{"id":37125,"date":"2025-04-18T10:50:18","date_gmt":"2025-04-18T02:50:18","guid":{"rendered":"https:\/\/www.yunshan.net\/blog\/?p=37125"},"modified":"2025-04-18T10:50:18","modified_gmt":"2025-04-18T02:50:18","slug":"%e4%bd%bf%e7%94%a8ebpf%e8%bf%9b%e8%a1%8c%e7%bd%91%e7%bb%9c%e6%8b%a5%e5%a1%9e%e6%8e%a7%e5%88%b6%e7%9a%84%e6%8a%80%e5%b7%a7%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/www.yunshan.net\/blog\/archives\/37125.html","title":{"rendered":"\u4f7f\u7528eBPF\u8fdb\u884c\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u7684\u6280\u5de7\uff1f"},"content":{"rendered":"<p style=\"text-align: center;\">\n<p><img decoding=\"async\" src=\"https:\/\/www.yunshan.net\/blog\/wp-content\/uploads\/2025\/04\/Ef9p45.jpg\" alt=\"\u4f7f\u7528eBPF\u8fdb\u884c\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u7684\u6280\u5de7\uff1f\" ><\/p>\n<\/p>\n<hr>\n<p>\u5728\u6570\u5b57\u7ecf\u6d4e\u7684\u6d6a\u6f6e\u4e0b\uff0c\u7f51\u7edc\u6027\u80fd\u5df2\u6210\u4e3a\u4f01\u4e1a\u7ade\u4e89\u529b\u7684\u5173\u952e\u56e0\u7d20\u3002\u4ece\u4e91\u8ba1\u7b97\u5230\u8fb9\u7f18\u8ba1\u7b97\uff0c\u4ece5G\u5230\u7269\u8054\u7f51\uff0c<strong>\u4f4e\u5ef6\u8fdf\u3001\u9ad8\u541e\u5410<\/strong>\u7684\u7f51\u7edc\u4f20\u8f93\u9700\u6c42\u4e0d\u65ad\u6500\u5347\u3002\u7136\u800c\uff0c\u4f20\u7edf\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u673a\u5236\u5982TCP Reno\u6216CUBIC\uff0c\u6b63\u9762\u4e34\u7740\u52a8\u6001\u73af\u5883\u9002\u5e94\u6027\u5dee\u3001\u5185\u6838\u8fed\u4ee3\u5468\u671f\u957f\u7b49\u74f6\u9888\u3002\u5982\u4f55\u5728\u4e0d\u91cd\u542f\u670d\u52a1\u3001\u4e0d\u4fee\u6539\u5185\u6838\u7684\u524d\u63d0\u4e0b\u5b9e\u73b0<strong>\u5b9e\u65f6\u7cbe\u51c6\u7684\u6d41\u91cf\u8c03\u63a7<\/strong>\uff1f<strong><a href=\"https:\/\/www.yunshan.net\/\"   target=\"_blank\" style=\"color:blue\">eBPF<\/a><\/strong>\uff08\u6269\u5c55\u4f2f\u514b\u5229\u6570\u636e\u5305\u8fc7\u6ee4\u5668\uff09\u6280\u672f\u7684\u51fa\u73b0\uff0c\u4e3a\u8fd9\u4e00\u96be\u9898\u63d0\u4f9b\u4e86\u7834\u5c40\u4e4b\u9053\u3002<\/p>\n<p>\u672c\u6587\u5c06\u6df1\u5165\u63a2\u8ba8\u5982\u4f55\u5229\u7528<a href=\"https:\/\/www.yunshan.net\/\"   