$npx -y skills add chaterm/terminal-skills --skill tuning系统调优
| 1 | # 系统调优 |
| 2 | |
| 3 | ## 概述 |
| 4 | 内核参数、文件系统、网络优化技能。 |
| 5 | |
| 6 | ## 内核参数调优 |
| 7 | |
| 8 | ### 内存管理 |
| 9 | ```bash |
| 10 | # /etc/sysctl.d/99-memory.conf |
| 11 | |
| 12 | # 减少交换倾向 |
| 13 | vm.swappiness = 10 |
| 14 | |
| 15 | # 脏页刷新 |
| 16 | vm.dirty_ratio = 20 |
| 17 | vm.dirty_background_ratio = 5 |
| 18 | |
| 19 | # 内存过量提交 |
| 20 | vm.overcommit_memory = 1 |
| 21 | vm.overcommit_ratio = 80 |
| 22 | |
| 23 | # 最大内存映射数 |
| 24 | vm.max_map_count = 262144 |
| 25 | |
| 26 | # 应用 |
| 27 | sysctl -p /etc/sysctl.d/99-memory.conf |
| 28 | ``` |
| 29 | |
| 30 | ### 网络调优 |
| 31 | ```bash |
| 32 | # /etc/sysctl.d/99-network.conf |
| 33 | |
| 34 | # TCP 缓冲区 |
| 35 | net.core.rmem_max = 16777216 |
| 36 | net.core.wmem_max = 16777216 |
| 37 | net.ipv4.tcp_rmem = 4096 87380 16777216 |
| 38 | net.ipv4.tcp_wmem = 4096 65536 16777216 |
| 39 | |
| 40 | # 连接队列 |
| 41 | net.core.somaxconn = 65535 |
| 42 | net.core.netdev_max_backlog = 65535 |
| 43 | net.ipv4.tcp_max_syn_backlog = 65535 |
| 44 | |
| 45 | # TIME_WAIT |
| 46 | net.ipv4.tcp_tw_reuse = 1 |
| 47 | net.ipv4.tcp_fin_timeout = 30 |
| 48 | net.ipv4.tcp_max_tw_buckets = 65535 |
| 49 | |
| 50 | # 端口范围 |
| 51 | net.ipv4.ip_local_port_range = 1024 65535 |
| 52 | |
| 53 | # Keep-Alive |
| 54 | net.ipv4.tcp_keepalive_time = 600 |
| 55 | net.ipv4.tcp_keepalive_intvl = 30 |
| 56 | net.ipv4.tcp_keepalive_probes = 3 |
| 57 | ``` |
| 58 | |
| 59 | ### 文件系统 |
| 60 | ```bash |
| 61 | # /etc/sysctl.d/99-fs.conf |
| 62 | |
| 63 | # 文件句柄 |
| 64 | fs.file-max = 2097152 |
| 65 | fs.nr_open = 2097152 |
| 66 | |
| 67 | # inotify |
| 68 | fs.inotify.max_user_watches = 524288 |
| 69 | fs.inotify.max_user_instances = 512 |
| 70 | ``` |
| 71 | |
| 72 | ## 文件描述符限制 |
| 73 | |
| 74 | ### ulimit 配置 |
| 75 | ```bash |
| 76 | # /etc/security/limits.conf |
| 77 | * soft nofile 65535 |
| 78 | * hard nofile 65535 |
| 79 | * soft nproc 65535 |
| 80 | * hard nproc 65535 |
| 81 | |
| 82 | root soft nofile 65535 |
| 83 | root hard nofile 65535 |
| 84 | ``` |
| 85 | |
| 86 | ### systemd 服务 |
| 87 | ```bash |
| 88 | # /etc/systemd/system/myapp.service.d/limits.conf |
| 89 | [Service] |
| 90 | LimitNOFILE=65535 |
| 91 | LimitNPROC=65535 |
| 92 | ``` |
| 93 | |
| 94 | ## 磁盘 IO 调优 |
| 95 | |
| 96 | ### IO 调度器 |
| 97 | ```bash |
| 98 | # 查看当前调度器 |
| 99 | cat /sys/block/sda/queue/scheduler |
| 100 | |
| 101 | # 设置调度器 |
| 102 | echo deadline > /sys/block/sda/queue/scheduler |
| 103 | echo noop > /sys/block/sda/queue/scheduler # SSD |
| 104 | echo mq-deadline > /sys/block/nvme0n1/queue/scheduler |
| 105 | |
| 106 | # 永久设置 (GRUB) |
| 107 | GRUB_CMDLINE_LINUX="elevator=deadline" |
| 108 | ``` |
| 109 | |
| 110 | ### 预读设置 |
| 111 | ```bash |
| 112 | # 查看预读 |
| 113 | blockdev --getra /dev/sda |
| 114 | |
| 115 | # 设置预读 (KB) |
| 116 | blockdev --setra 4096 /dev/sda |
