TCP内核调优

vi /etc/sysctl.conf
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net.ipv4.tcp_congestion_control = bbr
net.core.default_qdisc = fq
 
# Core memory defaults and maximums (Global caps)
net.core.rmem_default = 262144
net.core.rmem_max = 134217728
net.core.wmem_default = 262144
net.core.wmem_max = 134217728
 
# TCP specific memory (Min, Default, Max aligned to core max)
net.ipv4.tcp_rmem = 4096 131072 134217728
net.ipv4.tcp_wmem = 4096 131072 134217728
 
# This limits local queue latency to 16KB without killing throughput speed
net.ipv4.tcp_notsent_lowat = 16384
 
# 自动减少缓冲区为原来的1/2以改善缓冲区膨胀
net.ipv4.tcp_adv_win_scale = 1
 
# 减少重传超时（高延迟链路需要更长的超时）
net.ipv4.tcp_retries2 = 8 
 
# 时间戳和窗口缩放（必须开启）
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1

修改默认MTU

vi /etc/netplan/50-cloud-init.yaml
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network:
  version: 2
  ethernets:
    enp0s6:
      match:
        macaddress: "02:00:17:06:a9:b5"
      dhcp4: true
      set-name: "enp0s6"
      dhcp4-overrides:
        use-dns: false
      nameservers:
        addresses:
          - 1.1.1.1
          - 2606:4700:4700::1111
      mtu: 1500

修改fq quantum

vi /etc/networkd-dispatcher/routable.d/50-ifup-hooks
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#!/bin/bash
# 赋予执行权限: chmod +x /etc/networkd-dispatcher/routable.d/50-ifup-hooks
# 启动: systemctl enable --now networkd-dispatcher
 
IFACE_NAME="enp0s6"
 
# 检查网卡是否存在，避免报错
if [ ! -d "/sys/class/net/$IFACE_NAME" ]; then
    echo "Interface $IFACE_NAME not found."
    exit 0
fi
 
if [ "$IFACE" == "$IFACE_NAME" ] || [ -z "$IFACE" ]; then
    # 1. 自动检测物理发送队列(TX Queues)数量
    # 统计 /sys/class/net/enp0s6/queues/ 下以 tx- 开头的目录数量
    TX_COUNT=$(ls -d /sys/class/net/$IFACE_NAME/queues/tx-* 2>/dev/null | wc -l)
    
    echo "Detected $TX_COUNT TX queues on $IFACE_NAME"
 
    # 清除旧规则
    tc qdisc del dev $IFACE_NAME root 2>/dev/null
 
    if [ "$TX_COUNT" -gt 1 ]; then
        # --- 多队列模式 (Multi-Queue) ---
        echo "Applying MQ + FQ for multi-queue..."
        tc qdisc replace dev $IFACE_NAME root handle 1: mq
        
        # 仅针对实际存在的队列进行循环配置
        for ((i=1; i<=TX_COUNT; i++)); do
            tc qdisc replace dev $IFACE_NAME parent 1:$i fq quantum 18028 initial_quantum 90140
        done
    else
        # --- 单队列模式 (Single-Queue) ---
        echo "Applying FQ for single-queue..."
        # 直接在 root 上应用 fq
        tc qdisc replace dev $IFACE_NAME root fq quantum 18028 initial_quantum 90140
    fi
fi