target=\"_blank\" style=\"color:blue\">eBPF<\/a>\u7684\u53ef\u7f16\u7a0b\u6027\u548c\u5185\u6838\u7ea7\u89c2\u6d4b\u80fd\u529b\uff0c\u6784\u5efa<strong>\u81ea\u9002\u5e94\u3001\u7ec6\u7c92\u5ea6\u7684\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u65b9\u6848<\/strong>\uff0c\u5e76\u901a\u8fc7\u5b9e\u9645\u6848\u4f8b\u63ed\u793a\u5176\u5728\u73b0\u4ee3\u57fa\u7840\u8bbe\u65bd\u4e2d\u7684\u5b9e\u8df5\u4ef7\u503c\u3002<\/p>\n<hr>\n<h3 id=\"\u4e00-\u4e3a\u4ec0\u4e48ebpf\u662f\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u7684-\u6e38\u620f\u89c4\u5219\u6539\u53d8\u8005\">\u4e00\u3001\u4e3a\u4ec0\u4e48eBPF\u662f\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u7684\u201c\u6e38\u620f\u89c4\u5219\u6539\u53d8\u8005\u201d\uff1f<\/h3>\n<p><strong>eBPF<\/strong>\u5141\u8bb8\u5f00\u53d1\u8005\u5728\u5185\u6838\u4e2d\u5b89\u5168\u5730\u8fd0\u884c\u6c99\u76d2\u5316\u7a0b\u5e8f\uff0c\u65e0\u9700\u4fee\u6539\u5185\u6838\u6e90\u7801\u6216\u52a0\u8f7d\u5185\u6838\u6a21\u5757\u3002\u8fd9\u4e00\u7279\u6027\u5f7b\u5e95\u6539\u53d8\u4e86\u4f20\u7edf\u7f51\u7edc\u4f18\u5316\u7684\u65b9\u5f0f\uff1a<\/p>\n<ol>\n<li><strong>\u96f6\u4fb5\u5165\u89c2\u6d4b<\/strong>\uff1a\u901a\u8fc7\u6302\u8f7deBPF\u7a0b\u5e8f\u5230<code>tcp_congestion_ops<\/code>\u7b49\u5173\u952e\u6570\u636e\u7ed3\u6784\uff0c\u53ef\u5b9e\u65f6\u6355\u83b7\u62e5\u585e\u7a97\u53e3\uff08CWND\uff09\u3001\u5f80\u8fd4\u65f6\u95f4\uff08RTT\uff09\u7b49\u6838\u5fc3\u6307\u6807\uff0c\u800c\u4f20\u7edf\u65b9\u6848\u4f9d\u8d56\u65e5\u5fd7\u6216\u91c7\u6837\uff0c\u5b58\u5728\u76f2\u533a\uff1b\n<\/li>\n<li><strong>\u52a8\u6001\u7b56\u7565\u90e8\u7f72<\/strong>\uff1aeBPF\u7a0b\u5e8f\u53ef\u901a\u8fc7\u70ed\u66f4\u65b0\u52a8\u6001\u8c03\u6574\u62e5\u585e\u7b97\u6cd5\u53c2\u6570\uff0c\u751a\u81f3\u66ff\u6362\u7b97\u6cd5\u903b\u8f91\uff0c\u907f\u514d\u56e0\u5185\u6838\u7248\u672c\u8fed\u4ee3\u5bfc\u81f4\u7684\u517c\u5bb9\u6027\u95ee\u9898\uff1b\n<\/li>\n<li><strong>\u8de8\u534f\u8bae\u6808\u534f\u4f5c<\/strong>\uff1a\u501f\u52a9eBPF\u7684<strong>XDP<\/strong>\uff08eXpress Data