自用优化的 sysctl.conf 配置 @2018.03.17

sysctl.conf

# sysctl settings are defined through files in
# /usr/lib/sysctl.d/, /run/sysctl.d/, and /etc/sysctl.d/.
#
# Vendors settings live in /usr/lib/sysctl.d/.
# To override a whole file, create a new file with the same in
# /etc/sysctl.d/ and put new settings there. To override
# only specific settings, add a file with a lexically later
# name in /etc/sysctl.d/ and put new settings there.
#
# For more information, see sysctl.conf(5) and sysctl.d(5).
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

vm.swappiness = 0
net.ipv4.neigh.default.gc_stale_time=120

# see details in https://help.aliyun.com/knowledge_detail/39428.html
net.ipv4.ip_forward = 0
net.ipv4.conf.all.rp_filter=0
net.ipv4.conf.default.rp_filter=1
net.ipv4.conf.default.accept_source_route = 0
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_announce=2
net.ipv4.conf.all.arp_announce=2

# see details in https://help.aliyun.com/knowledge_detail/41334.html
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.tcp_syncookies = 1

net.ipv4.icmp_echo_ignore_all=1

kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
kernel.softlockup_panic = 1
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.numa_balancing = 0

net.ipv4.netfilter.ip_conntrack_tcp_timeout_established = 1800
net.ipv4.ip_conntrack_max = 16777216   #如果使用默认参数,容易出现网络丢包
net.ipv4.netfilter.ip_conntrack_max = 16777216   #如果使用默认参数,容易出现网络丢包
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_sack = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_wmem = 8192 4336600 873200
net.ipv4.tcp_rmem = 32768 4336600 873200
net.core.netdev_max_backlog =  262144
net.core.somaxconn = 262144
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_fin_timeout=30   #改系統默认的TIMEOUT时间
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_tw_recycle = 1  #开启TCP连接中TIME-WAIT sockets的快速回收 默认为0 表示关闭
net.ipv4.tcp_tw_reuse = 1   #启重用,允许将TIME-WAIT sockets重新用于新的TCP连接 默认为0表示关闭
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.ip_local_port_range = 1024  65535
net.ipv4.conf.all.promote_secondaries = 1
net.ipv4.conf.default.promote_secondaries = 1
net.ipv6.neigh.default.gc_thresh3 = 4096 
net.ipv4.neigh.default.gc_thresh3 = 4096