nginx高并发系统优化基础

1系统层面优化

在系统内核文件修改/etc/sysctl.conf

# Auto-enabled by xs-tools:install.sh
net.ipv4.conf.all.arp_notify=1
net.ipv4.ip_forward=1
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1

#关闭ipv6
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1

#决定检查过期多久邻居条目
net.ipv4.neigh.default.gc_stale_time=120

#使用arp_announce / arp_ignore解决ARP映射问题
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.all.arp_announce=2
net.ipv4.conf.lo.arp_announce=2
net.ipv4.icmp_echo_ignore_broadcasts = 1
net.ipv4.icmp_ignore_bogus_error_responses = 1

#处理无源路由的包
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0

#core文件名中添加pid作为扩展名
kernel.core_uses_pid = 1
net.ipv4.tcp_syncookies = 1

#修改消息队列长度
kernel.msgmnb = 65536
kernel.msgmax = 65536

#timewait的数量，默认180000
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.tcp_sack = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216

#限制仅仅是为了防止简单的DoS 攻击
net.ipv4.tcp_max_orphans = 3276800

#未收到客户端确认信息的连接请求的最大值
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_timestamps = 0

#内核放弃建立连接之前发送SYNACK 包的数量
net.ipv4.tcp_synack_retries = 1

#内核放弃建立连接之前发送SYN 包的数量
net.ipv4.tcp_syn_retries = 1

#启用timewait 快速回收
net.ipv4.tcp_tw_recycle = 1

#开启重用。允许将TIME-WAIT sockets 重新用于新的TCP 连接
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_fin_timeout = 1

sysctl -p

ulimit -n 30000  临时设置文件打开最大数

永久修改

/etc/security/limits.conf

* soft nofile  65536
* hard nofile 65536
* soft nproc 65536
* hard nproc 65536
 
*             代表针对所有用户
noproc     是代表最大进程数
nofile     是代表最大文件打开数

nginx配置文件

worker_rlimit_nofile10000;（允许打开多少个文件全局区）

keepalive_timeout  0;（高并发选择0，如60s可减少非高并发可减少TCP频繁握手）