Path\uff09\u548c<code>tc<\/code>\uff08\u6d41\u91cf\u63a7\u5236\uff09\u5b50\u7cfb\u7edf\uff0c\u53ef\u5728\u6570\u636e\u5305\u5230\u8fbe\u534f\u8bae\u6808\u524d\u6267\u884c\u8fc7\u6ee4\u6216\u91cd\u5b9a\u5411\uff0c\u51cf\u5c11\u5904\u7406\u5ef6\u8fdf\u3002\n<\/li>\n<\/ol>\n<p>\u67d0\u4e91\u670d\u52a1\u5546\u901a\u8fc7eBPF\u91cd\u5199BBR\u7b97\u6cd5\u7684\u5e26\u5bbd\u63a2\u6d4b\u903b\u8f91\uff0c\u5728\u7a81\u53d1\u6d41\u91cf\u573a\u666f\u4e0b\u5c06\u541e\u5410\u91cf\u63d0\u534740%\uff0c\u800c\u4f20\u7edf\u65b9\u6848\u9700\u91cd\u65b0\u7f16\u8bd1\u5185\u6838\u5e76\u91cd\u542f\u8282\u70b9\u3002<\/p>\n<hr>\n<h3 id=\"\u4e8c-ebpf\u5b9e\u73b0\u62e5\u585e\u63a7\u5236\u7684\u56db\u5927\u6838\u5fc3\u6280\u5de7\">\u4e8c\u3001eBPF\u5b9e\u73b0\u62e5\u585e\u63a7\u5236\u7684\u56db\u5927\u6838\u5fc3\u6280\u5de7<\/h3>\n<h4 id=\"1-\u5185\u6838\u6001\u5b9e\u65f6\u6570\u636e\u91c7\u96c6\u4e0e\u53cd\u9988\">1. <strong>\u5185\u6838\u6001\u5b9e\u65f6\u6570\u636e\u91c7\u96c6\u4e0e\u53cd\u9988<\/strong><\/h4>\n<p>\u4f20\u7edf\u62e5\u585e\u63a7\u5236\u4f9d\u8d56\u7528\u6237\u6001\u5de5\u5177\uff08\u5982<code>ss<\/code>\u3001<code>iproute2<\/code>\uff09\u7684\u5468\u671f\u6027\u91c7\u6837\uff0c\u96be\u4ee5\u6355\u6349\u77ac\u65f6\u62e5\u585e\u4e8b\u4ef6\u3002\u901a\u8fc7eBPF\u7684<code>kprobe<\/code>\u548c<code>tracepoint<\/code>\uff0c\u53ef\u76f4\u63a5\u5728\u5185\u6838\u4e2d\u6ce8\u5165\u4ee5\u4e0b\u63a2\u9488\uff1a<\/p>\n<ul>\n<li><strong>TCP\u72b6\u6001\u673a\u8ddf\u8e2a<\/strong>\uff1a\u5728<code>tcp_enter_cwr<\/code>\uff08\u8fdb\u5165\u62e5\u585e\u72b6\u6001\uff09\u65f6\u89e6\u53d1eBPF\u7a0b\u5e8f\uff0c\u5b9e\u65f6\u7f29\u5c0f\u62e5\u585e\u7a97\u53e3\uff1b\n<\/li>\n<li><strong>RTT\u52a8\u6001\u8ba1\u7b97<\/strong>\uff1a\u6302\u94a9<code>tcp_ack<\/code>\u51fd\u6570\uff0c\u4f7f\u7528\u6ed1\u52a8\u7a97\u53e3\u7b97\u6cd5\u8ba1\u7b97\u7cbe\u786e\u7684RTT\u5747\u503c\uff0c\u66ff\u4ee3\u4f20\u7edf\u56fa\u5b9a\u6743\u91cd\u6ee4\u6ce2\uff1b\n<\/li>\n<li><strong>\u5e26\u5bbd\u5229\u7528\u7387\u76d1\u63a7<\/strong>\uff1a\u5728XDP\u5c42\u7edf\u8ba1\u5355\u4f4d\u65f6\u95f4\u5185\u901a\u8fc7\u7f51\u5361\u961f\u5217\u7684\u6570\u636e\u91cf\uff0c\u52a8\u6001\u8c03\u6574\u53d1\u5305\u901f\u7387\u3002\n<\/li>\n<\/ul>\n<p>\u67d0CDN\u516c\u53f8\u5229\u7528\u6b64\u65b9\u6cd5\uff0c\u5c06\u89c6\u9891\u6d41\u4f20\u8f93\u7684\u5361\u987f\u7387\u964d\u4f4e\u4e8625%\u3002<\/p>\n<h4 