nf_conntrack: table full, dropping packet.

Does anyone know how to get rid of/turn off/kill/remove/exorcise netfilter and/or conntrack?
I don't use iptables and it seems to cause a lot of overhead.

Does it require a custom compiled kernel? I am using CentOS and Fedora standard precompiled kernels right now.

Thank you for any help in this frustrating matter.

# lsmod | grep -i ip

ipv6                  290320  20

sysctl -a | grep -i netfilter

net.netfilter.nf_conntrack_generic_timeout = 12
net.netfilter.nf_conntrack_tcp_timeout_syn_sent = 12
net.netfilter.nf_conntrack_tcp_timeout_syn_recv = 12
net.netfilter.nf_conntrack_tcp_timeout_established = 2000
net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 12
net.netfilter.nf_conntrack_tcp_timeout_close_wait = 12
net.netfilter.nf_conntrack_tcp_timeout_last_ack = 12
net.netfilter.nf_conntrack_tcp_timeout_time_wait = 10
net.netfilter.nf_conntrack_tcp_timeout_close = 8
net.netfilter.nf_conntrack_tcp_timeout_max_retrans = 30
net.netfilter.nf_conntrack_tcp_timeout_unacknowledged = 30
net.netfilter.nf_conntrack_tcp_loose = 1
net.netfilter.nf_conntrack_tcp_be_liberal = 0
net.netfilter.nf_conntrack_tcp_max_retrans = 3
net.netfilter.nf_conntrack_udp_timeout = 12
net.netfilter.nf_conntrack_udp_timeout_stream = 18
net.netfilter.nf_conntrack_icmp_timeout = 8
net.netfilter.nf_conntrack_acct = 1
net.netfilter.nf_conntrack_max = 1048576
net.netfilter.nf_conntrack_count = 7645
net.netfilter.nf_conntrack_buckets = 16384
net.netfilter.nf_conntrack_checksum = 1
net.netfilter.nf_conntrack_log_invalid = 0
net.netfilter.nf_conntrack_expect_max = 256