{"id":1737,"date":"2023-03-26T20:05:41","date_gmt":"2023-03-26T12:05:41","guid":{"rendered":"https:\/\/www.appblog.cn\/?p=1737"},"modified":"2023-04-23T21:31:05","modified_gmt":"2023-04-23T13:31:05","slug":"deep-analysis-of-leaf-meituan-distributed-unique-id-scheme","status":"publish","type":"post","link":"https:\/\/www.appblog.cn\/index.php\/2023\/03\/26\/deep-analysis-of-leaf-meituan-distributed-unique-id-scheme\/","title":{"rendered":"Leaf – \u7f8e\u56e2\u7684\u5206\u5e03\u5f0f\u552f\u4e00ID\u65b9\u6848\u6df1\u5165\u5256\u6790"},"content":{"rendered":"

\u7f8e\u56e2\u70b9\u8bc4\u5f00\u6e90\u5206\u5e03\u5f0fID\u751f\u6210\u7cfb\u7edfLeaf\uff1ahttps:\/\/github.com\/Meituan-Dianping\/Leaf<\/a><\/p>\n

\u4e3a\u4ec0\u4e48\u53ebleaf\uff1f\u56e0\u4e3a\u5929\u5e95\u4e0b\u6ca1\u6709\u4e24\u7247\u5b8c\u5168\u4e00\u6837\u7684\u6811\u53f6\uff08\u5fb7\u56fd\u54f2\u5b66\u5bb6\u3001\u6570\u5b66\u5bb6\u83b1\u5e03\u5c3c\u8328\uff1aThere are no two identical leaves in the world\uff09\uff0c\u610f\u5473\u7740\u6bcf\u6b21\u901a\u8fc7leaf\u83b7\u53d6\u7684ID\u80af\u5b9a\u662f\u552f\u4e00\u7684\u3002<\/p>\n

<\/p>\n

\u672c\u6587\u8f6c\u8f7d\u81f3\uff1ahttps:\/\/www.jianshu.com\/p\/bd6b00e5f5ac<\/a><\/p>\n

Leaf\u57fa\u672c\u4f7f\u7528<\/h2>\n

\u914d\u7f6e<\/h3>\n

Leaf\u662f\u57fa\u4e8eSpring Boot\u3001\u4ee5HTTP\u534f\u8bae\u7684\u65b9\u5f0f\u63d0\u4f9b\u83b7\u53d6\u5206\u5e03\u5f0f\u552f\u4e00ID\u7684\u670d\u52a1\u3002\u603b\u8ba1\u6709\u4e24\u79cd\u6a21\u5f0f\uff1aSnowflake<\/code>\u548cSegment<\/code>\u3002\u6211\u4eec\u901a\u8fc7\u5b83\u7684\u6838\u5fc3\u914d\u7f6e\u6587\u4ef6leaf.properties<\/code>\u53ef\u77e5\uff1a<\/p>\n

leaf.name=leaf\n# segment\u6a21\u5f0f\u5f00\u5173\uff0c\u8fd9\u79cd\u6a21\u5f0f\u4f9d\u8d56\u6570\u636e\u5e93\nleaf.segment.enable=true\nleaf.jdbc.url=jdbc:mysql:\/\/localhost:3306\/leaf\nleaf.jdbc.username=leaf\nleaf.jdbc.password=leaf\n\n# snowflake\u6a21\u5f0f\uff0c\u8fd9\u79cd\u6a21\u5f0f\u4f9d\u8d56zookeeper\nleaf.snowflake.enable=true\nleaf.snowflake.zk.address=127.0.0.1:2181\nleaf.snowflake.port=8686<\/code><\/pre>\n
DDL & DML<\/h3>\n
\u9996\u5148\u521b\u5efa\u8868leaf_alloc<\/code>\uff08DDL\u8bed\u53e5\u5728GitHub\u9996\u9875\u53ef\u4ee5\u627e\u5230\uff09\uff1a<\/p>\n
CREATE DATABASE leaf\nCREATE TABLE `leaf_alloc` (\n  `id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,\n  `biz_tag` varchar(128)  NOT NULL DEFAULT '',\n  `max_id` bigint(20) NOT NULL DEFAULT '1',\n  `step` int(11) NOT NULL,\n  `description` varchar(256)  DEFAULT NULL,\n  `update_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,\n  PRIMARY KEY (`id`),\n  UNIQUE KEY (`biz_tag`)\n) ENGINE=InnoDB;<\/code><\/pre>\n
\u7136\u540e\u9700\u8981\u63d2\u5165\u51e0\u6761\u521d\u59cb\u5316\u6570\u636e\uff0c\u5047\u8bbe\u652f\u4ed8\u670d\u52a1\u548c\u8d26\u6237\u670d\u52a1\u9700\u8981\u8c03\u7528leaf\u83b7\u53d6\u552f\u4e00ID\uff0c\u90a3\u4e48\u521d\u59cb\u5316\u6570\u636e\u7684SQL\u5982\u4e0b\uff1a<\/p>\n
