OpenCloud

TCP 튜닝 -  CENTOS7

net.ipv4.tcp_congestion_control = bbr 적용을 위해 커널 4.15 로 업그레이드 (4.9이상 필요)

rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm 
yum --disablerepo="*" --enablerepo="elrepo-kernel" list available
yum --enablerepo=elrepo-kernel -y install kernel-ml
grub2-set-default 0
#리부팅 커널 버전 확인
reboot
uname -sr 

상기 커널 업그레이드를 할수 없다면 net.ipv4.tcp_congestion_control = cubic 로 변경 하거나 지운다(default가 cubic)

echo "net.ipv4.ip_forward = 1" > /etc/sysctl.d/ip_forward.conf

cat << EOF > /etc/sysctl.d/nettune.conf
net.core.rmem_default = 524288
net.core.wmem_default = 524288
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.netdev_max_backlog = 30000
net.core.somaxconn = 1024
net.core.default_qdisc = fq
net.ipv4.tcp_rmem = 262144 524288 16777216
net.ipv4.tcp_wmem = 262144 524288 16777216
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_max_syn_backlog = 1024
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_max_tw_buckets = 1800000
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fastopen = 3
net.ipv4.tcp_congestion_control = bbr
EOF

sysctl --system
#sysctl -p /etc/sysctl.d/ip_forward.conf
#sysctl -p /etc/sysctl.d/nettune.conf

http://meetup.toast.com/posts/55

https://www.tecmint.com/increase-linux-server-internet-speed-with-tcp-bbr/

https://www.vultr.com/docs/how-to-deploy-google-bbr-on-centos-7

iperf3

#클라이언트
iperf3 -V -c 10.178.31.240 -b 1G --get-server-output -P 5
iperf3 -V -c 10.178.31.240 -b 1G --get-server-output --udp -P 5
#서버
iperf3 -V -s