id=\"2-\u52a8\u6001\u62e5\u585e\u7b97\u6cd5\u7684-\u70ed\u63d2\u62d4\">2. <strong>\u52a8\u6001\u62e5\u585e\u7b97\u6cd5\u7684\u201c\u70ed\u63d2\u62d4\u201d<\/strong><\/h4>\n<p>\u901a\u8fc7eBPF\u7684<code>bpf_prog_attach<\/code>\u63a5\u53e3\uff0c\u53ef\u5c06\u81ea\u5b9a\u4e49\u62e5\u585e\u63a7\u5236\u7b97\u6cd5\u4ee5BPF\u7a0b\u5e8f\u7684\u5f62\u5f0f\u52a0\u8f7d\u5230\u5185\u6838\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-c\">SEC(&quot;tcp_congestion_ops\/custom_cca&quot;)  \r\nint BPF_PROG(custom_cong_avoid, struct sock *sk, u32 ack, u32 acked) {  \r\nu32 cwnd = tcp_sk(sk)-&gt;snd_cwnd;  \r\nu32 target = bpf_get_prandom_u32() % 100 + 100; \/\/ \u968f\u673a\u5316\u76ee\u6807\u7a97\u53e3  \r\nif (cwnd &lt; target)  \r\ntcp_slow_start(tp, acked);  \r\nelse  \r\ntcp_cong_avoid_ai(tp, acked);  \r\nreturn 0;  \r\n}  \r\n<\/code><\/pre>\n<p>\u6b64\u4ee3\u7801\u6bb5\u5b9e\u73b0\u4e86\u4e00\u4e2a\u57fa\u4e8e\u968f\u673a\u5316\u7a97\u53e3\u8c03\u6574\u7684\u5b9e\u9a8c\u6027\u7b97\u6cd5\uff0c\u53ef\u7528\u4e8e\u6d4b\u8bd5\u4e0d\u540c\u7f51\u7edc\u6761\u4ef6\u4e0b\u7684\u7a33\u5b9a\u6027\u3002<\/p>\n<h4 id=\"3-\u667a\u80fd\u4e22\u5305\u533a\u5206\u4e0e\u91cd\u4f20\u4f18\u5316\">3. <strong>\u667a\u80fd\u4e22\u5305\u533a\u5206\u4e0e\u91cd\u4f20\u4f18\u5316<\/strong><\/h4>\n<p>\u4f20\u7edf\u7b97\u6cd5\u5c06\u4e22\u5305\u4e00\u5f8b\u89c6\u4e3a\u62e5\u585e\u4fe1\u53f7\uff0c\u4f46\u5728\u65e0\u7ebf\u7f51\u7edc\u6216\u6d45\u7f13\u51b2\u961f\u5217\u573a\u666f\u4e0b\uff0c\u8fd9\u4f1a\u5bfc\u81f4\u8fc7\u5ea6\u964d\u901f\u3002eBPF\u53ef\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u589e\u5f3a\u5224\u522b\u80fd\u529b\uff1a<\/p>\n<ul>\n<li><strong>\u5305\u4e71\u5e8f\u68c0\u6d4b<\/strong>\uff1a\u5728<code>tcp_receive<\/code>\u9636\u6bb5\u6807\u8bb0\u4e71\u5e8f\u62a5\u6587\uff0c\u533a\u5206\u62e5\u585e\u4e22\u5305\u4e0e\u94fe\u8def\u5c42\u4e22\u5305\uff1b\n<\/li>\n<li><strong>ECN\uff08\u663e\u5f0f\u62e5\u585e\u901a\u77e5\uff09\u589e\u5f3a<\/strong>\uff1a\u89e3\u6790IP\u5934\u90e8\u7684ECN\u6807\u5fd7\uff0c\u7ed3\u5408\u5386\u53f2\u6570\u636e\u9884\u6d4b