insert into leaf_alloc(biz_tag, max_id, step, description) values('pay', 1, 2000, 'leaf'),('account', 1, 2000, 'leaf');<\/code><\/pre>\n
\u542f\u52a8<\/h3>\n
\u7531\u4e8eleaf\u57fa\u4e8eSpring Boot\u5f00\u53d1\uff0c\u6240\u4ee5\u542f\u52a8\u975e\u5e38\u7b80\u5355\uff0c\u8fd0\u884ccom.sankuai.inf.leaf.server.LeafServerApplication<\/code>\u5373\u53ef\u3002<\/p>\n
\u8bbf\u95ee<\/h3>\n
Snowflake<\/code>\u548cSegment<\/code>\u4e24\u79cd\u83b7\u53d6\u552f\u4e00ID\u7684\u6a21\u5f0f\u7684\u8bbf\u95ee\u65b9\u5f0f\u5982\u4e0b\uff1a<\/p>\n
# Segment\u6a21\u5f0f\u83b7\u53d6\u552f\u4e00ID\nhttp:\/\/localhost:8080\/api\/segment\/get\/pay\nhttp:\/\/localhost:8080\/api\/segment\/get\/account\n# Snowflake\u6a21\u5f0f\u83b7\u53d6\u552f\u4e00ID\nhttp:\/\/localhost:8080\/api\/snowflake\/get\/pay\nhttp:\/\/localhost:8080\/api\/snowflake\/get\/account<\/code><\/pre>\n
\u76d1\u63a7<\/h3>\n
Leaf\u63d0\u4f9b\u4e86\u975e\u5e38\u7b80\u5355\u7684\u76d1\u63a7\u9875\u9762\uff0c\u80fd\u591f\u8ba9\u7528\u6237\u770b\u5230Segment\u6a21\u5f0f\u4e0b\u6709\u54ea\u4e9b\u670d\u52a1\uff0c\u4ee5\u53ca\u8fd9\u4e9b\u670d\u52a1\u5f53\u524d\u83b7\u53d6\u552f\u4e00ID\u7684\u4f4d\u7f6e\u3002\u8fd9\u4e2a\u76d1\u63a7\u9875\u9762\u4e8b\u5b9e\u4e0a\u5c31\u662f\u53ef\u89c6\u5316\u672c\u5730\u5185\u5b58\u4e2d\u7684\u6570\u636e\uff0c\u6240\u4ee5\u4e00\u5b9a\u8981\u5728Leaf\u542f\u52a8\u540e\u83b7\u53d6\u8fc7\u81f3\u5c11\u4e00\u6b21\u552f\u4e00ID\uff0c\u5176\u5bf9\u5e94\u7684\u6570\u636e\u624d\u80fd\u6b63\u5e38\u5c55\u793a\uff0c\u5426\u5219\u90fd\u662f0\u3002\u8bbf\u95ee\u5730\u5740\u662f http:\/\/localhost:8080\/cache<\/code>\uff0c\u8bbf\u95ee\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n
\"leaf-cache\u76d1\u63a7\"<\/p>\n
Leaf\u6df1\u5165\u5256\u6790<\/h2>\n
\u63a5\u4e0b\u6765\u5206\u522b\u5bf9Leaf\u63d0\u4f9b\u7684\u4e24\u79cd\u6a21\u5f0f\u8fdb\u884c\u6df1\u5165\u5256\u6790\u3002<\/p>\n
Segment\u6a21\u5f0f<\/h3>\n
\u524d\u9762\u5df2\u7ecf\u63d0\u5230\uff0cSegment\u6a21\u5f0f\u4f9d\u8d56\u6570\u636e\u5e93\u3002\u8ba4\u8bc6Leaf\u7684Segment\u6a21\u5f0f\u4e4b\u524d\uff0c\u6211\u4eec\u5047\u8bbe\u5728\u4e0d\u8003\u8651\u5e76\u53d1\u80fd\u529b\u7684\u60c5\u51b5\u4e0b\u5982\u4f55\u901a\u8fc7\u6570\u636e\u5e93\u83b7\u53d6\u552f\u4e00ID\uff1a\u5229\u7528MySQL\u7684\u81ea\u589e\u4e3b\u952e<\/strong>\uff0c\u800c\u4e14MyBatis\u53ef\u4ee5\u83b7\u53d6\u6bcf\u6b21insert\u7684\u4e3b\u952eID\u3002\u8fd9\u79cd\u65b9\u6848\u7684\u4f18\u70b9<\/strong>\u5982\u4e0b\uff1a<\/p>\n
    \n
  • \u975e\u5e38\u7b80\u5355\uff0c\u5229\u7528\u73b0\u6709\u6570\u636e\u5e93\u7cfb\u7edf\u7684\u529f\u80fd\u5b9e\u73b0\uff0c\u6210\u672c\u5c0f\uff0c\u6709DBA\u4e13\u4e1a\u7ef4\u62a4<\/li>\n
  • ID\u53f7\u5355\u8c03\u81ea\u589e\uff0c\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e9b\u5bf9ID\u6709\u7279\u6b8a\u8981\u6c42\u7684\u4e1a\u52a1<\/li>\n<\/ul>\n
    \u7f3a\u70b9<\/strong>\u5982\u4e0b\uff1a<\/p>\n
      \n
