{"id":1680,"date":"2022-11-23T23:07:22","date_gmt":"2022-11-23T15:07:22","guid":{"rendered":"https:\/\/qaqaq.top\/?p=1680"},"modified":"2022-11-27T12:40:57","modified_gmt":"2022-11-27T04:40:57","slug":"redo%e6%97%a5%e5%bf%97%e5%92%8cundo%e6%97%a5%e5%bf%97%e7%9a%84%e7%90%86%e8%a7%a3%e3%80%81%e4%b8%ba%e4%bb%80%e4%b9%88%e9%9c%80%e8%a6%81redo%e6%97%a5%e5%bf%97%e3%80%81redo%e6%97%a5%e5%bf%97%e7%9a%84","status":"publish","type":"post","link":"https:\/\/qaqaq.top\/?p=1680","title":{"rendered":"Redo\u65e5\u5fd7\u548cUndo\u65e5\u5fd7\u7684\u7406\u89e3\u3001\u4e3a\u4ec0\u4e48\u9700\u8981Redo\u65e5\u5fd7\u3001Redo\u65e5\u5fd7\u7684\u5237\u76d8\u7b56\u7565\u4e0e\u8fc7\u7a0b\u5256\u6790\u3001\u5199\u5165Redo Log Buffer\u548cRedo Log File\u7684\u5199\u5165\u7b56\u7565\u3001Undo\u65e5\u5fd7\u7684\u6982\u8ff0\u4e0e\u5199\u5165\u8fc7\u7a0b"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code># \u7b2c14\u7ae0_MySQL\u4e8b\u52a1\u65e5\u5fd7\r\n\r\n#10-\u4e8b\u52a1\u65e5\u5fd7\r\n\r\n# \u4e8b\u52a1\u67094\u79cd\u7279\u6027\uff1a\u539f\u5b50\u6027\u3001\u4e00\u81f4\u6027\u3001\u9694\u79bb\u6027\u548c\u6301\u4e45\u6027\u3002\u90a3\u4e48\u4e8b\u52a1\u7684\u56db\u79cd\u7279\u6027\u5230\u5e95\u662f\u57fa\u4e8e\u4ec0\u4e48\u673a\u5236\u5b9e\u73b0\u5462\uff1f\r\n#     \u4e8b\u52a1\u7684\u9694\u79bb\u6027\u7531 \u9501\u673a\u5236 \u5b9e\u73b0\u3002\r\n#     \u800c\u4e8b\u52a1\u7684\u539f\u5b50\u6027\u3001\u4e00\u81f4\u6027\u548c\u6301\u4e45\u6027\u7531\u4e8b\u52a1\u7684 redo \u65e5\u5fd7\u548cundo \u65e5\u5fd7\u6765\u4fdd\u8bc1\u3002\r\n#         REDO LOG \u79f0\u4e3a \u91cd\u505a\u65e5\u5fd7 \uff0c\u63d0\u4f9b\u518d\u5199\u5165\u64cd\u4f5c\uff0c\u6062\u590d\u63d0\u4ea4\u4e8b\u52a1\u4fee\u6539\u7684\u9875\u64cd\u4f5c\uff0c\u7528\u6765\u4fdd\u8bc1\u4e8b\u52a1\u7684\u6301\u4e45\u6027\u3002\r\n#         UNDO LOG \u79f0\u4e3a \u56de\u6eda\u65e5\u5fd7 \uff0c\u56de\u6eda\u884c\u8bb0\u5f55\u5230\u67d0\u4e2a\u7279\u5b9a\u7248\u672c\uff0c\u7528\u6765\u4fdd\u8bc1\u4e8b\u52a1\u7684\u539f\u5b50\u6027\u3001\u4e00\u81f4\u6027\u3002\r\n# \u6709\u7684DBA\u6216\u8bb8\u4f1a\u8ba4\u4e3a UNDO \u662f REDO \u7684\u9006\u8fc7\u7a0b\uff0c\u5176\u5b9e\u4e0d\u7136\u3002\r\n\r\n# 1. redo\u65e5\u5fd7\r\n\r\n# 1.1 \u4e3a\u4ec0\u4e48\u9700\u8981REDO\u65e5\u5fd7\r\n# \u4e00\u65b9\u9762\uff0c\u7f13\u51b2\u6c60\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u6d88\u9664CPU\u548c\u78c1\u76d8\u4e4b\u95f4\u7684\u9e3f\u6c9f\uff0ccheckpoint\u673a\u5236\u53ef\u4ee5\u4fdd\u8bc1\u6570\u636e\u7684\u6700\u7ec8\u843d\u76d8\uff0c\r\n# \u7136\u800c\u7531\u4e8echeckpoint \u5e76\u4e0d\u662f\u6bcf\u6b21\u53d8\u66f4\u7684\u65f6\u5019\u5c31\u89e6\u53d1 \u7684\uff0c\u800c\u662fmaster\u7ebf\u7a0b\u9694\u4e00\u6bb5\u65f6\u95f4\u53bb\u5904\u7406\u7684\u3002\r\n# \u6240\u4ee5\u6700\u574f\u7684\u60c5\u51b5\u5c31\u662f\u4e8b\u52a1\u63d0\u4ea4\u540e\uff0c\u521a\u5199\u5b8c\u7f13\u51b2\u6c60\uff0c\u6570\u636e\u5e93\u5b95\u673a\u4e86\uff0c\u90a3\u4e48\u8fd9\u6bb5\u6570\u636e\u5c31\u662f\u4e22\u5931\u7684\uff0c\u65e0\u6cd5\u6062\u590d\u3002\r\n\r\n# \u53e6\u4e00\u65b9\u9762\uff0c\u4e8b\u52a1\u5305\u542b \u6301\u4e45\u6027 \u7684\u7279\u6027\uff0c\u5c31\u662f\u8bf4\u5bf9\u4e8e\u4e00\u4e2a\u5df2\u7ecf\u63d0\u4ea4\u7684\u4e8b\u52a1\uff0c\u5728\u4e8b\u52a1\u63d0\u4ea4\u540e\u5373\u4f7f\u7cfb\u7edf\u53d1\u751f\u4e86\u5d29\u6e83\uff0c\r\n# \u8fd9\u4e2a\u4e8b\u52a1\u5bf9\u6570\u636e\u5e93\u4e2d\u6240\u505a\u7684\u66f4\u6539\u4e5f\u4e0d\u80fd\u4e22\u5931\u3002\r\n\r\n# \u90a3\u4e48\u5982\u4f55\u4fdd\u8bc1\u8fd9\u4e2a\u6301\u4e45\u6027\u5462\uff1f \u4e00\u4e2a\u7b80\u5355\u7684\u505a\u6cd5 \uff1a\u5728\u4e8b\u52a1\u63d0\u4ea4\u5b8c\u6210\u4e4b\u524d\u628a\u8be5\u4e8b\u52a1\u6240\u4fee\u6539\u7684\u6240\u6709\u9875\u9762\u90fd\u5237\u65b0\u5230\u78c1\u76d8\uff0c\r\n# \u4f46\u662f\u8fd9\u4e2a\u7b80\u5355\u7c97\u66b4\u7684\u505a\u6cd5\u6709\u4e9b\u95ee\u9898\r\n\r\n# \u53e6\u4e00\u4e2a\u89e3\u51b3\u7684\u601d\u8def \uff1a\u6211\u4eec\u53ea\u662f\u60f3\u8ba9\u5df2\u7ecf\u63d0\u4ea4\u4e86\u7684\u4e8b\u52a1\u5bf9\u6570\u636e\u5e93\u4e2d\u6570\u636e\u6240\u505a\u7684\u4fee\u6539\u6c38\u4e45\u751f\u6548\uff0c\u5373\u4f7f\u540e\u6765\u7cfb\u7edf\u5d29\u6e83\uff0c\r\n# \u5728\u91cd\u542f\u540e\u4e5f\u80fd\u628a\u8fd9\u79cd\u4fee\u6539\u6062\u590d\u51fa\u6765\u3002\r\n# \u6240\u4ee5\u6211\u4eec\u5176\u5b9e\u6ca1\u6709\u5fc5\u8981\u5728\u6bcf\u6b21\u4e8b\u52a1\u63d0\u4ea4\u65f6\u5c31\u628a\u8be5\u4e8b\u52a1\u5728\u5185\u5b58\u4e2d\u4fee\u6539\u8fc7\u7684\u5168\u90e8\u9875\u9762\u5237\u65b0\u5230\u78c1\u76d8\uff0c\r\n# \u53ea\u9700\u8981\u628a \u4fee\u6539 \u4e86\u54ea\u4e9b\u4e1c\u897f \u8bb0\u5f55\u4e00\u4e0b \u5c31\u597d\u3002\u6bd4\u5982\uff0c\r\n# \u67d0\u4e2a\u4e8b\u52a1\u5c06\u7cfb\u7edf\u8868\u7a7a\u95f4\u4e2d \u7b2c10\u53f7 \u9875\u9762\u4e2d\u504f\u79fb\u91cf\u4e3a 100 \u5904\u7684\u90a3\u4e2a\u5b57\u8282\u7684\u503c 1 \u6539\u6210 2 \u3002\u6211\u4eec\u53ea\u9700\u8981\u8bb0\u5f55\u4e00\u4e0b\uff1a\r\n# \u5c06\u7b2c0\u53f7\u8868\u7a7a\u95f4\u768410\u53f7\u9875\u9762\u7684\u504f\u79fb\u91cf\u4e3a100\u5904\u7684\u503c\u66f4\u65b0\u4e3a 2 \u3002\r\n\r\n# 1.2 REDO\u65e5\u5fd7\u7684\u597d\u5904\u3001\u7279\u70b9\r\n# 1. \u597d\u5904\r\n#     redo\u65e5\u5fd7\u964d\u4f4e\u4e86\u5237\u76d8\u9891\u7387\r\n#     redo\u65e5\u5fd7\u5360\u7528\u7684\u7a7a\u95f4\u975e\u5e38\u5c0f\r\n# 2. \u7279\u70b9\r\n#     redo\u65e5\u5fd7\u662f\u987a\u5e8f\u5199\u5165\u78c1\u76d8\u7684\r\n#     \u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\uff0credo log\u4e0d\u65ad\u8bb0\u5f55\r\n\r\n# 1.3 redo\u7684\u7ec4\u6210\r\n# Redo log\u53ef\u4ee5\u7b80\u5355\u5206\u4e3a\u4ee5\u4e0b\u4e24\u4e2a\u90e8\u5206\uff1a\r\n\r\n# \u91cd\u505a\u65e5\u5fd7\u7684\u7f13\u51b2 (redo log buffer) \uff0c\u4fdd\u5b58\u5728\u5185\u5b58\u4e2d\uff0c\u662f\u6613\u5931\u7684\u3002\r\n# \u53c2\u6570\u8bbe\u7f6e\uff1ainnodb_log_buffer_size\uff1a\r\n# redo log buffer \u5927\u5c0f\uff0c\u9ed8\u8ba4 16M \uff0c\u6700\u5927\u503c\u662f4096M\uff0c\u6700\u5c0f\u503c\u4e3a1M\u3002\r\nSHOW VARIABLES LIKE '%innodb_log_buffer_size%';\r\n\r\n# \u91cd\u505a\u65e5\u5fd7\u6587\u4ef6 (redo log file) \uff0c\u4fdd\u5b58\u5728\u786c\u76d8\u4e2d\uff0c\u662f\u6301\u4e45\u7684\u3002\r\n\r\n# 1.4 redo\u7684\u6574\u4f53\u6d41\u7a0b\r\n# \u4ee5\u4e00\u4e2a\u66f4\u65b0\u4e8b\u52a1\u4e3a\u4f8b\uff0credo log \u6d41\u8f6c\u8fc7\u7a0b\uff0c\r\n\r\n# \u7b2c1\u6b65\uff1a\u5148\u5c06\u539f\u59cb\u6570\u636e\u4ece\u78c1\u76d8\u4e2d\u8bfb\u5165\u5185\u5b58\u4e2d\u6765\uff0c\u4fee\u6539\u6570\u636e\u7684\u5185\u5b58\u62f7\u8d1d\r\n# \u7b2c2\u6b65\uff1a\u751f\u6210\u4e00\u6761\u91cd\u505a\u65e5\u5fd7\u5e76\u5199\u5165redo log buffer\uff0c\u8bb0\u5f55\u7684\u662f\u6570\u636e\u88ab\u4fee\u6539\u540e\u7684\u503c\r\n# \u7b2c3\u6b65\uff1a\u5f53\u4e8b\u52a1commit\u65f6\uff0c\u5c06redo log buffer\u4e2d\u7684\u5185\u5bb9\u5237\u65b0\u5230 redo log file\uff0c\u5bf9 redo log file\u91c7\u7528\u8ffd\u52a0\u5199\u7684\u65b9\u5f0f\r\n# \u7b2c4\u6b65\uff1a\u5b9a\u671f\u5c06\u5185\u5b58\u4e2d\u4fee\u6539\u7684\u6570\u636e\u5237\u65b0\u5230\u78c1\u76d8\u4e2d\r\n\r\n# \u4f53\u4f1a\uff1a\r\n# Write-Ahead