{"id":600,"date":"2024-10-08T21:26:58","date_gmt":"2024-10-08T13:26:58","guid":{"rendered":"https:\/\/forelink.top\/?p=600"},"modified":"2024-10-08T21:27:00","modified_gmt":"2024-10-08T13:27:00","slug":"snowflake%e7%ae%97%e6%b3%95","status":"publish","type":"post","link":"https:\/\/forelink.top\/index.php\/2024\/10\/08\/snowflake%e7%ae%97%e6%b3%95\/","title":{"rendered":"SnowFlake\u7b97\u6cd5"},"content":{"rendered":"\n

\u7b80\u4ecb\uff1a<\/h1>\n\n\n\n

\u672c\u6587\u4ecb\u7ecd\u4e86snowflake\u7b97\u6cd5\uff0c\u4f18\u7f3a\u70b9\uff0c\u4ee5\u53ca\u5e94\u7528\u573a\u666f\u3002<\/p>\n\n\n\n

\u4f20\u7edf\u7684\u96c6\u4e2d\u5f0f\u7cfb\u7edf\u4e2d\uff0cID \u751f\u6210\u901a\u5e38\u7531\u4e00\u4e2a\u5355\u4e00\u7684\u670d\u52a1\u5668\u5b8c\u6210\uff0c\u5bfc\u81f4\u670d\u52a1\u5b58\u5728\u5355\u70b9\u6545\u969c\u7684\u95ee\u9898\u3002\n\u5f53\u7cfb\u7edf\u89c4\u6a21\u6269\u5927\u540e\uff0c\u5355\u4e00\u670d\u52a1\u5668\u53ef\u80fd\u65e0\u6cd5\u5904\u7406\u9ad8\u5e76\u53d1\u8bf7\u6c42\u3002\u800c\u5206\u5e03\u5f0f ID \u751f\u6210\u7b97\u6cd5\u65e8\u5728\u89e3\u51b3\u8fd9\u4e00\u95ee\u9898\uff0c\u5176\u4e2d\u6bcf\u4e2a\u8282\u70b9\u90fd\u80fd\u5e76\u884c\u5de5\u4f5c\u72ec\u7acb\u751f\u6210ID\uff0c\u662f\u53bb\u4e2d\u5fc3\u5316\u7684\u3002\n\u5206\u5e03\u5f0f\u7cfb\u7edf\u4e2d\uff0c\u6709\u9700\u8981\u4f7f\u7528\u5168\u5c40\u552f\u4e00 ID \u7684\u573a\u666f\u3002\nUUID ,Snowflake \u6216 Leaf \u7b97\u6cd5\u72ec\u7acb\u751f\u6210ID<\/p>\n\n\n\n

\u5176\u4e2d\u96ea\u82b1\u7b97\u6cd5\uff0c\u80fd\u6309\u7167\u65f6\u95f4\u751f\u6210\u6709\u5e8f\u7684ID\u3002<\/p>\n\n\n\n

\u96ea\u82b1\u7b97\u6cd5<\/h1>\n\n\n\n

Snowflake \u7b97\u6cd5\u662f Twitter\u5f00\u6e90\u7684\u5206\u5e03\u5f0f ID \u751f\u6210\u7b97\u6cd5\n\u7b97\u6cd5\u751f\u6210\u4e00\u4e2a64bit \u7684long\u578b\u6570\u503c\uff0c\u7ec4\u6210\u90e8\u5206\u5f15\u5165\u4e86\u65f6\u95f4\u6233\uff0c\u57fa\u672c\u4fdd\u6301\u4e86\u81ea\u589e\u3002<\/p>\n\n\n\n

