{"id":208390,"date":"2025-08-31T20:41:12","date_gmt":"2025-08-31T12:41:12","guid":{"rendered":"https:\/\/www.server.hk\/blog\/?p=208390"},"modified":"2025-08-31T20:41:12","modified_gmt":"2025-08-31T12:41:12","slug":"%e6%b7%b1%e5%85%a5%e7%90%86%e8%a7%a3-linux-epoll-%e6%a8%a1%e5%9e%8b%ef%bc%9a%e9%ab%98%e6%95%88-i-o-%e5%a4%9a%e8%b7%af%e5%a4%8d%e7%94%a8%e7%9a%84%e5%85%a8%e9%9d%a2%e6%8c%87%e5%8d%97","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/208390\/","title":{"rendered":"\u6df1\u5165\u7406\u89e3 Linux Epoll \u6a21\u578b\uff1a\u9ad8\u6548 I\/O \u591a\u8def\u590d\u7528\u7684\u5168\u9762\u6307\u5357"},"content":{"rendered":"

Linux epoll \u6a21\u578b\u662f\u4e00\u79cd\u7528\u4e8e\u5904\u7406\u9ad8\u6027\u80fd\u7f51\u7edc I\/O \u64cd\u4f5c\u7684\u5f3a\u5927\u673a\u5236\uff0c\u5e7f\u6cdb\u5e94\u7528\u4e8e\u670d\u52a1\u5668\u5e94\u7528\u7a0b\u5e8f\u3002\u672c\u6587\u5c06\u6df1\u5165\u63a2\u8ba8 epoll \u6a21\u578b\uff0c\u4e0e\u5176\u4ed6 I\/O \u65b9\u6cd5\u8fdb\u884c\u6bd4\u8f83\uff0c\u5e76\u63d0\u4f9b\u8be6\u7ec6\u7684\u6280\u672f\u5206\u6790\uff0c\u5e2e\u52a9\u5f00\u53d1\u8005\u4f18\u5316\u5e94\u7528\u7a0b\u5e8f\u4ee5\u5b9e\u73b0\u53ef\u6269\u5c55\u6027\u548c\u9ad8\u6548\u6027\u3002<\/p>\n

Linux I\/O \u7684\u6838\u5fc3\u6982\u5ff5<\/h2>\n

\u8981\u5168\u9762\u7406\u89e3 epoll \u6a21\u578b\uff0c\u5fc5\u987b\u5148\u638c\u63e1 Linux I\/O \u64cd\u4f5c\u7684\u57fa\u7840\u6982\u5ff5\u3002<\/p>\n

\u7528\u6237\u7a7a\u95f4\u4e0e\u5185\u6838\u7a7a\u95f4<\/h3>\n

\u73b0\u4ee3\u64cd\u4f5c\u7cfb\u7edf\uff08\u5305\u62ec Linux\uff09\u4f7f\u7528\u865a\u62df\u5185\u5b58\u5c06\u7528\u6237\u7a7a\u95f4<\/strong>\u548c\u5185\u6838\u7a7a\u95f4<\/strong>\u5206\u9694\u5f00\u3002\u5bf9\u4e8e 32 \u4f4d\u7cfb\u7edf\uff0c\u5176\u5bfb\u5740\u7a7a\u95f4\u4e3a 4GB\uff0c\u5176\u4e2d\u6700\u9ad8 1GB\uff08\u4ece 0xC0000000 \u5230 0xFFFFFFFF\uff09\u4e13\u4f9b\u5185\u6838\u4f7f\u7528\uff0c\u79f0\u4e3a\u5185\u6838\u7a7a\u95f4\uff1b\u8f83\u4f4e\u7684 3GB\uff08\u4ece 0x00000000 \u5230 0xBFFFFFFF\uff09\u5206\u914d\u7ed9\u7528\u6237\u8fdb\u7a0b\uff0c\u79f0\u4e3a\u7528\u6237\u7a7a\u95f4\u3002\u8fd9\u79cd\u5206\u9694\u786e\u4fdd\u7528\u6237\u8fdb\u7a0b\u65e0\u6cd5\u76f4\u63a5\u8bbf\u95ee\u5185\u6838\u8d44\u6e90\uff0c\u4ece\u800c\u63d0\u9ad8\u7cfb\u7edf\u7684\u5b89\u5168\u6027\u548c\u7a33\u5b9a\u6027\u3002<\/p>\n

\u8fdb\u7a0b\u5207\u6362<\/h3>\n

\u8fdb\u7a0b\u5207\u6362\u662f\u6307\u5185\u6838\u6682\u505c\u4e00\u4e2a\u6b63\u5728\u8fd0\u884c\u7684\u8fdb\u7a0b\uff0c\u4ee5\u6062\u590d\u53e6\u4e00\u4e2a\u8fdb\u7a0b\u7684\u6267\u884c\u3002\u6b64\u8fc7\u7a0b\u5305\u62ec\uff1a<\/p>\n