    • \u5f3a\u4f9d\u8d56DB\uff0c\u5f53DB\u5f02\u5e38\u65f6\u6574\u4e2a\u7cfb\u7edf\u4e0d\u53ef\u7528\uff0c\u5c5e\u4e8e\u81f4\u547d\u95ee\u9898\u3002\u914d\u7f6e\u4e3b\u4ece\u590d\u5236\u53ef\u4ee5\u5c3d\u53ef\u80fd\u7684\u589e\u52a0\u53ef\u7528\u6027\uff0c\u4f46\u662f\u6570\u636e\u4e00\u81f4\u6027\u5728\u7279\u6b8a\u60c5\u51b5\u4e0b\u96be\u4ee5\u4fdd\u8bc1\u3002\u4e3b\u4ece\u5207\u6362\u65f6\u7684\u4e0d\u4e00\u81f4\u53ef\u80fd\u4f1a\u5bfc\u81f4\u91cd\u590d\u53d1\u53f7\u3002<\/li>\n
    • ID\u53d1\u53f7\u6027\u80fd\u74f6\u9888\u9650\u5236\u5728\u5355\u53f0MySQL\u7684\u8bfb\u5199\u6027\u80fd\u3002<\/li>\n<\/ul>\n
      Segment<\/code>\u6709\u201c\u6bb5\u201d\u7684\u610f\u601d\uff0cLeaf\u8fd9\u79cd\u6a21\u5f0f\u610f\u5473\u7740\u5e76\u4e0d\u662f\u6bcf\u6b21\u83b7\u53d6\u552f\u4e00ID\u90fd\u9700\u8981\u64cd\u4f5c\u6570\u636e\u5e93\u3002\u6240\u4ee5\uff0cSegment<\/code>\u6a21\u5f0f\u5c31\u662f\u5728\u524d\u9762\u63d0\u5230\u7684\u6570\u636e\u5e93\u65b9\u6848\u57fa\u7840\u4e4b\u4e0a\u8fdb\u884c\u4e86\u4f18\u5316\uff1a\u65e2\u7136\u6bcf\u6b21\u64cd\u4f5c\u6570\u636e\u5e93\u6027\u80fd\u6709\u95ee\u9898\uff0c\u90a3\u4e48\u6211\u5c31\u6bcf\u8fc7N\u6b21\u624d\u64cd\u4f5c\u4e00\u6b21\u6570\u636e\u5e93\u3002\u5728\u8fd9N\u6b21\u4ee5\u5185\u7684\u8bbf\u95ee\uff0c\u90fd\u53ea\u9700\u8981\u901a\u8fc7\u64cd\u4f5c\u672c\u5730\u7f13\u5b58\u83b7\u53d6\u3002\u5982\u6b64\u4e00\u6765\uff0c\u6027\u80fd\u5c31\u5f88\u9ad8\u4e86\u3002\u8fd9\u4e2aN\u503c\u8868\u793a\u7684\u8303\u56f4\u5c31\u662fSegment<\/code>\u7684\u610f\u601d\u3002<\/p>\n
      \u4e0d\u8fc7\u8fd8\u662f\u6709\u70b9\u7455\u75b5\uff0c\u56e0\u4e3a\u6bcf\u8fc7N\u6b21\u90fd\u8981\u64cd\u4f5c\u4e00\u6b21\u6570\u636e\u5e93<\/strong>\u3002\u5982\u679c\u6070\u597d\u5728\u8fd9\u4e2a\u65f6\u5019\u5e76\u53d1\u8f83\u9ad8\uff0c\u90a3\u4e48\u6570\u636e\u5e93\u64cd\u4f5c\u5c31\u4f1a\u963b\u585e\uff0c\u751a\u81f3\u51fa\u73b0\u8d85\u65f6\uff0c\u4ece\u800c\u5f62\u6210\u6027\u80fd\u6bdb\u523a\u751a\u81f3\u964d\u4f4eSLA\u3002\u600e\u4e48\u529e\uff1fLeaf\u7684\u505a\u6cd5\u662f\u5c06\u8fd9\u4e2a\u6b65\u9aa4\u63d0\u524d\u5e76\u5f02\u6b65\u5316<\/strong>\uff0cLeaf\u7684Segment<\/code>\u6a21\u5f0f\u7528\u4e00\u5f20\u56fe\u8868\u793a\u5982\u4e0b\uff1a<\/p>\n
      \"leaf<\/p>\n
      \u5982\u56fe\u6240\u793a\uff1a<\/p>\n
        \n
      • \u8bbe\u7f6estep\u4e3a1000\uff08\u53ef\u901a\u8fc7DML\u914d\u7f6e\uff09\uff1b<\/li>\n
      • \u5f53\u53d1\u53f7\u671f\u5df2\u7ecf\u5206\u53d1\u5230100\u7684\u65f6\u5019\uff08\u5373\u53d6\u4e86\u6b65\u957fstep\u768410%\uff09\uff0c\u5c31\u4f1a\u89e6\u53d1\u4e00\u4e2a\u5f02\u6b65\u64cd\u4f5c\u53bb\u521d\u59cb\u5316\u4e0b\u4e00\u4e2a\u53f7\u6bb5\uff1b<\/li>\n
      • \u5f531\uff5e1000\u7528\u5c3d\u5e76\u4e14\u5206\u914d\u52301100\u7684\u65f6\u5019\uff0c\u53c8\u4f1a\u89e6\u53d1\u5f02\u6b65\u64cd\u4f5c\u53bb\u521d\u59cb\u5316\u53c81\u4e2a\u53f7\u6bb5\uff082001\uff5e3000\uff09\uff0c\u4ee5\u6b64\u7c7b\u63a8\uff1b<\/li>\n<\/ul>\n
        \u901a\u8fc7\u8fd9\u79cd\u65b9\u6848\u8bbe\u8ba1\uff0c\u6bcf\u6b21\u83b7\u53d6\u552f\u4e00ID\u90fd\u53ea\u9700\u8981\u64cd\u4f5c\u5185\u5b58\u5373\u53ef\u3002\u81f3\u4e8e\u5bf9\u6570\u636e\u5e93\u7684\u64cd\u4f5c\uff0c\u5b8c\u5168\u5f02\u6b65\u5b8c\u6210\u3002<\/p>\n
