磐维数据库部署之内核参数优化
中国移动磐维数据库（ChinaMobileDB），简称“磐维数据库”（CMDB）。是中国移动信息技术中心首个基于中国本土开源数据库打造的面向ICT基础设施的自研数据库产品。
其产品内核能力基于华为 OpenGauss 开源软件，并进一步提升了系统稳定性。
本文将介绍磐维数据库部署之间要进行的内核参数优化，介绍相关参数的作用。
vi /etc/sysctl.conf
1. panweidb
net.ipv4.tcp_max_tw_buckets = 10000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_keepalive_time = 30
net.ipv4.tcp_keepalive_probes = 9
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_retries1 = 5
net.ipv4.tcp_syn_retries = 5
net.ipv4.tcp_synack_retries = 5
net.ipv4.tcp_retries2 = 12
vm.overcommit_memory = 0
net.ipv4.tcp_rmem = 8192 250000 16777216
net.ipv4.tcp_wmem = 8192 250000 16777216
net.core.wmem_max = 21299200
net.core.rmem_max = 21299200
net.core.wmem_default = 21299200
net.core.rmem_default = 21299200
net.ipv4.ip_local_port_range = 26000 65535
kernel.sem = 250 6400000 1000 25600
net.core.somaxconn = 65535
net.ipv4.tcp_syncookies = 1
net.core.netdev_max_backlog = 65535
net.ipv4.tcp_max_syn_backlog = 65535
net.ipv4.tcp_fin_timeout = 60
kernel.shmall = 1073741824
kernel.shmmax = 751619276800
net.ipv4.tcp_sack = 1
net.ipv4.tcp_timestamps = 1
vm.extfrag_threshold = 500
vm.overcommit_ratio = 90
vm.swappiness = 0
