Linux内核参数调优

本人在实际工作经过总结，在调优上有一下参数值得使用，特此总结。当然有一些也参考了大佬们的经验所获

系统资源优化

#root账⼾的资源软限制和硬限制
root soft core unlimited
root hard core unlimited
root soft nproc 1000000
root hard nproc 1000000
root soft nofile 1000000
root hard nofile 1000000
root soft memlock 32000
root hard memlock 32000
root soft msgqueue 8192000
root hard msgqueue 8192000
#其他账⼾的资源软限制和硬限制
* soft core unlimited
* hard core unlimited
* soft nproc 1000000
* hard nproc 1000000
* soft nofile 1000000
* hard nofile 1000000
* soft memlock 32000
* hard memlock 32000
* soft msgqueue 8192000
* hard msgqueue 8192000

内核参数优化

# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
#number of pid_max
kernel.pid_max = 1000000
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1
# Disable netfilter on bridges.
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
# Controls the default maxmimum size of a mesage queue
kernel.msgmnb = 65536
# # Controls the maximum size of a message, in bytes
kernel.msgmax = 65536
# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736
# # Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
# TCP kernel paramater
net.ipv4.tcp_mem = 786432 1048576 1572864
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1
# socket buffer
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.netdev_max_backlog = 262144
net.core.somaxconn = 20480
net.core.optmem_max = 81920
# TCP conn
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_syn_retries = 3
net.ipv4.tcp_retries1 = 3
net.ipv4.tcp_retries2 = 15
# tcp conn reuse
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_tw_reuse = 0
net.ipv4.tcp_tw_recycle = 0
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_max_tw_buckets = 20000
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syncookies = 1
# keepalive conn
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.ip_local_port_range = 10001 65000
# swap
vm.overcommit_memory = 0
vm.swappiness = 10

注意：
上面有个参数tcp_tw_recycle，目前在内核4.10以上该参数被遗弃使用，生产环境当中该参数最好设置为0也就是关闭状态。tcp_tw_recycle在高版本内核中弊大于利，应保持系统默认设置，关闭参数。这个文章介绍的不错https://www.cnblogs.com/CtripDBA/p/10860834.html