/etc/sysctl.conf

net.core.somaxconn = 10000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.ip_local_port_range = 1024 65023
net.ipv4.tcp_max_syn_backlog = 10240
net.ipv4.tcp_max_tw_buckets = 400000
net.ipv4.tcp_max_orphans = 60000
net.ipv4.tcp_synack_retries = 3
net.ipv4.tcp_fin_timeout = 20
net.ipv4.tcp_tw_recycle = 1