    \n
  1. \u4fdd\u5b58\u5f53\u524d\u8fdb\u7a0b\u7684\u4e0a\u4e0b\u6587\uff08\u5982\u7a0b\u5e8f\u8ba1\u6570\u5668\u548c\u5bc4\u5b58\u5668\uff09\u3002<\/li>\n
  2. \u66f4\u65b0\u8fdb\u7a0b\u63a7\u5236\u5757\uff08PCB\uff09\u4fe1\u606f\u3002<\/li>\n
  3. \u5c06\u8fdb\u7a0b\u7684 PCB \u79fb\u5165\u76f8\u5e94\u961f\u5217\uff08\u5982\u5c31\u7eea\u961f\u5217\u6216\u963b\u585e\u961f\u5217\uff09\u3002<\/li>\n
  4. \u9009\u62e9\u53e6\u4e00\u4e2a\u8fdb\u7a0b\u6267\u884c\u5e76\u66f4\u65b0\u5176 PCB\u3002<\/li>\n
  5. \u66f4\u65b0\u5185\u5b58\u7ba1\u7406\u6570\u636e\u7ed3\u6784\u3002<\/li>\n
  6. \u6062\u590d\u65b0\u8fdb\u7a0b\u7684\u4e0a\u4e0b\u6587\u3002<\/li>\n<\/ol>\n

    \u6b64\u8fc7\u7a0b\u8d44\u6e90\u6d88\u8017\u8f83\u5927\uff0c\u56e0\u6b64\u9ad8\u6548\u7684 I\/O \u5904\u7406\u5bf9\u6027\u80fd\u81f3\u5173\u91cd\u8981\u3002<\/p>\n

    \u8fdb\u7a0b\u963b\u585e<\/h3>\n

    \u5f53\u8fdb\u7a0b\u56e0\u7b49\u5f85\u67d0\u4e9b\u4e8b\u4ef6\uff08\u5982 I\/O \u5b8c\u6210\u6216\u8d44\u6e90\u53ef\u7528\uff09\u800c\u65e0\u6cd5\u7ee7\u7eed\u6267\u884c\u65f6\uff0c\u4f1a\u8fdb\u5165\u963b\u585e\u72b6\u6001<\/strong>\u3002\u963b\u585e\u662f\u8fdb\u7a0b\u7684\u4e3b\u52a8\u884c\u4e3a\uff0c\u963b\u585e\u7684\u8fdb\u7a0b\u4e0d\u5360\u7528 CPU \u8d44\u6e90\uff0c\u5141\u8bb8\u5185\u6838\u5c06 CPU \u65f6\u95f4\u5206\u914d\u7ed9\u5176\u4ed6\u4efb\u52a1\u3002<\/p>\n

    \u6587\u4ef6\u63cf\u8ff0\u7b26<\/h3>\n

    \u6587\u4ef6\u63cf\u8ff0\u7b26<\/strong>\uff08fd\uff09\u662f\u5185\u6838\u7528\u6765\u5f15\u7528\u8fdb\u7a0b\u4e2d\u6253\u5f00\u7684\u6587\u4ef6\u6216\u5957\u63a5\u5b57\u7684\u975e\u8d1f\u6574\u6570\u3002\u5b83\u662f\u8fdb\u7a0b\u6587\u4ef6\u63cf\u8ff0\u7b26\u8868\u7684\u7d22\u5f15\uff0c\u662f Unix \u7c7b\u7cfb\u7edf\uff08\u5982 Linux\uff09\u4e2d\u7684\u6838\u5fc3\u6982\u5ff5\u3002<\/p>\n

    \u7f13\u5b58 I\/O<\/h3>\n

    Linux \u4e2d\u5927\u591a\u6570 I\/O \u64cd\u4f5c\u91c7\u7528\u7f13\u5b58 I\/O<\/strong>\uff0c\u6570\u636e\u9996\u5148\u88ab\u590d\u5236\u5230\u5185\u6838\u7684\u9875\u9762\u7f13\u5b58\u4e2d\uff0c\u7136\u540e\u624d\u4f20\u8f93\u5230\u7528\u6237\u8fdb\u7a0b\u7684\u5185\u5b58\u4e2d\u3002\u867d\u7136\u8fd9\u51cf\u5c11\u4e86\u76f4\u63a5\u78c1\u76d8\u8bbf\u95ee\uff0c\u4f46\u7531\u4e8e\u5185\u6838\u548c\u7528\u6237\u7a7a\u95f4\u4e4b\u95f4\u7684\u591a\u6b21\u6570\u636e\u590d\u5236\uff0c\u4f1a\u5e26\u6765\u6027\u80fd\u5f00\u9500\u3002<\/p>\n

