.. tiêu đề: Tham khảo điều chỉnh hệ thống TCP TCP của Linux
.. sên: linux-tcp-sysctl-reference
.. ngày: 27-03-2026 12:00:00 UTC
.. tags: linux, tcp, sysctl, hiệu suất, kernel, máy tính, công cụ
.. thể loại: Máy tính
.. liên kết:
.. mô tả: Hướng dẫn tham số net.ipv4.tcp_* và net.core.* tương tác của Linux với các cài đặt trước khối lượng công việc để truyền hàng loạt, RPC nhạy cảm với độ trễ, máy chủ web kết nối cao và mạng WAN đường truyền dài.
.. loại: văn bản
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<div class="calc-container">
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<h2>Tham khảo điều chỉnh hệ thống TCP TCP của Linux</h2>
<p>Tương tác<code style="color:rgba(255,255,255,0.9)">net.ipv4.tcp_*</code>Và<code style="color:rgba(255,255,255,0.9)">net.core.*</code>hướng dẫn tham số với các cài đặt trước khối lượng công việc để truyền số lượng lớn, RPC nhạy cảm với độ trễ, máy chủ web kết nối cao và mạng WAN có đường truyền dài.</p>
<div class="input-grid">
<div class="input-group">
<label>Tìm kiếm / Lọc</label>
<input id="searchInput" oninput="filterParams(this.value)" placeholder="Search parameters..." type="text"/>
</div>
<div class="input-group">
<label>Cài đặt trước khối lượng công việc</label>
<div class="preset-row" id="presetRow"></div>
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</div>
<div class="result-section">
<div class="section-header">Thông số hệ thống TCP</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()">Sao chép tất cả các tham số được hiển thị dưới dạng lệnh sysctl</button>
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</div>
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        name: 'net.ipv4.tcp_congestion_control',
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    },
    {
        name: 'net.ipv4.tcp_window_scaling',
        desc: 'Enable TCP window scaling (RFC 1323). Required for windows > 65535 bytes.',
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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',
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        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.',
        default: '1',
        presets: { bulk: '1', rpc: '1', web: '1', wan: '1' },
        range: '0 or 1',
        tags: ['sack', 'loss', 'recovery'],
        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        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.',
        default: '1024',
        presets: {
            bulk: '1024',
            rpc: '4096',
            web: '65536',
            wan: '1024',
        },
        range: '128 – 65536 (limited by system memory)',
        tags: ['syn', 'connection', 'backlog'],
        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.',
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            rpc: '8192',
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        range: '128 – 65535',
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        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        name: 'net.ipv4.tcp_tw_reuse',
        desc: 'Allow reuse of TIME_WAIT sockets for new connections when safe (requires timestamps). Reduces port exhaustion under heavy connection churn.',
        default: '2',
        presets: {
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            rpc: '1',
            web: '1',
            wan: '2',
        },
        range: '0 (disable), 1 (enable for loopback), 2 (enable for all)',
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        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
    {
        name: 'net.ipv4.tcp_fin_timeout',
        desc: 'Time (seconds) a socket stays in FIN_WAIT_2 state before being forcibly closed. Reduce to reclaim ports faster under high connection rates.',
        default: '60',
        presets: {
            bulk: '60',
            rpc: '15',
            web: '15',
            wan: '60',
        },
        range: '5 – 120 seconds',
        tags: ['fin', 'timeout', 'connection'],
        doc: 'https://www.kernel.org/doc/html/latest/networking/ip-sysctl.html',
    },
];

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