Centos系统调优

Linux系统优化

1、最大文件打开数

ulimit -a

ulimit -n 100000

ulimit -u 65535

可经过修改启动文件：

vi /etc/rc.local;

二，调优最大TCP链接数

vim /etc/sysctl.conf

# Increase system IP port limits to allow for more connections

# 调高系统的 IP 以及端口数据限制，从能够接受更多的链接

net.ipv4.ip_local_port_range = 2000 65000

net.ipv4.tcp_window_scaling = 1

# number of packets to keep in backlog before the kernel starts dropping them

# 设置协议栈能够缓存的报文数阀值，超过阀值的报文将被内核丢弃

net.ipv4.tcp_max_syn_backlog = 3240000

# increase socket listen backlog

# 调高 socket 侦听数阀值

net.core.somaxconn = 3240000

net.ipv4.tcp_max_tw_buckets = 1440000

# Increase TCP buffer sizes

# 调大 TCP 存储大小

net.core.rmem_default = 8388608

net.core.rmem_max = 16777216

net.core.wmem_max = 16777216

net.ipv4.tcp_rmem = 4096 87380 16777216

net.ipv4.tcp_wmem = 4096 65536 16777216

net.ipv4.tcp_congestion_control = cubic

 

每次修订配置以后都须要执行如下命令使之生效.

sysctl -p /etc/sysctl.conf