    Linux I\/O \u6a21\u578b<\/h2>\n

    Linux \u652f\u6301\u591a\u79cd\u7f51\u7edc I\/O \u6a21\u578b\uff0c\u6bcf\u79cd\u6a21\u578b\u90fd\u6709\u5176\u72ec\u7279\u7279\u6027\u3002I\/O \u64cd\u4f5c\u901a\u5e38\u5305\u62ec\u4e24\u4e2a\u9636\u6bb5\uff1a<\/p>\n

      \n
    1. \u7b49\u5f85\u6570\u636e\u51c6\u5907<\/strong>\uff1a\u5185\u6838\u51c6\u5907\u6570\u636e\uff08\u4f8b\u5982\uff0c\u63a5\u6536\u5b8c\u6574\u7684\u7f51\u7edc\u6570\u636e\u5305\uff09\u3002<\/li>\n
    2. \u5c06\u6570\u636e\u590d\u5236\u5230\u8fdb\u7a0b<\/strong>\uff1a\u5c06\u6570\u636e\u4ece\u5185\u6838\u4f20\u8f93\u5230\u7528\u6237\u8fdb\u7a0b\u7684\u5185\u5b58\u3002<\/li>\n<\/ol>\n

      \u4e3b\u8981\u7684 I\/O \u6a21\u578b\u5305\u62ec\uff1a<\/p>\n

      \u963b\u585e I\/O<\/h3>\n

      \u5728\u963b\u585e I\/O<\/strong>\u6a21\u578b\u4e2d\uff0c\u8c03\u7528\u5982 recvfrom \u7684\u7cfb\u7edf\u8c03\u7528\u4f1a\u4f7f\u8fdb\u7a0b\u963b\u585e\uff0c\u76f4\u5230\u6570\u636e\u51c6\u5907\u597d\u5e76\u590d\u5236\u5230\u7528\u6237\u7a7a\u95f4\u3002\u6b64\u6a21\u578b\u7b80\u5355\uff0c\u4f46\u5bf9\u4e8e\u5904\u7406\u591a\u4e2a\u8fde\u63a5\u6548\u7387\u8f83\u4f4e\uff0c\u56e0\u4e3a\u8fdb\u7a0b\u5728\u7b49\u5f85\u671f\u95f4\u65e0\u6cd5\u6267\u884c\u5176\u4ed6\u4efb\u52a1\u3002<\/p>\n

      \u975e\u963b\u585e I\/O<\/h3>\n

      \u975e\u963b\u585e I\/O<\/strong>\u5141\u8bb8\u8fdb\u7a0b\u53d1\u8d77\u8bfb\u64cd\u4f5c\u5e76\u7acb\u5373\u83b7\u53d6\u7ed3\u679c\u3002\u5982\u679c\u6570\u636e\u672a\u51c6\u5907\u597d\uff0c\u5185\u6838\u4f1a\u8fd4\u56de\u9519\u8bef\uff08\u5982 EAGAIN\uff09\uff0c\u8fdb\u7a0b\u9700\u7a0d\u540e\u91cd\u8bd5\u3002\u8fd9\u8981\u6c42\u8fdb\u7a0b\u4e3b\u52a8\u8f6e\u8be2\u5185\u6838\uff0c\u53ef\u80fd\u4f1a\u6d88\u8017\u8f83\u591a CPU \u8d44\u6e90\u3002<\/p>\n

      I\/O \u591a\u8def\u590d\u7528<\/h3>\n

      I\/O \u591a\u8def\u590d\u7528<\/strong>\u4f7f\u5355\u4e2a\u8fdb\u7a0b\u80fd\u591f\u76d1\u63a7\u591a\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\u7684\u5c31\u7eea\u72b6\u6001\u3002select\u3001poll \u548c epoll \u90fd\u5c5e\u4e8e\u6b64\u7c7b\u522b\u3002\u8fd9\u4e9b\u662f\u540c\u6b65 I\/O \u6a21\u578b\uff0c\u56e0\u4e3a\u8fdb\u7a0b\u5728\u6536\u5230\u5c31\u7eea\u901a\u77e5\u540e\u4ecd\u9700\u81ea\u884c\u6267\u884c\u8bfb\/\u5199\u64cd\u4f5c\u3002<\/p>\n