\u4f18\u70b9<\/h2>\n\n\n\n
    \n
  1. \u9ad8\u6027\u80fd\u9ad8\u53ef\u7528\uff1a \u53ef\u5728\u5185\u5b58\u751f\u6210ID\uff0c\u4e0d\u4f9d\u8d56\u6570\u636e\u5e93\u3002<\/li>\n\n\n\n
  2. \u9ad8\u541e\u5410\uff1a\u96ea\u82b1\u7b97\u6cd5\u751f\u6210ID\u4e3b\u8981\u4f9d\u8d56\u7b80\u5355\u7684\u4f4d\u79fb\u64cd\u4f5c\uff0c\u901f\u5ea6\u6781\u5feb\u3002<\/li>\n\n\n\n
  3. \u6709\u5e8f\u6027\uff1a\u751f\u6210\u7684ID\u7684\u9ad8\u4f4d\u662f\u65f6\u95f4\u6233\uff0c\u53ef\u4ee5\u4f5c\u4e3a\u7d22\u5f15\u5b58\u5165\u7f13\u5b58\u4e2d\u3002<\/li>\n<\/ol>\n\n\n\n

    \u7f3a\u70b9<\/h2>\n\n\n\n
      \n
    1. \u5bf9\u673a\u5668\u65f6\u95f4\u4f9d\u8d56\u8f83\u5f3a\uff1a\u7cfb\u7edf\u65f6\u949f\u7684\u7cbe\u5ea6\u548c\u4e00\u81f4\u6027\u975e\u5e38\u5173\u952e\uff0c\u5982\u679c\u670d\u52a1\u5668\u65f6\u949f\u51fa\u73b0\u56de\u8c03\u6216\u4e0d\u540c\u6b65\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4ID \u91cd\u590d\u6216\u751f\u6210\u987a\u5e8f\u6df7\u4e71<\/li>\n\n\n\n
    2. \u6709\u65f6\u95f4\u9650\u5236\uff1a41\u4f4d\u65f6\u95f4\u6233\u53ea\u80fd\u4f7f\u7528\u7ea669\u5e74\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u65f6\u95f4\u53ef\u80fd\u9700\u8981\u624b\u52a8\u8c03\u6574\u7eaa\u5143\u65f6\u95f4\u3002<\/li>\n<\/ol>\n\n\n\n

