Hello. I am tring to optimize squid for best possible performance. it is in production and it's doing more than 350req/sec. At peaks upto 500req/sec. My problem is only one. 100% cpu. :-) I tried to update my debian to 2.6.16 and recompiled squid: Squid Cache: Version 2.5.STABLE12 configure options: --prefix=/usr --exec_prefix=/usr --bindir=/usr/sbin --sbindir=/usr/sbin --libexecdir=/usr/lib/squid --sysconfdir=/etc/squid --localstatedir=/var/spool/squid --datadir=/usr/share/squid --enable-async-io --with-pthreads --enable-storeio=ufs,aufs,diskd,null --enable-linux-netfilter --enable-arp-acl --enable-removal-policies=lru,heap --enable-snmp --enable-delay-pools --enable-htcp --enable-epoll --enable-cache-digests --enable-underscores --enable-referer-log --enable-useragent-log --enable-auth=basic,digest,ntlm --enable-carp --with-large-files i386-debian-linux the thing I realy don't like is 25% cpu + 50% system cpu . why the 50% system!!!!! can anyone help? Kind Regards Michal Mihalik