      \u5f02\u6b65 I\/O<\/h3>\n

      \u5728\u5f02\u6b65 I\/O<\/strong>\u6a21\u578b\u4e2d\uff0c\u8fdb\u7a0b\u53d1\u8d77 I\/O \u64cd\u4f5c\u540e\u53ef\u7acb\u5373\u6267\u884c\u5176\u4ed6\u4efb\u52a1\uff0c\u65e0\u9700\u7b49\u5f85\u3002\u5185\u6838\u5728\u64cd\u4f5c\uff08\u5305\u62ec\u6570\u636e\u590d\u5236\uff09\u5b8c\u6210\u540e\u901a\u8fc7\u4fe1\u53f7\u901a\u77e5\u8fdb\u7a0b\u3002\u6b64\u6a21\u578b\u5168\u7a0b\u975e\u963b\u585e\uff0c\u6548\u7387\u9ad8\uff0c\u4f46 Linux \u652f\u6301\u6709\u9650\u3002<\/p>\n

      I\/O \u6a21\u578b\u6bd4\u8f83<\/h3>\n
      \n
      \n
      <\/div>\n<\/div>\n\n\n\n\n\n\n\n\n
      \u6a21\u578b<\/strong><\/th>\n\u9636\u6bb5 1 \u662f\u5426\u963b\u585e<\/strong><\/th>\n\u9636\u6bb5 2 \u662f\u5426\u963b\u585e<\/strong><\/th>\n\u4e3b\u8981\u7279\u6027<\/strong><\/th>\n<\/tr>\n<\/thead>\n
      \u963b\u585e I\/O<\/td>\n\u662f<\/td>\n\u662f<\/td>\n\u7b80\u5355\uff0c\u4f46\u5904\u7406\u591a\u8fde\u63a5\u6548\u7387\u4f4e\u3002<\/td>\n<\/tr>\n
      \u975e\u963b\u585e I\/O<\/td>\n\u5426<\/td>\n\u662f<\/td>\n\u9700\u8981\u4e3b\u52a8\u8f6e\u8be2\uff0c\u9002\u5408\u4f4e\u5ef6\u8fdf\u5e94\u7528\u3002<\/td>\n<\/tr>\n
      I\/O \u591a\u8def\u590d\u7528<\/td>\n\u662f<\/td>\n\u662f<\/td>\n\u9002\u5408\u5904\u7406\u591a\u8fde\u63a5\uff0cepoll \u4f18\u4e8e select \u548c poll\u3002<\/td>\n<\/tr>\n
      \u5f02\u6b65 I\/O<\/td>\n\u5426<\/td>\n\u5426<\/td>\n\u5168\u7a0b\u975e\u963b\u585e\uff0c\u4f46 Linux \u652f\u6301\u6709\u9650\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

      \u6df1\u5165\u89e3\u6790 I\/O \u591a\u8def\u590d\u7528\uff1aselect\u3001poll \u548c epoll<\/h2>\n

      I\/O \u591a\u8def\u590d\u7528\u9002\u7528\u4e8e\u9700\u8981\u7ba1\u7406\u591a\u4e2a\u8fde\u63a5\u7684\u5e94\u7528\uff08\u5982 Web \u670d\u52a1\u5668\uff09\u3002\u4ee5\u4e0b\u6bd4\u8f83\u4e09\u79cd\u4e3b\u8981\u673a\u5236\uff1aselect\u3001poll \u548c epoll\u3002<\/p>\n

      select<\/h3>\n

      select \u51fd\u6570\u7528\u4e8e\u76d1\u63a7\u6587\u4ef6\u63cf\u8ff0\u7b26\u7684\u8bfb\u3001\u5199\u6216\u5f02\u5e38\u4e8b\u4ef6\uff1a<\/p>\n

      \n
      \n
      c<\/div>\n
      \n
      \n
      <\/div>\n<\/div>\n<\/div>\n
      <\/code><\/p>\n
      \n
      \n
      int select(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout);<\/div>\n<\/div>\n<\/div>\n<\/div>\n
      <\/div>\n
      <\/div>\n<\/div>\n<\/div>\n
        \n
      • \u4f18\u70b9<\/strong>\uff1a\n
          \n
        • \u8de8\u5e73\u53f0\u517c\u5bb9\u6027\u5f3a\u3002<\/li>\n
        • \u9002\u5408\u5c0f\u89c4\u6a21\u5e94\u7528\u7684\u7b80\u5355\u5b9e\u73b0\u3002<\/li>\n<\/ul>\n<\/li>\n
        • \u7f3a\u70b9<\/strong>\uff1a\n
            \n
          • \u9ed8\u8ba4\u9650\u5236\u4e3a 1024 \u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\uff08Linux \u4e0a\u53ef\u914d\u7f6e\uff09\u3002<\/li>\n
          • \u7ebf\u6027\u626b\u63cf\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u6548\u7387\u968f\u63cf\u8ff0\u7b26\u6570\u91cf\u589e\u52a0\u800c\u4e0b\u964d\u3002<\/li>\n
          • \u6bcf\u6b21\u8c03\u7528\u9700\u5728\u7528\u6237\u7a7a\u95f4\u548c\u5185\u6838\u7a7a\u95f4\u4e4b\u95f4\u590d\u5236\u6587\u4ef6\u63cf\u8ff0\u7b26\u96c6\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

            poll<\/h3>\n

            poll \u51fd\u6570\u4f7f\u7528 pollfd \u7ed3\u6784\u76d1\u63a7\u6587\u4ef6\u63cf\u8ff0\u7b26\uff1a<\/p>\n