| 117 | ``` |
| 118 | |
| 119 | ### 挂载选项 |
| 120 | ```bash |
| 121 | # /etc/fstab |
| 122 | # SSD 优化 |
| 123 | /dev/sda1 /data ext4 defaults,noatime,nodiratime,discard 0 2 |
| 124 | |
| 125 | # 数据库优化 |
| 126 | /dev/sdb1 /mysql ext4 defaults,noatime,barrier=0 0 2 |
| 127 | ``` |
| 128 | |
| 129 | ## CPU 调优 |
| 130 | |
| 131 | ### CPU 频率 |
| 132 | ```bash |
| 133 | # 查看调速器 |
| 134 | cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor |
| 135 | |
| 136 | # 设置性能模式 |
| 137 | cpupower frequency-set -g performance |
| 138 | |
| 139 | # 或直接设置 |
| 140 | echo performance | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor |
| 141 | ``` |
| 142 | |
| 143 | ### NUMA 优化 |
| 144 | ```bash |
| 145 | # 查看 NUMA 信息 |
| 146 | numactl --hardware |
| 147 | numastat |
| 148 | |
| 149 | # 绑定 NUMA 节点 |
| 150 | numactl --cpunodebind=0 --membind=0 ./program |
| 151 | |
| 152 | # 查看进程 NUMA 分布 |
| 153 | numastat -p PID |
| 154 | ``` |
| 155 | |
| 156 | ### CPU 亲和性 |
| 157 | ```bash |
| 158 | # 查看亲和性 |
| 159 | taskset -p PID |
| 160 | |
| 161 | # 设置亲和性 |
| 162 | taskset -c 0-3 ./program |
| 163 | taskset -pc 0-3 PID |
| 164 | ``` |
| 165 | |
| 166 | ## 常见场景 |
| 167 | |
| 168 | ### 场景 1:Web 服务器优化 |
| 169 | ```bash |
| 170 | # /etc/sysctl.d/99-web.conf |
| 171 | net.core.somaxconn = 65535 |
| 172 | net.ipv4.tcp_max_syn_backlog = 65535 |
| 173 | net.ipv4.tcp_tw_reuse = 1 |
| 174 | net.ipv4.tcp_fin_timeout = 30 |
| 175 | net.core.netdev_max_backlog = 65535 |
| 176 | |
| 177 | # 文件描述符 |
| 178 | fs.file-max = 2097152 |
| 179 | ``` |
| 180 | |
| 181 | ### 场景 2:数据库服务器优化 |
| 182 | ```bash |
| 183 | # /etc/sysctl.d/99-database.conf |
| 184 | vm.swappiness = 1 |
| 185 | vm.dirty_ratio = 40 |
| 186 | vm.dirty_background_ratio = 10 |
| 187 | vm.overcommit_memory = 1 |
| 188 | |
| 189 | # 大页内存 |
| 190 | vm.nr_hugepages = 1024 |
| 191 | ``` |
| 192 | |
| 193 | ### 场景 3:高并发优化 |
| 194 | ```bash |
| 195 | #!/bin/bash |
| 196 | # 一键优化脚本 |
| 197 | |
| 198 | # 网络 |
| 199 | sysctl -w net.core.somaxconn=65535 |
| 200 | sysctl -w net.ipv4.tcp_max_syn_backlog=65535 |
| 201 | sysctl -w net.ipv4.ip_local_port_range="1024 65535" |
| 202 | |
| 203 | # 文件 |
| 204 | sysctl -w fs.file-max=2097152 |
| 205 | |
| 206 | # 内存 |
| 207 | sysctl -w vm.swappiness=10 |
| 208 | ``` |
| 209 | |
| 210 | ## 调优检查 |
| 211 | |
| 212 | | 项目 | 检查命令 | |
| 213 | |------|----------| |
| 214 | | 文件限制 | ulimit -n | |
| 215 | | 网络参数 | sysctl -a \| grep net | |
| 216 | | 内存参数 | sysctl -a \| grep vm | |
| 217 | | IO 调度 | cat /sys/block/*/queue/scheduler | |
| 218 | |
| 219 | ## 故障排查 |
| 220 | |
| 221 | ```bash |
| 222 | # 检查当前限制 |
| 223 | cat /proc/PID/limits |
| 224 | |
| 225 | # 检查打开文件数 |
| 226 | ls /proc/PID/fd | wc -l |
| 227 | lsof -p PID | wc -l |
| 228 | |
| 229 | # 检查网络连接 |
| 230 | ss -s |
| 231 | netstat -an | awk '/tcp/ {print $6}' | sort | uniq -c |
| 232 | ``` |