        \u4e00\u4e9b\u7591\u95ee\u70b9<\/strong>\uff1a<\/p>\n
        \u8fd9\u79cd\u65b9\u6848\u662f\u5982\u4f55\u907f\u514d\u91cd\u542f\u540e\u5206\u914d\u91cd\u590d\u7684ID\u5462<\/strong>\uff1f\u6211\u4eec\u5047\u8bbe\u5df2\u7ecf\u5206\u914d\u52301122\uff0c\u8fd9\u4e2a1122\u53c8\u6ca1\u6709\u6301\u4e45\u5316\u5230\u4efb\u4f55\u4e00\u4e2a\u5730\u65b9\uff0c\u6570\u636e\u5e93\u4e2d\u53ea\u4fdd\u5b58\u4e86\uff08max_id=2001, step=1000\uff09\uff0c\u5982\u679c\u8fd9\u65f6\u5019Leaf\u5b95\u673a\u3002Leaf\u7684\u505a\u6cd5\u662f\u5728\u7b2c\u4e00\u6b21\u83b7\u53d6\u552f\u4e00ID\u7684\u65f6\u5019\uff0c\u4f1a\u9996\u5148\u66f4\u65b0\u6570\u636e\u5e93\u8df3\u5230\u4e0b\u4e00\u4e2a\u53f7\u6bb5\uff08max_id=3001, step=1000\uff09\uff0c\u90a3\u4e48\u8fd9\u65f6\u5019\u83b7\u53d6\u7684\u552f\u4e00ID\u5c31\u662f2001\uff0c\u81f3\u4e8e1123\uff5e2000\u4e4b\u524d\u7684ID\u5168\u90e8\u88ab\u629b\u5f03\uff0c\u4e0d\u4f1a\u88ab\u5206\u914d\u4e86\u3002<\/p>\n
        Segment\u6a21\u5f0f\u6709\u65f6\u949f\u56de\u62e8\u95ee\u9898\u5417<\/strong>\uff1f\u5f88\u660e\u663e\u6ca1\u6709\uff0c\u56e0\u4e3a\u901a\u8fc7\u8fd9\u79cd\u6a21\u5f0f\u83b7\u53d6\u7684ID\u6ca1\u6709\u4efb\u4f55\u65f6\u95f4\u5c5e\u6027\uff0c\u6240\u4ee5\u4e0d\u5b58\u5728\u65f6\u949f\u56de\u62e8\u95ee\u9898\u3002<\/p>\n
        \u65b0\u589e\u670d\u52a1\u9700\u8981\u591a\u4e45\u751f\u6548<\/strong>\uff1f\u5047\u8bbe\u6211\u4eec\u901a\u8fc7SQL\u8bed\u53e5\u63d2\u5165\u4e00\u4e2a\u8ba2\u5355\u670d\u52a1\uff0c\u90a3\u4e48\u8981\u8fc7\u591a\u4e45\u8ba2\u5355\u670d\u52a1\u624d\u80fd\u901a\u8fc7\u8bf7\u6c42\u5730\u5740http:\/\/localhost:8080\/api\/segment\/get\/order<\/code>\u5411Leaf\u83b7\u53d6\u552f\u4e00ID\u5462\uff1f<\/p>\n
        insert into leaf.leaf_alloc values('order', 1, 1000, 'leaf', now());<\/code><\/pre>\n
        \u7b54\u6848\u662f\u6700\u591a60s<\/strong>\uff0c\u56e0\u4e3aLeaf\u6709\u4e00\u4e2aschedule\u4efb\u52a1\uff0c\u95f4\u969460s\u5237\u65b0\u672c\u5730\u7f13\u5b58\u4e2d\u7684\u670d\u52a1\u4fe1\u606f\uff0c\u5047\u8bbe\u5237\u65b0\u524d\u53ea\u6709[pay\uff0caccount]\u4e24\u4e2a\u670d\u52a1\uff0c\u90a3\u4e48\u5237\u65b0\u540e\u5c31\u6709[pay\uff0caccount\uff0corder]\u4e09\u4e2a\u670d\u52a1\u3002\u6838\u5fc3\u6e90\u7801\u5982\u4e0b\uff1a<\/p>\n
        private void updateCacheFromDbAtEveryMinute() {\n    ScheduledExecutorService service = Executors.newSingleThreadScheduledExecutor(new ThreadFactory() {\n        @Override\n        public Thread newThread(Runnable r) {\n            Thread t = new Thread(r);\n            t.setName("check-idCache-thread");\n            t.setDaemon(true);\n            return t;\n        }\n    });\n    service.scheduleWithFixedDelay(new Runnable() {\n        @Override\n        public void run() {\n            updateCacheFromDb();\n        }\n    }, 60, 60, TimeUnit.SECONDS);\n}\n\nprivate void updateCacheFromDb() {\n    logger.info("update cache from db");\n    try {\n        List<String> dbTags = dao.getAllTags();\n        \/\/ \u8fd9\u91cc\u5c31\u4f1a\u66f4\u65b0\u672c\u5730\u7f13\u5b58\u4e2d\u7684\u63a5\u5165\u670d\u52a1\u5217\u8868\u4fe1\u606f\uff08\u5373leaf_alloc\u8868\u4e2d\u7684biz_tag\u5b57\u6bb5\uff09\n        ...\n    }\n    ...\n}<\/code><\/pre>\n