      \u96ea\u82b1 ID \u7ed3\u6784<\/h1>\n\n\n\n

      \u9ed8\u8ba4\u7684\u96ea\u82b1\u7b97\u6cd5\u751f\u621064bit\u7684ID<\/p>\n\n\n\n

      | 1\u4f4d\u7b26\u53f7\u4f4d | 41\u4f4d\u65f6\u95f4\u6233 | 10\u4f4d\u673a\u5668\u6807\u8bc6 | 12\u4f4d\u5e8f\u5217\u53f7 |\n<\/code><\/pre>\n\n\n\n
      \u7b26\u53f7\u4f4d\uff1a\u6700\u9ad8\u4f4d\u662f\u7b26\u53f7\u4f4d\uff0c0\u8868\u793a\u6b63\uff0c1\u8868\u793a\u8d1f\uff0c\u8be5\u4f4d\u56fa\u5b9a\u4e3a0\uff0c\u7528\u4e8e\u4fdd\u6301\u751f\u6210\u7684ID\u4e3a\u6b63\u6570\u3002<\/p>\n\n\n\n
      \u65f6\u95f4\u6233\uff1a\u6beb\u79d2\u7ea7\u7684\u65f6\u95f4\u6233\uff0c\u7531\u4e00\u4e2a\u7eaa\u5143\u65f6\u95f4\uff08Epoch\uff09\u5f00\u59cb\u8ba1\u7b97\u5230\u5f53\u524d\u65f6\u95f4\u7684\u6beb\u79d2\u6570\u3002\u4ece\u5b9a\u4e49\u7684\u7eaa\u5143\u65f6\u95f4\u5f00\u59cb\uff0c\u6700\u591a\u652f\u630169\u5e74\u7684\u65f6\u95f4\u3002<\/p>\n\n\n\n
      \u673a\u5668\u6807\u8bc6\uff1a\u7528\u4e8e\u533a\u5206\u5206\u5e03\u5f0f\u7cfb\u7edf\u4e2d\u4e0d\u540c\u7684\u673a\u5668\u6216\u8005\u8282\u70b9\uff0c10\u4f4d\u53ef\u4ee5\u652f\u6301 2^10 = 1024<\/code>\u4e2a\u4e0d\u540c\u673a\u5668\u6216\u8282\u70b9\u3002\u901a\u5e38\uff0c10\u4f4d\u7684\u673a\u5668\u6807\u8bc6\u88ab\u5206\u4e3a\u4e24\u90e8\u5206\uff0c5\u4f4d\u7684\u6570\u636e\u4e2d\u5fc3ID \u548c 5\u4f4d\u673a\u5668ID\u3002\u8fd9\u6837\u53ef\u4ee5\u652f\u630132\u4e2a\u6570\u636e\u4e2d\u5fc3\u4e2d\u768432\u53f0\u673a\u5668\u3002<\/p>\n\n\n\n
      \u5e8f\u5217\u53f7\uff1a\u7528\u4e8e\u5728\u540c\u4e00\u6beb\u79d2\u4e2d\u751f\u6210\u591a\u4e2aID\uff0c\u907f\u514d\u65f6\u95f4\u6233\u51fa\u73b0\u51b2\u7a81\u300212\u4f4d\u53ef\u4ee5\u652f\u6301\u6bcf\u53f0\u673a\u5668\u6bcf\u6beb\u79d2\u4e2d\u751f\u6210 2^12 = 4096<\/code>\u4e2a\u552f\u4e00ID\u3002\uff08\u5f53\u540c\u4e00\u53f0\u673a\u5668\u5728\u540c\u4e00\u6beb\u79d2\u4e2d\u751f\u6210\u7684ID\u8d85\u8fc74096\u4e2a\uff0c\u673a\u5668\u4f1a\u7b49\u5f85\u4e0b\u4e00\u6beb\u79d2\u7ee7\u7eed\u751f\u6210\u65b0\u7684ID\u3002<\/p>\n\n\n\n
      \u96ea\u82b1ID\u7684\u957f\u5ea6\u662f\u53ef\u4ee5\u81ea\u884c\u914d\u7f6e\u7684\uff0c\u53ef\u4ee5\u6839\u636e\u5177\u4f53\u573a\u666f\u8fdb\u884c\u8bbe\u8ba1\u3002\n\u5e0c\u671b\u670d\u52a1\u8fd0\u884c\u66f4\u4e45\uff0c\u53ef\u4ee5\u589e\u52a0\u65f6\u95f4\u6233\u7684\u4f4d\u6570\u3002\n\u60f3\u8981\u652f\u6301\u66f4\u591a\u8282\u70b9\uff0c\u589e\u52a0\u6807\u8bc6\u4f4d\u957f\u5ea6\u3002\n\u9ad8\u5e76\u53d1\u573a\u666f\uff0c\u589e\u52a0\u5e8f\u5217\u53f7\u4f4d\u6570\u3002<\/p>\n\n\n\n
      \u96ea\u82b1ID\u9002\u7528\u573a\u666f<\/h1>\n\n\n\n
