mqtt支持100W长连接参数调优

一．消息推送节点服务器参数优化
1 调整tcp参数
vi /etc/sysctl.conf

#限制一个进程可以拥有的VMA(虚拟内存区域)的数量
vm.max_map_count = 655360

net.core.somaxconn = 1000000
net.core.rmem_default = 262144
net.core.wmem_default = 262144
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.somaxconn = 10000
net.core.netdev_max_backlog = 20000
net.ipv4.tcp_rmem = 7168 11264 16777216
net.ipv4.tcp_wmem = 7168 11264 16777216
net.ipv4.tcp_mem = 786432 2097152 3145728
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_fin_timeout = 60
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_max_orphans = 131072
net.ipv4.tcp_max_tw_buckets=10000
fs.file-max = 1000000
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_keepalive_probes=3
net.ipv4.tcp_syn_retries=2
net.ipv4.tcp_orphan_retries=3

2 调整文件句柄数
vi /etc/security/limits.conf

soft  nofile 1048576
hard  nofile  1048576

3 调整jvm配置
修改
echo "100000" > /proc/sys/kernel/threads-max
echo "100000" > /proc/sys/kernel/pid_max （默认32768）
echo "200000" > /proc/sys/vm/max_map_count （默认65530）

修改
/etc/security/limits.conf * - nproc 999999
/etc/security/limits.conf * - nofile 999999

以上1和2执行完毕后，运行/sbin/sysctl -p ，并重启服务器reboot， 同时注意防火墙关闭