            \n
            \n
            c<\/div>\n
            \n
            \n
            <\/div>\n<\/div>\n<\/div>\n
            <\/code><\/p>\n
            \n
            \n
            struct pollfd {<\/div>\n
            int fd; \/* \u6587\u4ef6\u63cf\u8ff0\u7b26 *\/<\/div>\n
            short events; \/* \u8bf7\u6c42\u76d1\u63a7\u7684\u4e8b\u4ef6 *\/<\/div>\n
            short revents; \/* \u8fd4\u56de\u7684\u4e8b\u4ef6 *\/<\/div>\n
            };<\/div>\n<\/div>\n<\/div>\n<\/div>\n
            <\/div>\n
            <\/div>\n<\/div>\n<\/div>\n
              \n
            • \u4f18\u70b9<\/strong>\uff1a\n
                \n
              • \u65e0\u56fa\u5b9a\u6587\u4ef6\u63cf\u8ff0\u7b26\u6570\u91cf\u9650\u5236\u3002<\/li>\n
              • \u5bf9\u4e8e\u5927\u578b\u63cf\u8ff0\u7b26\u96c6\u6bd4 select \u66f4\u9ad8\u6548\u3002<\/li>\n<\/ul>\n<\/li>\n
              • \u7f3a\u70b9<\/strong>\uff1a\n
                  \n
                • \u4ecd\u9700\u8f6e\u8be2\u6240\u6709\u63cf\u8ff0\u7b26\uff0c\u6027\u80fd\u968f\u6570\u91cf\u589e\u52a0\u7ebf\u6027\u4e0b\u964d\u3002<\/li>\n
                • \u4e0e select \u7c7b\u4f3c\uff0c\u9700\u590d\u5236\u63cf\u8ff0\u7b26\u6570\u636e\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

                  epoll<\/h3>\n

                  epoll \u662f Linux 2.6 \u5185\u6838\u5f15\u5165\u7684\u589e\u5f3a\u578b\u591a\u8def\u590d\u7528\u673a\u5236\uff0c\u4e13\u4e3a\u53ef\u6269\u5c55\u6027\u8bbe\u8ba1\uff1a<\/p>\n

                  \n
                  \n
                  c<\/div>\n
                  \n
                  \n
                  <\/div>\n<\/div>\n<\/div>\n
                  <\/code><\/p>\n
                  \n
                  \n
                  int epoll_create(int size);<\/div>\n
                  int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event);<\/div>\n
                  int epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout);<\/div>\n<\/div>\n<\/div>\n<\/div>\n
                  <\/div>\n
                  <\/div>\n<\/div>\n<\/div>\n
                    \n
                  • \u6838\u5fc3\u7279\u6027<\/strong>\uff1a\n
                      \n
                    • \u4f7f\u7528\u5355\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\u7ba1\u7406\u591a\u4e2a\u63cf\u8ff0\u7b26\uff0c\u51cf\u5c11\u590d\u5236\u5f00\u9500\u3002<\/li>\n
                    • \u91c7\u7528\u57fa\u4e8e\u56de\u8c03\u7684\u673a\u5236\uff0c\u65e0\u9700\u626b\u63cf\u6240\u6709\u63cf\u8ff0\u7b26\u3002<\/li>\n
                    • \u652f\u6301\u65e0\u9650\u6570\u91cf\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff08\u4ec5\u53d7\u7cfb\u7edf\u8d44\u6e90\u9650\u5236\uff0c\u5982 \/proc\/sys\/fs\/file-max\uff09\u3002<\/li>\n<\/ul>\n<\/li>\n
                    • \u64cd\u4f5c<\/strong>\uff1a\n
                        \n
                      1. epoll_create\uff1a\u521b\u5efa epoll \u5b9e\u4f8b\uff0c\u8fd4\u56de\u6587\u4ef6\u63cf\u8ff0\u7b26\u3002<\/li>\n
                      2. epoll_ctl\uff1a\u7ba1\u7406\u7279\u5b9a\u6587\u4ef6\u63cf\u8ff0\u7b26\u7684\u4e8b\u4ef6\uff08\u6dfb\u52a0\u3001\u4fee\u6539\u3001\u5220\u9664\uff09\u3002<\/li>\n
                      3. epoll_wait\uff1a\u7b49\u5f85\u76d1\u63a7\u63cf\u8ff0\u7b26\u7684\u4e8b\u4ef6\uff0c\u8fd4\u56de\u5c31\u7eea\u4e8b\u4ef6\u3002<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n

