centos内核socket优化

参考：  
http://blog.csdn.net/lcx46/article/details/12418873  
http://blog.sina.com.cn/s/blog_4152a9f50100mo8p.html

0. 服务器配置

系统 centos 7
内存 4G
CPU 4核

1. 修改配置文件(/etc/sysctl.conf)

vi /etc/sysctl.conf #修改配置文件
sysctl -p #配置生效

参考配置

net.core.netdev_max_backlog = 30000
net.core.somaxconn = 262144
net.core.rmem_default = 8388608
net.core.wmem_default = 8388608
net.core.rmem_max=16777216
net.core.wmem_max=16777216
net.ipv4.ip_local_port_range = 1024 65536
net.ipv4.ip_conntrack_max = 131070
net.ipv4.tcp_mem = 131072 2262144 524288
net.ipv4.tcp_rmem=4096 8192 4194304
net.ipv4.tcp_wmem=4096 8192 4194304
net.ipv4.tcp_fin_timeout = 10
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1
net.ipv4.tcp_no_metrics_save=1
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_orphans = 262144
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_synack_retries = 2
net.ipv4.tcp_syn_retries = 2
net.ipv4.netfilter.ip_conntrack_tcp_timeout_established=1800
net.ipv4.netfilter.ip_conntrack_max=131070
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
kernel.randomize_va_space = 1
kernel.exec-shield = 1
net.ipv4.ip_forward = 0
net.ipv4.neigh.default.gc_stale_time=120
net.ipv4.conf.default.accept_source_route = 0
net.ipv4.conf.default.rp_filter=0
net.ipv4.conf.all.rp_filter=0  
net.ipv4.conf.all.arp_announce=2    
net.ipv4.conf.lo.arp_announce=2

2. 调整系统资源－－最大文件句柄数

echo -ne "
* soft nofile 65536
* hard nofile 65536
" >>/etc/security/limits.conf