      \u56e0\u4e3a\u96ea\u82b1\u7b97\u6cd5\u6709\u5e8f\u81ea\u589e\uff0c\u5728MYSQL\u4e2d B+\u6811 \u7d22\u5f15\u53ef\u4ee5\u9ad8\u6027\u80fd\u63d2\u5165\uff0c\u6240\u4ee5\u5728\u65e5\u5e38\u4f7f\u7528\u4e2d\uff0c\u96ea\u82b1\u7b97\u6cd5\u66f4\u591a\u662f\u88ab\u5e94\u7528\u5728\u6570\u636e\u5e93\u7684\u4e3b\u952e ID \u548c\u4e1a\u52a1\u5173\u8054\u4e3b\u952e\n\u4e14\u96ea\u82b1ID\u6bcf\u79d2\u80fd\u751f\u6210 4096 * 1000 = 409w<\/code> \u4e2aID\uff0c\u9002\u7528\u4e8e\u9ad8\u5e76\u53d1\u573a\u666f<\/p>\n\n\n\n
      \u96ea\u82b1ID\u5e38\u89c1\u95ee\u9898<\/h1>\n\n\n\n
      \u751f\u6210ID\u91cd\u590d\u95ee\u9898<\/h2>\n\n\n\n
        \n
      1. \u670d\u52a1\u5668\u901a\u8fc7\u96c6\u7fa4\u7684\u65b9\u5f0f\u90e8\u7f72\uff0c\u5176\u4e2d\u90e8\u5206\u673a\u5668\u6807\u8bc6\u4f4d\u4e00\u81f4<\/li>\n\n\n\n
      2. \u4e1a\u52a1\u5b58\u5728\u4e00\u5b9a\u7684\u5e76\u53d1\u91cf\uff0c\u6ca1\u6709\u5e76\u53d1\u91cf\u65e0\u6cd5\u89e6\u53d1\u95ee\u9898<\/li>\n\n\n\n
      3. \u540c\u4e00\u6beb\u79d2\u4e0b\u751f\u6210<\/li>\n<\/ol>\n\n\n\n
        \u6807\u8bc6\u4f4d\u91cd\u590d\u5b9a\u4e49<\/h3>\n\n\n\n
        \u5f00\u6e90\u6846\u67b6\u4e2d\u5982MyBatis\u548cHutool\u4f7f\u7528\u96ea\u82b1\u7b97\u6cd5\uff0c\u90fd\u5b9e\u73b0\u4e86\u4e0d\u91cd\u590d\u6807\u8bc6\u4f4d\u7684\u6784\u9020\u65b9\u6cd5\u3002\nMyBatis-Plus v3.4.2 \u96ea\u82b1\u7b97\u6cd5\u5b9e\u73b0\u7c7b Sequence\uff0c\u63d0\u4f9b\u4e86\u4e24\u79cd\u6784\u9020\u65b9\u6cd5\uff1a\n    \u65e0\u53c2\u6784\u9020 -> \u81ea\u52a8\u751f\u6210dataCenterId \u548c workerId\n    \u6709\u53c2\u6784\u9020 -> \u521b\u5efaSequence\u65f6\u660e\u786e\u6307\u5b9a\u6807\u8bc6\u4f4d<\/p>\n\n\n\n
        Sequence\u9ed8\u8ba4\u7684\u65e0\u53c2\u6784\u9020\uff0c\u751f\u6210\u4e86dataCenterId\u548cIworkerd<\/p>\n\n\n\n
        public static long getDataCenterId(long maxDatacenterId) {\n    long id = 1L;\n    final byte[] mac = NetUtil.getLocalHardwareAddress();\n    if (null != mac) {\n        id = ((0x000000FF & (long) mac[mac.length - 2])\n                | (0x0000FF00 & (((long) mac[mac.length - 1]) << 8))) >> 6;\n        id = id % (maxDatacenterId + 1);\n    }\n\n    return id;\n}\n<\/code><\/pre>\n\n\n\n
        DatacenterId\u7684\u53d6\u503c\u4e0e\u8bbe\u5907Mac\u5730\u5740\u6709\u5173<\/p>\n\n\n\n
        public static long getWorkerId(long datacenterId, long maxWorkerId) {\n    final StringBuilder mpid = new StringBuilder();\n    mpid.append(datacenterId);\n    try {\n    \/\/ \u83b7\u53d6\u8fdb\u7a0bPID\n        mpid.append(RuntimeUtil.getPid());\n    } catch (UtilException igonre) {\n        \/\/ignore\n    }\n    return (mpid.toString().hashCode() & 0xffff) % (maxWorkerId + 1);\n}\n<\/code><\/pre>\n\n\n\n
        WorkerId\u662fMAC+PID\u7684hashcode\uff0c\u83b7\u53d616\u4e2a\u4f4e\u4f4d<\/p>\n\n\n\n