\u62e5\u585e\u8d8b\u52bf\uff1b\n<\/li>\n<li><strong>\u5feb\u901f\u91cd\u4f20\u7b56\u7565<\/strong>\uff1a\u5f53eBPF\u68c0\u6d4b\u5230\u8fde\u7eed3\u4e2a\u91cd\u590dACK\u65f6\uff0c\u7acb\u5373\u89e6\u53d1\u5c40\u90e8\u91cd\u4f20\uff0c\u800c\u975e\u7b49\u5f85\u8d85\u65f6\u3002\n<\/li>\n<\/ul>\n<p>\u67d0\u91d1\u878d\u4ea4\u6613\u7cfb\u7edf\u91c7\u7528\u6b64\u65b9\u6848\u540e\uff0c\u9ad8\u9891\u4ea4\u6613\u5ef6\u8fdf\u6807\u51c6\u5dee\u4ece15ms\u964d\u81f33ms\u4ee5\u5185\u3002<\/p>\n<h4 id=\"4-\u8de8\u5c42\u534f\u540c\u4f18\u5316\">4. <strong>\u8de8\u5c42\u534f\u540c\u4f18\u5316<\/strong><\/h4>\n<p>eBPF\u7684\u5168\u5c40\u53ef\u89c1\u6027\u4f7f\u5176\u80fd\u591f\u534f\u8c03\u7f51\u7edc\u6808\u5404\u5c42\u884c\u4e3a\uff1a<\/p>\n<ul>\n<li><strong>\u5e94\u7528\u5c42\u534f\u8bae\u611f\u77e5<\/strong>\uff1a\u89e3\u6790HTTP\/3\u6216gRPC\u5934\u90e8\uff0c\u4f18\u5148\u4fdd\u969c\u5173\u952e\u8bf7\u6c42\u7684\u5e26\u5bbd\uff1b\n<\/li>\n<li><strong>\u7f51\u5361\u961f\u5217\u7ba1\u7406<\/strong>\uff1a\u4e0eXDP\u7ed3\u5408\uff0c\u5728\u786c\u4ef6\u961f\u5217\u6ee1\u4e4b\u524d\u4e3b\u52a8\u4e22\u5f03\u4f4e\u4f18\u5148\u7ea7\u6570\u636e\u5305\uff1b\n<\/li>\n<li><strong>\u5bb9\u5668\u7f51\u7edc\u96c6\u6210<\/strong>\uff1a\u5728Kubernetes\u4e2d\uff0c\u901a\u8fc7Cilium\u7b49eBPF\u9a71\u52a8\u65b9\u6848\uff0c\u5b9e\u73b0Pod\u7ea7\u522b\u7684\u62e5\u585e\u9694\u79bb\u3002\n<\/li>\n<\/ul>\n<hr>\n<h3 id=\"\u4e09-\u5b9e\u8df5\u6848\u4f8b-ebpf\u5728\u5927\u578b\u7535\u5546\u7684\u79d2\u6740\u573a\u666f\u4e2d\u7684\u5e94\u7528\">\u4e09\u3001\u5b9e\u8df5\u6848\u4f8b\uff1aeBPF\u5728\u5927\u578b\u7535\u5546\u7684\u79d2\u6740\u573a\u666f\u4e2d\u7684\u5e94\u7528<\/h3>\n<p>\u67d0\u7535\u5546\u5e73\u53f0\u5728\u201c\u53cc11\u201d\u671f\u95f4\u9762\u4e34\u7a81\u53d1\u6d41\u91cf\u51b2\u51fb\uff0c\u5176\u539f\u6709TCP CUBIC\u7b97\u6cd5\u5bfc\u81f4\u8d1f\u8f7d\u5747\u8861\u5668\u9891\u7e41\u89e6\u53d1\u62e5\u585e\u5d29\u6e83\u3002\u6280\u672f\u56e2\u961f\u901a\u8fc7eBPF\u5b9e\u65bd\u4ee5\u4e0b\u6539\u9020\uff1a<\/p>\n<ol>\n<li><strong>\u52a8\u6001\u9608\u503c\u8c03\u6574<\/strong>\uff1a\u57fa\u4e8eXDP\u7684\u5b9e\u65f6\u5e26\u5bbd\u76d1\u6d4b\uff0c\u5f53\u5165\u53e3\u