        Snowflake\u6a21\u5f0f<\/h2>\n
        Leaf\u7684Snowflake<\/code>\u6a21\u5f0f\uff0c\u987e\u540d\u601d\u4e49\uff0c\u6e90\u81ea\u4e8etwitter\u7684Snowflake\u7b97\u6cd5\uff0c\u517664\u4f4d\u6784\u6210\u5982\u4e0b\uff0cLeaf\u7684Snowflake<\/code>\u6a21\u5f0f\u4e0e\u539f\u751fSnowflake<\/code>\u6a21\u5f0f\u5b8c\u5168\u4e00\u81f4<\/strong>\uff0c\u90fd\u662f\u91c7\u75281+41+10+12<\/code>\u7684\u6a21\u5f0f\uff0c\u4e14\u4e0d\u53ef\u914d\u7f6e\uff0c\u9664\u975e\u4fee\u6539\u6e90\u7801\uff1a<\/p>\n
        \"snowflake<\/p>\n
        Leaf\u7684Snowflake<\/code>\u6a21\u5f0f\u6838\u5fc3\u6e90\u7801\u5728com.sankuai.inf.leaf.snowflake.SnowflakeIDGenImpl<\/code>\u4e2d\u3002\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u770b\u770b\u8be5\u6a21\u5f0f\u4e0b\uff0c\u83b7\u53d6\u552f\u4e00id\u65f6\u8c03\u7528\u7684\u65b9\u6cd5get(String)<\/code>\u7684\u6838\u5fc3\u6e90\u7801\uff08\u90e8\u5206\u7701\u7565\uff09\uff1a<\/p>\n
        \/\/ synchronized\u4fdd\u8bc1\u7ebf\u7a0b\u5b89\u5168\u95ee\u9898\npublic synchronized Result get(String key) {\n    long timestamp = System.currentTimeMillis();\n    \/\/ \u5982\u679c\u65f6\u949f\u53d1\u751f\u4e86\u56de\u62e8\n    if (timestamp < lastTimestamp) {\n        long offset = lastTimestamp - timestamp;\n        if (offset <= 5) {\n            \/\/ \u5982\u679c\u56de\u62e8\u7684\u65f6\u95f4\u57285ms\u4ee5\u5185\uff0c\u90a3\u4e48\u76f4\u63a5\u7b49\u5f85\n            wait(offset << 1);\n            timestamp = System.currentTimeMillis();\n        } else {\n            \/\/ \u5982\u679c\u8d85\u8fc75ms\uff0c\u90a3\u4e48\u76f4\u63a5\u629b\u51fa\u5f02\u5e38\n            return new Result(-3, Status.EXCEPTION);\n        }\n    }\n    \/\/ \u5982\u679c\u548c\u4e0a\u4e00\u6b21\u8bf7\u6c42\u662f\u540c\u4e00\u6beb\u79d2\u4ee5\u5185\uff0c\u90a3\u4e48sequence+1\n    if (lastTimestamp == timestamp) {\n        sequence = (sequence + 1) & sequenceMask;\n        if (sequence == 0) {\n            \/\/sequence\u4e3a0\u7684\u65f6\u5019\u8868\u793a\u8fd9\u4e00\u6beb\u79d2\u8bf7\u6c42\u91cf\u8d85\u8fc71024\uff0c\u90a3\u4e48\u81ea\u65cb\u7b49\u5f85\u4e0b\u4e00\u6beb\u79d2\n            sequence = RANDOM.nextInt(100);\n            timestamp = tilNextMillis(lastTimestamp);\n        }\n    } else {\n        \/\/\u5982\u679c\u662f\u65b0\u7684\u4e00\u6beb\u79d2\uff0c\u90a3\u4e48\u4ece\u4e00\u4e2a[0, 100)\u7684\u968f\u673a\u6570\u5f00\u59cb\uff0c\u4e4b\u6240\u4ee5\u4e0d\u662f\u6bcf\u6b21\u90fd\u4ece0\u5f00\u59cb\uff0c\u662f\u56e0\u4e3a\u9632\u6b62\u4f4e\u5e76\u53d1\u65f6\u83b7\u53d6\u7684\u552f\u4e00ID\u90fd\u662f\u5076\u6570\uff0c\u5982\u679c\u7528\u552f\u4e00ID\u4f5c\u4e3a\u5206\u7247\u952e\uff0c\u53ef\u80fd\u5bfc\u81f4\u6570\u636e\u503e\u659c\n        sequence = RANDOM.nextInt(100);\n    }\n    lastTimestamp = timestamp;\n    \/\/ \u901a\u8fc7\u4f4d\u8fd0\u7b97\u8ba1\u7b97\u6b64\u6b21\u751f\u6210\u7684\u552f\u4e00ID\n    long id = ((timestamp - twepoch) << timestampLeftShift) | (workerId << workerIdShift) | sequence;\n    return new Result(id, Status.SUCCESS);\n\n}<\/code><\/pre>\n