                        epoll \u6a21\u5f0f\uff1a\u6c34\u5e73\u89e6\u53d1 (LT) vs. \u8fb9\u7f18\u89e6\u53d1 (ET)<\/h3>\n
                          \n
                        • \u6c34\u5e73\u89e6\u53d1 (LT)<\/strong>\uff1a\n
                            \n
                          • \u9ed8\u8ba4\u6a21\u5f0f\uff1b\u53ea\u8981\u63cf\u8ff0\u7b26\u5c31\u7eea\uff0c\u5e94\u7528\u7a0b\u5e8f\u5c31\u4f1a\u6536\u5230\u901a\u77e5\u3002<\/li>\n
                          • \u652f\u6301\u963b\u585e\u548c\u975e\u963b\u585e\u5957\u63a5\u5b57\u3002<\/li>\n
                          • \u672a\u5904\u7406\u4e8b\u4ef6\u4f1a\u91cd\u590d\u901a\u77e5\u3002<\/li>\n<\/ul>\n<\/li>\n
                          • \u8fb9\u7f18\u89e6\u53d1 (ET)<\/strong>\uff1a\n
                              \n
                            • \u4ec5\u5728\u63cf\u8ff0\u7b26\u72b6\u6001\u53d8\u5316\u65f6\u901a\u77e5\uff08\u5982\u65b0\u6570\u636e\u5230\u8fbe\uff09\u3002<\/li>\n
                            • \u9700\u4f7f\u7528\u975e\u963b\u585e\u5957\u63a5\u5b57\u4ee5\u907f\u514d\u963b\u585e\u95ee\u9898\u3002<\/li>\n
                            • \u901a\u77e5\u6b21\u6570\u5c11\uff0c\u6548\u7387\u9ad8\uff0c\u4f46\u9700\u5c0f\u5fc3\u5904\u7406\u4ee5\u514d\u9057\u6f0f\u4e8b\u4ef6\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

                              \u793a\u4f8b\u573a\u666f<\/h3>\n

                              \u5047\u8bbe\u4e00\u4e2a\u670d\u52a1\u5668\u4ece\u7ba1\u9053\u8bfb\u53d6 2KB \u6570\u636e\uff1a<\/p>\n

                                \n
                              1. \u5c06\u7ba1\u9053\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\u6dfb\u52a0\u5230 epoll \u5b9e\u4f8b\u3002<\/li>\n
                              2. \u7ba1\u9053\u53e6\u4e00\u7aef\u5199\u5165 2KB \u6570\u636e\u3002<\/li>\n
                              3. epoll_wait \u901a\u77e5\u670d\u52a1\u5668\u63cf\u8ff0\u7b26\u5df2\u5c31\u7eea\u3002<\/li>\n
                              4. \u670d\u52a1\u5668\u8bfb\u53d6 1KB \u6570\u636e\u3002<\/li>\n
                              5. \u5728 LT \u6a21\u5f0f<\/strong>\u4e0b\uff0cepoll_wait \u7ee7\u7eed\u901a\u77e5\u5269\u4f59\u7684 1KB \u6570\u636e\u3002\u5728 ET \u6a21\u5f0f<\/strong>\u4e0b\uff0c\u9664\u975e\u6709\u65b0\u6570\u636e\u5230\u8fbe\u6216\u63cf\u8ff0\u7b26\u72b6\u6001\u53d8\u5316\uff0c\u5426\u5219\u4e0d\u518d\u901a\u77e5\u3002<\/li>\n<\/ol>\n

                                epoll \u4ee3\u7801\u793a\u4f8b<\/h2>\n

                                \u4ee5\u4e0b\u662f\u4e00\u4e2a\u57fa\u4e8e epoll \u7684\u670d\u52a1\u5668\u5904\u7406\u5ba2\u6237\u7aef\u8fde\u63a5\u7684\u7b80\u5316\u793a\u4f8b\uff1a<\/p>\n