        \u6807\u8bc6\u7b26\u5206\u914d<\/h3>\n\n\n\n
        \u4f9d\u8d56MAC\u5730\u5740\u548c\u8fdb\u7a0bPID\u7684\u6807\u8bc6\u7b26\u4ecd\u7136\u6709\u5c0f\u51e0\u7387\u91cd\u590d\uff0c\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u53ef\u4ee5\u7528 \u9884\u5206\u914d\u548c\u52a8\u6001\u5206\u914d<\/strong> \u7684\u65b9\u6cd5\u3002<\/p>\n\n\n\n
        \u9884\u5206\u914d<\/strong> \u662f\u5728\u5e94\u7528\u4e0a\u7ebf\u524d\uff0c\u7edf\u8ba1\u5f53\u524d\u670d\u52a1\u7684\u8282\u70b9\u6570\uff0c\u4eba\u5de5\u7684\u7533\u8bf7\u6807\u8bc6\u4f4d\u3002\u4f46\u662f\u65e0\u6cd5\u89e3\u51b3\u670d\u52a1\u8282\u70b9\u52a8\u6001\u6269\u5c55\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n
        \u52a8\u6001\u5206\u914d<\/strong> \u5c06\u6807\u8bc6\u4f4d\u5b58\u653e\u5728Redis\u3001Zookeeper\u3001MySQL\u7b49\u4e2d\u95f4\u4ef6\uff0c\u5728\u670d\u52a1\u542f\u52a8\u65f6\u8bf7\u6c42\u6807\u8bc6\u4f4d\u3002\n\u4f46\u8981\u6ce8\u610f\u751f\u6210\u7684ID\u662f \u670d\u52a1\u5185\u552f\u4e00<\/strong> \u8fd8\u662f \u5168\u5c40\u552f\u4e00<\/strong> \n\u5168\u5c40\u552f\u4e00<\/strong> \u53ef\u80fd\u4f1a\u5bfc\u81f4\u5355\u70b9\u6545\u969c\u95ee\u9898\u3002<\/p>\n\n\n\n
        \u5e38\u89c1\u7684\u5b9e\u73b0\u662f Redis + Lua \u811a\u672c\uff0c\u5728\u5e94\u7528\u542f\u52a8\u65f6\uff0c\u901a\u8fc7Lua\u811a\u672c\u83b7\u53d6\u6807\u8bc6\u4f4d\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
        \u7b80\u4ecb\uff1a \u672c\u6587\u4ecb\u7ecd\u4e86snowflake\u7b97\u6cd5\uff0c\u4f18\u7f3a\u70b9\uff0c\u4ee5\u53ca\u5e94\u7528\u573a\u666f\u3002 \u4f20\u7edf\u7684\u96c6\u4e2d\u5f0f\u7cfb\u7edf\u4e2d\uff0cID \u751f\u6210\u901a\u5e38\u7531\u4e00\u4e2a\u5355\u4e00 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","footnotes":""},"categories":[53,17],"tags":[],"class_list":["post-600","post","type-post","status-publish","format-standard","hentry","category-53","category-17"],"_links":{"self":[{"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/posts\/600","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/comments?post=600"}],"version-history":[{"count":1,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/posts\/600\/revisions"}],"predecessor-version":[{"id":601,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/posts\/600\/revisions\/601"}],"wp:attachment":[{"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/media?parent=600"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/categories?post=600"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forelink.top\/index.php\/wp-json\/wp\/v2\/tags?post=600"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}