        \u7531\u8fd9\u6bb5\u6e90\u7801\u6211\u4eec\u53ef\u77e5\uff0cLeaf\u7684Snowflake\u6a21\u5f0f\u5e76\u6ca1\u6709\u5f7b\u5e95\u89e3\u51b3\u65f6\u949f\u56de\u62e8\u7684\u95ee\u9898<\/strong>\u3002\u5f53\u8fd0\u884c\u8fc7\u7a0b\u4e2d\uff0c\u5982\u679c\u65f6\u949f\u56de\u62e8\u8d85\u8fc75ms\uff0c\u4f9d\u7136\u4f1a\u629b\u51fa\u5f02\u5e38\u3002<\/p>\n
        \u90a3\u4e48\uff0cSnowflake<\/code>\u6a21\u5f0f\u4e3b\u8981\u89e3\u51b3\u4ec0\u4e48\u95ee\u9898\uff1f\u5f88\u660e\u663e\uff0c\u662fSnowflake<\/code>\u4e2d\u7684workerId<\/code>\u90e8\u5206<\/strong>\u3002\u5f53\u9700\u8981\u542f\u52a8\u7684Leaf\u670d\u52a1\u8d8a\u6765\u8d8a\u591a\u65f6\uff0c\u5bf9\u5176\u5206\u914dworkerId<\/code>\u662f\u4e00\u4ef6\u975e\u5e38\u4ee4\u4eba\u5934\u75bc\u7684\u4e8b\u60c5\u3002\u6211\u4eec\u8981\u505a\u7684\u662f\uff0c\u5c3d\u91cf\u8ba9\u4e00\u4ef6\u4e8b\u60c5\u7b80\u5355\u5316\uff0c\u8ba9\u7528\u6237\u65e0\u611f\u77e5\u3002\u767e\u5ea6\u7684UID\u505a\u5230\u4e86\uff08\u6587\u672b\u6709\u76f8\u5173\u9605\u8bfb\u94fe\u63a5\uff09\uff0cLeaf\u4e5f\u505a\u5230\u4e86\uff01<\/p>\n
        Leaf\u7684Snowflake<\/code>\u6a21\u5f0f\u662f\u600e\u4e48\u505a\u5230\u7684\u5462\uff1f\u5f88\u7b80\u5355\uff0c\u901a\u8fc7ZooKeeper<\/code>\u7684PERSISTENT_SEQUENTIAL<\/code>\u7c7b\u578b\u8282\u70b9\u4e3a\u6bcf\u4e00\u4e2aLeaf\u5b9e\u4f8b\u751f\u6210\u4e00\u4e2a\u9012\u589e\u7684workerId<\/code>\u3002\u4ee5\u603b\u8ba1\u90e8\u7f724\u4e2aLeaf\u5b9e\u4f8b\u4e3a\u4f8b\uff1a\u7b2c1\u4e2aLeaf\u5b9e\u4f8b\u7684workerId<\/code>\u4e3a0\uff0c\u4e14\u6839\u636e\u8be5\u5b9e\u4f8b\u7684IP\u5730\u5740\u548c\u914d\u7f6e\u7684Port\u503c\uff0c\u5373\u4f7f\u63a5\u4e0b\u6765\u91cd\u542f\uff0cworkerId<\/code>\u4ecd\u7136\u4e3a0\uff1b\u7b2c2\u4e2aLeaf\u5b9e\u4f8b\u7684workerId<\/code>\u4e3a1\uff1b\u7b2c3\u4e2aLeaf\u5b9e\u4f8b\u7684workerId<\/code>\u4e3a2\uff1b\u7b2c4\u4e2aleaf\u5b9e\u4f8b\u7684workerId<\/code>\u4e3a3\uff0c\u4ee5\u6b64\u7c7b\u63a8\u3002Leaf\u6301\u4e45\u5316\u5728ZooKeeper<\/code>\u4e2d\u7684\u6570\u636e\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n
        \/snowflake\/leaf\/forever\/\n    |--192.168.0.1\n        |--0     \n    |--192.168.0.2\n        |--1 \n    |--192.168.0.3\n        |--2 <\/code><\/pre>\n
        \u6211\u4eec\u53ef\u4ee5\u770b\u5230\u8fd9\u4e9b\u6570\u636e\u7684\u8def\u5f84\u662f\uff1a\/snowflake\/${leaf.name}\/forever\/${ip}:${port}<\/code>\u3002\u5982\u6b64\u4e00\u6765\uff0c\u5bf9\u4e8e\u6240\u6709\u90e8\u7f72\u7684Leaf\u5b9e\u4f8b\uff0c\u5176\u83b7\u53d6\u5230\u7684workerId<\/code>\u53ea\u8ddf\u5b83\u7684ip\u548cport\u6709\u5173\u3002\u5f53\u7136\uff0c\u7531\u4e8e\u5176workerId<\/code>\u536010\u4f4d\uff0c\u6240\u4ee5\uff0c\u7406\u8bba\u4e0aLeaf\u670d\u52a1\u5b9e\u4f8b\u6570\u53ef\u4ee5\u8fbe\u52301024\u4e2a\uff08\u5f88\u660e\u663e\uff0c\u8fd9\u4e2a\u5b9e\u4f8b\u6570\u4e0a\u9650\u51e0\u4e4e\u80fd\u591f\u6ee1\u8db3\u4efb\u4f55\u4e1a\u52a1\u573a\u666f\uff09\u3002<\/p>\n
