entries doesn't match. We collected the strace statistics only for this session: % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 97.66 0.004015 1 3209 epoll_wait 1.24 0.000051 0 145 145 connect 0.71 0.000029 0 870 recvmsg 0.22 0.000009 0 912 epoll_ctl 0.17 0.000007 0 299 getsockname 0.00 0.000000 0 484 2 read 0.00 0.000000 0 494 write 0.00 0.000000 0 444 close 0.00 0.000000 0 435 socket 0.00 0.000000 0 16 7 accept 0.00 0.000000 0 290 sendto 0.00 0.000000 0 290 bind 0.00 0.000000 0 290 setsockopt 0.00 0.000000 0 145 getsockopt 0.00 0.000000 0 616 fcntl 0.00 0.000000 0 1 getrusage ------ ----------- ----------- --------- --------- ---------------- 100.00 0.004111 8940 154 total Our squid config: *********** pid_filename /var/run/squid3-special.pid http_port 8081 hierarchy_stoplist cgi-bin ? acl QUERY urlpath_regex cgi-bin \? no_cache deny QUERY 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 127.0.0.1/32 acl to_localhost dst 127.0.0.0/8 acl SSL_ports port 443 acl SSL_ports port 8443 acl SSL_ports port 4643 acl Safe_ports port 80 acl Safe_ports port 443 acl Safe_ports port 21 acl Safe_ports port 11371 # PGP Keyserver acl Safe_ports port 8080 acl Safe_ports port 8443 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 CONNECT !SSL_ports http_access deny !CONNECT !Safe_ports http_access allow all icp_access deny all #debug_options 5,5 *********** network layout is: client -> firewall -> proxy -> firewall -> internet Does anyone has an idea what could be the cause for this strange behaviour? -- Andreas Schulz
