生产环境常用内核参数

net.ipv4.ip_forward = 0     #关闭数据包转发
net.ipv4.conf.default.rp_filter = 0
net.ipv4.conf.all.rp_filter = 0
net.ipv4.conf.eth0.rp_filter = 0
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
vm.swappiness = 0
kernel.msgmnb = 655360
kernel.msgmax = 655360
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
net.ipv4.tcp_syncookies = 1     #开启SYN Cookies，当出现SYN等待队列溢出时，启用cookies来处理。
net.ipv4.tcp_sack = 1
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_max_syn_backlog = 819200
net.ipv4.tcp_retrans_collapse = 0
net.ipv4.tcp_wmem = 4096 65536 8388608
net.ipv4.tcp_rmem = 4096 65536 8388608
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_window_scaling = 1     #tcp/ip会话的滑动窗口大小是否可变
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_synack_retries = 1     #在放弃连接之前所送出的 SYN+ACK 数目
net.ipv4.tcp_syn_retries = 1        #对于一个新建连接，内核要发送多少个 SYN 连接请求才决定放弃
net.ipv4.tcp_tw_recycle = 0         #关闭快速 TIME-WAIT sockets 回收
net.ipv4.tcp_fin_timeout = 1        #对于本端断开的socket连接，TCP保持在FIN-WAIT-2状态的时间。对方可能会断开连接或一直不结束连接或不可预料的进程死亡
net.ipv4.tcp_tw_reuse = 0       #是否允许重新应用处于TIME-WAIT状态的socket用于新的TCP连接(这个对快速重启动某些服务,而启动后提示端口已经被使用的情形非常有帮助)
fs.file-max = 2048000
kernel.panic = 5        #内核panic时，5秒后自动重启
net.core.netdev_max_backlog = 262144
fs.aio-max-nr = 1048576
net.core.somaxconn = 8192       #端口监听队列的长度