                                \n
                                \n
                                c<\/div>\n
                                \n
                                \n
                                <\/div>\n<\/div>\n<\/div>\n
                                <\/code><\/p>\n
                                \n
                                \n
                                #include <stdio.h><\/div>\n
                                #include <stdlib.h><\/div>\n
                                #include <string.h><\/div>\n
                                #include <sys\/epoll.h><\/div>\n
                                #include <sys\/socket.h><\/div>\n
                                #include <netinet\/in.h><\/div>\n
                                #include <arpa\/inet.h><\/div>\n
                                #include <unistd.h><\/div>\n
                                #include <errno.h><\/div>\n
                                <\/div>\n
                                #define IPADDRESS “127.0.0.1”<\/div>\n
                                #define PORT 8080<\/div>\n
                                #define MAXSIZE 1024<\/div>\n
                                #define EPOLLEVENTS 100<\/div>\n
                                <\/div>\n
                                void add_event(int epollfd, int fd, int state) {<\/div>\n
                                struct epoll_event ev;<\/div>\n
                                ev.events = state;<\/div>\n
                                ev.data.fd = fd;<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &ev);<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                void handle_accept(int epollfd, int listenfd) {<\/div>\n
                                struct sockaddr_in cliaddr;<\/div>\n
                                socklen_t cliaddrlen = sizeof(cliaddr);<\/div>\n
                                int clifd = accept(listenfd, (struct sockaddr*)&cliaddr, &cliaddrlen);<\/div>\n
                                if (clifd == -1) {<\/div>\n
                                perror(“\u63a5\u53d7\u9519\u8bef”);<\/div>\n
                                } else {<\/div>\n
                                printf(“\u65b0\u5ba2\u6237\u7aef: %s:%d\\n”, inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));<\/div>\n
                                add_event(epollfd, clifd, EPOLLIN);<\/div>\n
                                }<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                void do_read(int epollfd, int fd, char *buf) {<\/div>\n
                                int nread = read(fd, buf, MAXSIZE);<\/div>\n
                                if (nread == -1) {<\/div>\n
                                perror(“\u8bfb\u53d6\u9519\u8bef”);<\/div>\n
                                close(fd);<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL);<\/div>\n
                                } else if (nread == 0) {<\/div>\n
                                printf(“\u5ba2\u6237\u7aef\u5173\u95ed\\n”);<\/div>\n
                                close(fd);<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL);<\/div>\n
                                } else {<\/div>\n
                                printf(“\u8bfb\u53d6\u6570\u636e: %s\\n”, buf);<\/div>\n
                                struct epoll_event ev;<\/div>\n
                                ev.events = EPOLLOUT;<\/div>\n
                                ev.data.fd = fd;<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_MOD, fd, &ev);<\/div>\n
                                }<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                void do_write(int epollfd, int fd, char *buf) {<\/div>\n
                                int nwrite = write(fd, buf, strlen(buf));<\/div>\n
                                if (nwrite == -1) {<\/div>\n
                                perror(“\u5199\u5165\u9519\u8bef”);<\/div>\n
                                close(fd);<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_DEL, fd, NULL);<\/div>\n
                                } else {<\/div>\n
                                struct epoll_event ev;<\/div>\n
                                ev.events = EPOLLIN;<\/div>\n
                                ev.data.fd = fd;<\/div>\n
                                epoll_ctl(epollfd, EPOLL_CTL_MOD, fd, &ev);<\/div>\n
                                }<\/div>\n
                                memset(buf, 0, MAXSIZE);<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                void handle_events(int epollfd, struct epoll_event *events, int num, int listenfd, char *buf) {<\/div>\n
                                for (int i = 0; i < num; i++) {<\/div>\n
                                int fd = events[i].data.fd;<\/div>\n
                                if (fd == listenfd && (events[i].events & EPOLLIN)) {<\/div>\n
                                handle_accept(epollfd, listenfd);<\/div>\n
                                } else if (events[i].events & EPOLLIN) {<\/div>\n
                                do_read(epollfd, fd, buf);<\/div>\n
                                } else if (events[i].events & EPOLLOUT) {<\/div>\n
                                do_write(epollfd, fd, buf);<\/div>\n
                                }<\/div>\n
                                }<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                int main() {<\/div>\n
                                int listenfd = socket(AF_INET, SOCK_STREAM, 0);<\/div>\n
                                struct sockaddr_in servaddr;<\/div>\n
                                memset(&servaddr, 0, sizeof(servaddr));<\/div>\n
                                servaddr.sin_family = AF_INET;<\/div>\n
                                servaddr.sin_addr.s_addr = inet_addr(IPADDRESS);<\/div>\n
                                servaddr.sin_port = htons(PORT);<\/div>\n
                                bind(listenfd, (struct sockaddr*)&servaddr, sizeof(servaddr));<\/div>\n
                                listen(listenfd, 5);<\/div>\n
                                <\/div>\n
                                int epollfd = epoll_create(EPOLLEVENTS);<\/div>\n
                                add_event(epollfd, listenfd, EPOLLIN);<\/div>\n
                                struct epoll_event events[EPOLLEVENTS];<\/div>\n
                                char buf[MAXSIZE];<\/div>\n
                                <\/div>\n
                                while (1) {<\/div>\n
                                int ret = epoll_wait(epollfd, events, EPOLLEVENTS, -1);<\/div>\n
                                handle_events(epollfd, events, ret, listenfd, buf);<\/div>\n
                                }<\/div>\n
                                <\/div>\n
                                close(listenfd);<\/div>\n
                                close(epollfd);<\/div>\n
                                return 0;<\/div>\n
                                }<\/div>\n<\/div>\n<\/div>\n<\/div>\n
                                <\/div>\n
                                <\/div>\n<\/div>\n<\/div>\n