        \u6700\u540e\uff0cLeaf\u4f1a\u5b9a\u671f\uff08\u95f4\u9694\u5468\u671f\u662f3\u79d2\uff09\u4e0a\u62a5\u66f4\u65b0timestamp\u3002\u5e76\u4e14\u4e0a\u62a5\u65f6\uff0c\u5982\u679c\u53d1\u73b0\u5f53\u524d\u65f6\u95f4\u6233\u5c11\u4e8e\u6700\u540e\u4e00\u6b21\u4e0a\u62a5\u7684\u65f6\u95f4\u6233\uff0c\u90a3\u4e48\u4f1a\u653e\u5f03\u4e0a\u62a5\u3002\u4e4b\u6240\u4ee5\u8fd9\u4e48\u505a\u7684\u539f\u56e0\u662f\uff0c\u9632\u6b62\u5728Leaf\u5b9e\u4f8b\u91cd\u542f\u8fc7\u7a0b\u4e2d\uff0c\u7531\u4e8e\u65f6\u949f\u56de\u62e8\u5bfc\u81f4\u53ef\u80fd\u4ea7\u751f\u91cd\u590dID\u7684\u95ee\u9898<\/strong>\uff1a<\/p>\n
        private void ScheduledUploadData(final CuratorFramework curator, final String zk_AddressNode) {\n    Executors.newSingleThreadScheduledExecutor(new ThreadFactory() {\n        @Override\n        public Thread newThread(Runnable r) {\n            Thread thread = new Thread(r, "schedule-upload-time");\n            thread.setDaemon(true);\n            return thread;\n        }\n    }).scheduleWithFixedDelay(new Runnable() {\n        @Override\n        public void run() {\n            updateNewData(curator, zk_AddressNode);\n        }\n    }, 1L, 3L, TimeUnit.SECONDS); \/\/\u6bcf3s\u4e0a\u62a5\u6570\u636e\n\n}<\/code><\/pre>\n
        \u4ea7\u751f\u91cd\u590dID\u7684\u573a\u666f\uff1a\u5047\u8bbeLeaf\u4e0d\u5b9a\u671f\u4e0a\u62a5\u5f53\u524d\u65f6\u95f4\u6233\uff0c\u90a3\u4e48\u53ef\u80fd\u4f1a\u53d1\u751f\u8fd9\u79cd\u60c5\u51b5\u5bfc\u81f4\u4ea7\u751f\u91cd\u590d\u7684ID\u3002\u5047\u8bbeLeaf\u91cd\u542f\u524d\u6700\u540e\u4e00\u6b21\u751f\u6210\u7684\u552f\u4e00ID\u662f\uff082019-05-31 08:15:00 + 12 + 168\uff09\uff0c\u5982\u679c\u8fd9\u65f6\u5019Leaf\u91cd\u542f\uff0c\u5e76\u4e14\u5728\u542f\u52a8\u4e4b\u524d\uff0c\u53d1\u751f\u4e86\u65f6\u949f\u56de\u62e8\uff08\u5047\u8bbe\u56de\u62e8\u4e8620s\uff0c\u5e76\u4e14Leaf\u5b9e\u4f8b\u542f\u52a8\u82b1\u4e8610s\uff09\uff0c\u90a3\u4e48\u5728\u8be5Leaf\u5b9e\u4f8b\u91cd\u542f\u540e\uff0c\u751f\u6210\u7684ID\u662f\uff082019-05-31 08:14:50 + 12 + 168\uff09\u3002\u5f88\u660e\u663e\u7684\u662f\uff0c\u8fd9\u4e2aID\u4ee5\u53ca\u63a5\u4e0b\u676510\u79d2\u5185\u751f\u6210\u7684ID\uff0c\u90fd\u5f88\u53ef\u80fd\u662f\u4e4b\u524d\u5df2\u7ecf\u751f\u6210\u8fc7\u7684ID\u3002<\/p>\n
        \u6211\u4eec\u518d\u770b\u4e00\u4e0b\u8c22\u7167\u4e1c\u5728\u6587\u7ae0\u300aLeaf\uff1a\u7f8e\u56e2\u70b9\u8bc4\u5206\u5e03\u5f0fID\u751f\u6210\u7cfb\u7edf\u300b\u4e2d\uff0cLeaf\u5728snowflake\u6a21\u5f0f\u4e0b\u7684\u6d41\u7a0b\u56fe\uff1a<\/p>\n
        \"leaf<\/p>\n
