Kernel parameters for high-load Linux

Edit two config files:


% vi /etc/sysctl.conf

net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
net.ipv4.tcp_syncookies = 1
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
kernel.domainname=servername
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 = 3
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.rmem_default = 1048576
net.core.wmem_default = 1048576
net.core.somaxconn = 16384
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
net.core.netdev_max_backlog = 3000
#net.ipv4.tcp_congestion_control = htcp #for centos 5
net.ipv4.tcp_congestion_control = cubic #for centos 6
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_tw_reuse = 1
net.ipv4.neigh.default.unres_qlen = 6
net.ipv4.neigh.default.proxy_qlen = 96
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.tcp_keepalive_time = 60
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.tcp_keepalive_intvl = 10
fs.file-max = 360000


% vi /etc/security/limits.conf

* soft nofile 360000
* hard nofile 360000

and reboot…
http://wenxueliu.github.io/blog/10/10/2014/linux-tuning/