                                \u5173\u952e\u70b9<\/h3>\n
                                  \n
                                • \u521d\u59cb\u5316<\/strong>\uff1a\u521b\u5efa\u5957\u63a5\u5b57\uff0c\u7ed1\u5b9a\u5230 127.0.0.1:8080\uff0c\u5e76\u8bbe\u7f6e epoll \u5b9e\u4f8b\u3002<\/li>\n
                                • \u4e8b\u4ef6\u5faa\u73af<\/strong>\uff1a\u4f7f\u7528 epoll_wait \u76d1\u63a7\u4e8b\u4ef6\uff0c\u5e76\u901a\u8fc7 handle_events \u5904\u7406\u3002<\/li>\n
                                • \u4e8b\u4ef6\u5904\u7406<\/strong>\uff1a\u7ba1\u7406\u5ba2\u6237\u7aef\u8fde\u63a5\uff08handle_accept\uff09\u3001\u8bfb\u53d6\uff08do_read\uff09\u548c\u5199\u5165\uff08do_write\uff09\u3002<\/li>\n
                                • \u8d44\u6e90\u7ba1\u7406<\/strong>\uff1a\u6b63\u786e\u5173\u95ed\u6587\u4ef6\u63cf\u8ff0\u7b26\u4ee5\u9632\u6b62\u6cc4\u6f0f\u3002<\/li>\n<\/ul>\n

                                  epoll \u7684\u4f18\u52bf<\/h2>\n
                                    \n
                                  1. \u53ef\u6269\u5c55\u6027<\/strong>\uff1a\u652f\u6301\u5927\u91cf\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u4ec5\u53d7\u7cfb\u7edf\u8d44\u6e90\u9650\u5236\u3002<\/li>\n
                                  2. \u9ad8\u6548\u6027<\/strong>\uff1a\u4f7f\u7528\u56de\u8c03\u673a\u5236\uff0c\u907f\u514d select \u548c poll \u7684\u7ebf\u6027\u626b\u63cf\u3002<\/li>\n
                                  3. \u7075\u6d3b\u6027<\/strong>\uff1a\u652f\u6301 LT \u548c ET \u6a21\u5f0f\uff0c\u6ee1\u8db3\u4e0d\u540c\u5e94\u7528\u9700\u6c42\u3002<\/li>\n
                                  4. \u6027\u80fd<\/strong>\uff1a\u5728\u5904\u7406\u5927\u91cf\u7a7a\u95f2\u8fde\u63a5\u65f6\u8868\u73b0\u4f18\u5f02\uff0c\u4ec5\u5bf9\u5c31\u7eea\u63cf\u8ff0\u7b26\u89e6\u53d1\u56de\u8c03\u3002<\/li>\n<\/ol>\n

                                    \u7ed3\u8bba<\/h2>\n

                                    epoll \u6a21\u578b\u662f Linux \u9ad8\u6027\u80fd\u7f51\u7edc\u7f16\u7a0b\u7684\u57fa\u77f3\u3002\u5176\u53ef\u6269\u5c55\u6027\u3001\u6548\u7387\u548c\u7075\u6d3b\u6027\u4f7f\u5176\u6210\u4e3a\u5904\u7406\u6570\u5343\u8fde\u63a5\u7684\u5e94\u7528\u7a0b\u5e8f\uff08\u5982 Web \u670d\u52a1\u5668\u548c\u5b9e\u65f6\u7cfb\u7edf\uff09\u7684\u7406\u60f3\u9009\u62e9\u3002\u901a\u8fc7\u7406\u89e3\u548c\u5229\u7528 epoll \u7684 LT \u548c ET \u6a21\u5f0f\uff0c\u5f00\u53d1\u8005\u53ef\u4ee5\u6784\u5efa\u5065\u58ee\u3001\u9ad8\u6548\u7684\u7f51\u7edc\u5e94\u7528\u7a0b\u5e8f\uff0c\u6ee1\u8db3\u7279\u5b9a\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

                                    Linux epoll \u6a21\u578b\u662f\u4e00...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4924],"tags":[],"class_list":["post-208390","post","type-post","status-publish","format-standard","hentry","category-setup-tutorials"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208390","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=208390"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208390\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=208390"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=208390"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=208390"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}