        \u524d\u9762\u4e00\u90e8\u5206\u903b\u8f91\uff08\u5373Leaf\u542f\u52a8\u65f6\uff0c\u6839\u636e\u81ea\u5df1\u7684ip\u548cport\u4ecezk\u4e0a\u83b7\u53d6workerId<\/code>\uff09\u662f\u548cGitHub\u4e0a\u5f00\u6e90\u4ee3\u7801\u4e00\u81f4\u7684\uff0c\u4f46\u662f\u7b14\u8005\u5728\u56fe\u4e2d\u7528\u7ea2\u8272\u6846\u4f4f\u7684\u5c31\u7565\u6709\u4e0d\u540c\u7684\uff1a<\/p>\n
        \uff081\uff09\u6821\u9a8c\u6bcf\u6b21\u5468\u671f\u6027\u4e0a\u4f20\u7684\u672c\u673a\u65f6\u95f4\u5fc5\u987b\u5927\u4e8e\u4ee5\u524d\u4e0a\u4f20\u7684\u65f6\u95f4\uff0c\u5982\u679c\u5931\u8d25\uff0c\u5e76\u6ca1\u6709\u4efb\u4f55\u52a8\u4f5c\uff08\u53ea\u662f\u7b80\u5355\u7684return\uff09\u3002
        \n\uff082\uff09\u6821\u9a8c\u6bcf\u6b21\u5468\u671f\u6027\u4e0a\u4f20\u7684\u672c\u673a\u65f6\u95f4\u5fc5\u987b\u5927\u4e8e\u4ee5\u524d\u4e0a\u4f20\u7684\u65f6\u95f4\uff0c\u5982\u679c\u6210\u529f\uff0c\u76f4\u63a5\u4e0a\u62a5\u3002\u5e76\u4e0d\u4f1a\u5f97\u5230leaf_temporary<\/code>\u4e0b\u6240\u6709\u8282\u70b9\uff0c\u7136\u540e\u5f97\u5230\u5404\u4e2a\u6b63\u5728\u670d\u52a1\u7684\u673a\u5668\u65f6\u95f4\u5e76\u505a\u5e73\u5747\u503c\u6821\u9a8c\u3002<\/p>\n
        \u8fd9\u5757\u903b\u8f91\u5bf9\u5e94\u7684\u6e90\u7801\u5c31\u662fScheduledUploadData()<\/code>\u4e2d\u8c03\u7528\u7684\u65b9\u6cd5updateNewData(curator, zk_AddressNode)<\/code>\uff0c\u5176\u6e90\u7801\u5982\u4e0b\uff1a<\/p>\n
        private void updateNewData(CuratorFramework curator, String path) {\n    try {\n        if (System.currentTimeMillis() < lastUpdateTime) {\n            return;\n        }\n        curator.setData().forPath(path, buildData().getBytes());\n        lastUpdateTime = System.currentTimeMillis();\n    } catch (Exception e) {\n        LOGGER.info("update init data error path is {} error is {}", path, e);\n    }\n}<\/code><\/pre>\n
        \u731c\u6d4b\u53ef\u80fd\u662f\u5f00\u6e90\u7248\u672c\u548c\u7f8e\u56e2\u5185\u90e8\u7248\u672c\u53ef\u80fd\u5b58\u5728\u51fa\u5165\u3002<\/p>\n
        \u5256\u6790leaf\uff0c\u5c31\u4e0d\u5f97\u4e0d\u63d0\u767e\u5ea6\u7684uid\uff0cuid\u662f\u5f00\u6e90\u5206\u5e03\u5f0fID\u65b9\u6848\u4e2d\uff0c\u6700\u5f7b\u5e95\u89e3\u51b3\u65f6\u949f\u56de\u62e8\u7684\u65b9\u6848\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
        \u7f8e\u56e2\u70b9\u8bc4\u5f00\u6e90\u5206\u5e03\u5f0fID\u751f\u6210\u7cfb\u7edfLeaf\uff1ahttps:\/\/github.com\/Meituan-Dianping […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[438],"class_list":["post-1737","post","type-post","status-publish","format-standard","hentry","category-distributed","tag-leaf"],"_links":{"self":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts\/1737","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/comments?post=1737"}],"version-history":[{"count":0,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts\/1737\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1737"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1737"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1737"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}