..标题：Linux TCP Sysctl 调优参考
.. slug: linux-tcp-sysctl-参考
.. 日期: 2026-03-27 12:00:00 世界标准时间
.. 标签：linux、tcp、sysctl、性能、内核、计算器、工具
..类别：计算器
..链接：
.. 描述：交互式 Linux net.ipv4.tcp_* 和 net.core.* 参数指南，其中包含批量传输、延迟敏感的 RPC、高连接 Web 服务器和长宽管 WAN 的工作负载预设。
..类型：文本
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<div class="calc-container">
<div class="calc-header">
<h2>Linux TCP Sysctl 调优参考</h2>
<p>交互的<code style="color:rgba(255,255,255,0.9)">net.ipv4.tcp_*</code>和<code style="color:rgba(255,255,255,0.9)">net.core.*</code>参数指南，其中包含批量传输、延迟敏感的 RPC、高连接 Web 服务器和长宽管 WAN 的工作负载预设。</p>
<div class="input-grid">
<div class="input-group">
<label>搜索/过滤</label>
<input id="searchInput" oninput="filterParams(this.value)" placeholder="Search parameters..." type="text"/>
</div>
<div class="input-group">
<label>工作负载预设</label>
<div class="preset-row" id="presetRow"></div>
</div>
</div>
</div>
<div class="result-section">
<div class="section-header">TCP 系统参数</div>
<div class="section-content" id="paramList">
</div>
<div style="padding: 20px; background: #fafafa; border-top: 1px solid #e0e0e0;">
<button class="copy-all-btn" onclick="copyAll()">将所有显示的参数复制为 sysctl 命令</button>
</div>
</div>
</div>
<script>
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        name: 'net.ipv4.tcp_congestion_control',
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    },
    {
        name: 'net.ipv4.tcp_window_scaling',
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    },
    {
        name: 'net.ipv4.tcp_timestamps',
        desc: 'RFC 1323 timestamps — used for PAWS (protection against wrapped sequence numbers) and RTT measurement.',
        default: '1',
        presets: { bulk: '1', rpc: '1', web: '1', wan: '1' },
        range: '0 (disable), 1 (enable), 2 (enable without ECR)',
        tags: ['rfc1323', 'paws', 'rtt'],
        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        name: 'net.ipv4.tcp_sack',
        desc: 'Selective Acknowledgements (RFC 2018). Allows receiver to inform sender of non-contiguous received segments, improving recovery from multiple losses.',
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        presets: { bulk: '1', rpc: '1', web: '1', wan: '1' },
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    },
    {
        name: 'net.ipv4.tcp_max_syn_backlog',
        desc: 'Maximum number of SYN packets queued per listening socket before dropping. Increase for high connection-rate servers.',
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        presets: {
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            rpc: '4096',
            web: '65536',
            wan: '1024',
        },
        range: '128 – 65536 (limited by system memory)',
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        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        name: 'net.core.somaxconn',
        desc: 'Maximum socket listen backlog (accept queue depth). Application must also set listen() backlog >= this value.',
        default: '4096',
        presets: {
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            rpc: '8192',
            web: '65535',
            wan: '4096',
        },
        range: '128 – 65535',
        tags: ['connection', 'backlog', 'accept', 'core'],
        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        name: 'net.ipv4.tcp_tw_reuse',
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            web: '1',
            wan: '2',
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    },
    {
        name: 'net.ipv4.tcp_fin_timeout',
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        default: '60',
        presets: {
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            rpc: '15',
            web: '15',
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        },
        range: '5 – 120 seconds',
        tags: ['fin', 'timeout', 'connection'],
        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
];

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    list.innerHTML = filtered.map((p, idx) => {
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                    <span><strong>Default:</strong> ${p.default}</span>
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                <div style="margin-top:8px">${tags}</div>
                <div class="copy-block">${cmd} <button class="copy-btn" onclick="copyCmd('${cmd}')">Copy</button></div>
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init();
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