6d41\u91cf\u8d85\u8fc7\u7269\u7406\u94fe\u8def\u5bb9\u91cf\u768480%\u65f6\uff0c\u81ea\u52a8\u5207\u6362\u4e3a\u4fdd\u5b88\u7684Reno\u7b97\u6cd5\uff1b\n<\/li>\n<li><strong>\u6d41\u91cf\u67d3\u8272<\/strong>\uff1a\u5bf9\u79d2\u6740API\u8bf7\u6c42\u6dfb\u52a0DSCP\u6807\u8bb0\uff0c\u5728<code>tc<\/code>\u5b50\u7cfb\u7edf\u4e2d\u4f18\u5148\u8c03\u5ea6\uff1b\n<\/li>\n<li><strong>RTT\u9884\u6d4b<\/strong>\uff1a\u4f7f\u7528LSTM\u6a21\u578b\uff08\u901a\u8fc7eBPF-map\u4e0e\u7528\u6237\u6001\u5171\u4eab\u6570\u636e\uff09\u9884\u6d4b\u672a\u6765RTT\u8d8b\u52bf\uff0c\u63d0\u524d\u8c03\u6574\u7a97\u53e3\u5927\u5c0f\u3002\n<\/li>\n<\/ol>\n<p>\u6539\u9020\u540e\uff0c\u6838\u5fc3\u4ea4\u6613\u7cfb\u7edf\u7684\u541e\u5410\u91cf\u5cf0\u503c\u8fbe\u5230\u539f\u6709\u6c34\u5e73\u76842.3\u500d\uff0c\u4e14\u672a\u51fa\u73b0\u96ea\u5d29\u5f0f\u62e5\u585e\u3002<\/p>\n<hr>\n<h3 id=\"\u56db-\u6311\u6218\u4e0e\u6700\u4f73\u5b9e\u8df5\">\u56db\u3001\u6311\u6218\u4e0e\u6700\u4f73\u5b9e\u8df5<\/h3>\n<p>\u5c3d\u7ba1eBPF\u6f5c\u529b\u5de8\u5927\uff0c\u5b9e\u8df5\u4e2d\u4ecd\u9700\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>**\u5185\u6838<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u6570\u5b57\u7ecf\u6d4e\u7684\u6d6a\u6f6e\u4e0b\uff0c\u7f51\u7edc\u6027\u80fd\u5df2\u6210\u4e3a\u4f01\u4e1a\u7ade\u4e89\u529b\u7684\u5173\u952e\u56e0\u7d20\u3002\u4ece\u4e91\u8ba1\u7b97\u5230\u8fb9\u7f18\u8ba1\u7b97\uff0c\u4ece5G\u5230\u7269\u8054\u7f51\uff0c\u4f4e\u5ef6\u8fdf\u3001\u9ad8\u541e\u5410\u7684\u7f51\u7edc\u4f20\u8f93\u9700\u6c42\u4e0d\u65ad\u6500\u5347\u3002\u7136\u800c\uff0c\u4f20\u7edf\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u673a\u5236\u5982TCP Reno\u6216CUBIC\uff0c\u6b63\u9762\u4e34\u7740\u52a8\u6001\u73af\u5883\u9002\u5e94\u6027\u5dee\u3001\u5185\u6838\u8fed\u4ee3\u5468\u671f\u957f\u7b49\u74f6\u9888\u3002\u5982\u4f55\u5728\u4e0d\u91cd\u542f\u670d\u52a1\u3001\u4e0d\u4fee\u6539\u5185\u6838\u7684\u524d\u63d0\u4e0b\u5b9e\u73b0\u5b9e\u65f6\u7cbe\u51c6\u7684\u6d41\u91cf\u8c03\u63a7\uff1feBPF\uff08\u6269\u5c55\u4f2f\u514b\u5229\u6570\u636e\u5305\u8fc7\u6ee4\u5668\uff09\u6280\u672f\u7684\u51fa\u73b0\uff0c\u4e3a\u8fd9\u4e00\u96be\u9898\u63d0\u4f9b\u4e86\u7834\u5c40\u4e4b\u9053\u3002 \u672c\u6587\u5c06\u6df1\u5165\u63a2\u8ba8\u5982\u4f55\u5229\u7528eBPF\u7684\u53ef\u7f16\u7a0b\u6027\u548c\u5185\u6838\u7ea7\u89c2\u6d4b\u80fd\u529b\uff0c\u6784\u5efa\u81ea\u9002\u5e94\u3001\u7ec6\u7c92\u5ea6\u7684\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u65b9\u6848\uff0c\u5e76\u901a\u8fc7\u5b9e\u9645\u6848\u4f8b\u63ed\u793a\u5176\u5728\u73b0\u4ee3\u57fa\u7840\u8bbe\u65bd\u4e2d\u7684\u5b9e\u8df5\u4ef7\u503c\u3002 \u4e00\u3001\u4e3a\u4ec0\u4e48eBPF\u662f\u7f51\u7edc\u62e5\u585e\u63a7\u5236\u7684\u201c\u6e38\u620f\u89c4\u5219\u6539\u53d8\u8005\u201d\uff1f eBPF\u5141\u8bb8\u5f00\u53d1\u8005\u5728\u5185\u6838\u4e2d\u5b89\u5168\u5730\u8fd0\u884c\u6c99\u76d2\u5316\u7a0b\u5e8f\uff0c\u65e0\u9700\u4fee\u6539\u5185\u6838\u6e90\u7801\u6216\u52a0\u8f7d\u5185\u6838\u6a21\u5757\u3002\u8fd9\u4e00\u7279\u6027\u5f7b\u5e95\u6539\u53d8\u4e86\u4f20\u7edf\u7f51\u7edc\u4f18\u5316\u7684\u65b9\u5f0f\uff1a \u96f6\u4fb5\u5165\u89c2\u6d4b\uff1a\u901a\u8fc7\u6302\u8f7deBPF\u7a0b\u5e8f\u5230tcp_congestion_ops\u7b49\u5173\u952e\u6570\u636e\u7ed3\u6784\uff0c\u53ef\u5b9e\u65f6\u6355\u83b7\u62e5\u585e\u7a97\u53e3\uff08CWND\uff09\u3001\u5f80\u8fd4\u65f6\u95f4\uff08RTT\uff09\u7b49\u6838\u5fc3\u6307\u6807\uff0c\u800c\u4f20\u7edf\u65b9\u6848\u4f9d\u8d56\u65e5\u5fd7\u6216\u91c7\u6837\uff0c\u5b58\u5728\u76f2\u533a\uff1b \u52a8\u6001\u7b56\u7565\u90e8\u7f72\uff1aeBPF\u7a0b\u5e8f\u53ef\u901a\u8fc7\u70ed\u66f4\u65b0\u52a8\u6001\u8c03\u6574\u62e5\u585e\u7b97\u6cd5\u53c2\u6570\uff0c\u751a\u81f3\u66ff\u6362\u7b97\u6cd5\u903b\u8f91\uff0c\u907f\u514d\u56e0\u5185\u6838\u7248\u672c\u8fed\u4ee3\u5bfc\u81f4\u7684\u517c\u5bb9\u6027\u95ee\u9898\uff1b \u8de8\u534f\u8bae\u6808\u534f\u4f5c\uff1a\u501f\u52a9eBPF\u7684XDP\uff08eXpress Data Path\uff09\u548ctc\uff08\u6d41\u91cf\u63a7\u5236\uff09\u5b50\u7cfb\u7edf\uff0c\u53ef\u5728\u6570\u636e\u5305\u5230\u8fbe\u534f\u8bae\u6808\u524d\u6267\u884c\u8fc7\u6ee4\u6216\u91cd\u5b9a\u5411\uff0c\u51cf\u5c11\u5904\u7406\u5ef6\u8fdf\u3002 \u67d0\u4e91\u670d\u52a1\u5546\u901a\u8fc7eBPF\u91cd\u5199BBR\u7b97\u6cd5\u7684\u5e26\u5bbd\u63a2\u6d4b\u903b\u8f91\uff0c\u5728\u7a81\u53d1\u6d41\u91cf\u573a\u666f\u4e0b\u5c06\u541e\u5410\u91cf\u63d0\u534740%\uff0c\u800c\u4f20\u7edf\u65b9\u6848\u9700\u91cd\u65b0\u7f16\u8bd1\u5185\u6838\u5e76\u91cd\u542f\u8282\u70b9\u3002 \u4e8c\u3001eBPF\u5b9e\u73b0\u62e5\u585e\u63a7\u5236\u7684\u56db\u5927\u6838\u5fc3\u6280\u5de7 1. \u5185\u6838\u6001\u5b9e\u65f6\u6570\u636e\u91c7\u96c6\u4e0e\u53cd\u9988 \u4f20\u7edf\u62e5\u585e\u63a7\u5236\u4f9d\u8d56\u7528\u6237\u6001\u5de5\u5177\uff08\u5982ss\u3001iproute2\uff09\u7684\u5468\u671f\u6027\u91c7\u6837\uff0c\u96be\u4ee5\u6355\u6349\u77ac\u65f6\u62e5\u585e\u4e8b\u4ef6\u3002\u901a\u8fc7eBPF\u7684kprobe\u548ctracepoint\uff0c\u53ef\u76f4\u63a5\u5728\u5185\u6838\u4e2d\u6ce8\u5165\u4ee5\u4e0b\u63a2\u9488\uff1a TCP\u72b6\u6001\u673a\u8ddf\u8e2a\uff1a\u5728tcp_enter_cwr\uff08\u8fdb\u5165\u62e5\u585e\u72b6\u6001\uff09\u65f6\u89e6\u53d1eBPF\u7a0b\u5e8f\uff0c\u5b9e\u65f6\u7f29\u5c0f\u62e5\u585e\u7a97\u53e3\uff1b RTT\u52a8\u6001\u8ba1\u7b97\uff1a\u6302\u94a9tcp_ack\u51fd\u6570\uff0c\u4f7f\u7528\u6ed1\u52a8\u7a97\u53e3\u7b97\u6cd5\u8ba1\u7b97\u7cbe\u786e\u7684RTT\u5747\u503c\uff0c\u66ff\u4ee3\u4f20\u7edf\u56fa\u5b9a\u6743\u91cd\u6ee4\u6ce2\uff1b \u5e26\u5bbd\u5229\u7528\u7387\u76d1\u63a7\uff1a\u5728XDP\u5c42\u7edf\u8ba1\u5355\u4f4d\u65f6\u95f4\u5185\u901a\u8fc7\u7f51\u5361\u961f\u5217\u7684\u6570\u636e\u91cf\uff0c\u52a8\u6001\u8c03\u6574\u53d1\u5305\u901f\u7387\u3002 \u67d0CDN\u516c\u53f8\u5229\u7528\u6b64\u65b9\u6cd5\uff0c\u5c06\u89c6\u9891\u6d41\u4f20\u8f93\u7684\u5361\u987f\u7387\u964d\u4f4e\u4e8625%\u3002 2. \u52a8\u6001\u62e5\u585e\u7b97\u6cd5\u7684\u201c\u70ed\u63d2\u62d4\u201d \u901a\u8fc7eBPF\u7684bpf_prog_attach\u63a5\u53e3\uff0c\u53ef\u5c06\u81ea\u5b9a\u4e49\u62e5\u585e\u63a7\u5236\u7b97\u6cd5\u4ee5BPF\u7a0b\u5e8f\u7684\u5f62\u5f0f\u52a0\u8f7d\u5230\u5185\u6838\u3002\u4f8b\u5982\uff1a SEC(&quot;tcp_congestion_ops\/custom_cca&quot;) int BPF_PROG(custom_cong_avoid, struct sock *sk, u32 ack, u32 acked) { u32 cwnd = tcp_sk(sk)-&gt;snd_cwnd; u32 target = bpf_get_prandom_u32() % 100 + 100; \/\/ \u968f\u673a\u5316\u76ee\u6807\u7a97\u53e3 if (cwnd &lt; target) tcp_slow_start(tp, acked); else tcp_cong_avoid_ai(tp, 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