Log(\u9884\u5148\u65e5\u5fd7\u6301\u4e45\u5316)\uff1a\u5728\u6301\u4e45\u5316\u4e00\u4e2a\u6570\u636e\u9875\u4e4b\u524d\uff0c\u5148\u5c06\u5185\u5b58\u4e2d\u76f8\u5e94\u7684\u65e5\u5fd7\u9875\u6301\u4e45\u5316\u3002\r\n\r\n# 1.5 redo log\u7684\u5237\u76d8\u7b56\u7565\r\n# redo log\u7684\u5199\u5165\u5e76\u4e0d\u662f\u76f4\u63a5\u5199\u5165\u78c1\u76d8\u7684\uff0cInnoDB\u5f15\u64ce\u4f1a\u5728\u5199redo log\u7684\u65f6\u5019\u5148\u5199redo log buffer\uff0c\r\n# \u4e4b\u540e\u4ee5 \u4e00\u5b9a\u7684\u9891\u7387 \u5237\u5165\u5230\u771f\u6b63\u7684redo log file \u4e2d\u3002\u8fd9\u91cc\u7684\u4e00\u5b9a\u9891\u7387\u600e\u4e48\u770b\u5f85\u5462\uff1f\u8fd9\u5c31\u662f\u6211\u4eec\u8981\u8bf4\u7684\u5237\u76d8\u7b56\u7565\u3002\r\n\r\n# \u6ce8\u610f\uff0credo log buffer\u5237\u76d8\u5230redo log file\u7684\u8fc7\u7a0b\u5e76\u4e0d\u662f\u771f\u6b63\u7684\u5237\u5230\u78c1\u76d8\u4e2d\u53bb\uff0c\r\n# \u53ea\u662f\u5237\u5165\u5230 \u6587\u4ef6\u7cfb\u7edf\u7f13\u5b58\uff08page cache\uff09\u4e2d\u53bb\uff08\u8fd9\u662f\u73b0\u4ee3\u64cd\u4f5c\u7cfb\u7edf\u4e3a\u4e86\u63d0\u9ad8\u6587\u4ef6\u5199\u5165\u6548\u7387\u505a\u7684\u4e00\u4e2a\u4f18\u5316\uff09\uff0c\r\n# \u771f\u6b63\u7684\u5199\u5165\u4f1a\u4ea4\u7ed9\u7cfb\u7edf\u81ea\u5df1\u6765\u51b3\u5b9a\uff08\u6bd4\u5982page cache\u8db3\u591f\u5927\u4e86\uff09\u3002\u90a3\u4e48\u5bf9\u4e8eInnoDB\u6765\u8bf4\u5c31\u5b58\u5728\u4e00\u4e2a\u95ee\u9898\uff0c\r\n# \u5982\u679c\u4ea4\u7ed9\u7cfb\u7edf\u6765\u540c\u6b65\uff0c\u540c\u6837\u5982\u679c\u7cfb\u7edf\u5b95\u673a\uff0c\u90a3\u4e48\u6570\u636e\u4e5f\u4e22\u5931\u4e86\uff08\u867d\u7136\u6574\u4e2a\u7cfb\u7edf\u5b95\u673a\u7684\u6982\u7387\u8fd8\u662f\u6bd4\u8f83\u5c0f\u7684\uff09\u3002\r\n\r\n# \u9488\u5bf9\u8fd9\u79cd\u60c5\u51b5\uff0cInnoDB\u7ed9\u51fa innodb_flush_log_at_trx_commit \u53c2\u6570\uff0c\u8be5\u53c2\u6570\u63a7\u5236 commit\u63d0\u4ea4\u4e8b\u52a1\u65f6\uff0c\r\n# \u5982\u4f55\u5c06 redo log buffer \u4e2d\u7684\u65e5\u5fd7\u5237\u65b0\u5230 redo log file \u4e2d\u3002\u5b83\u652f\u6301\u4e09\u79cd\u7b56\u7565\uff1a\r\n#     \u8bbe\u7f6e\u4e3a0 \uff1a\u8868\u793a\u6bcf\u6b21\u4e8b\u52a1\u63d0\u4ea4\u65f6\u4e0d\u8fdb\u884c\u5237\u76d8\u64cd\u4f5c\u3002\uff08\u7cfb\u7edf\u9ed8\u8ba4master thread\u6bcf\u96941s\u8fdb\u884c\u4e00\u6b21\u91cd\u505a\u65e5\u5fd7\u7684\u540c\u6b65\uff09\r\n#     \u8bbe\u7f6e\u4e3a1 \uff1a\u8868\u793a\u6bcf\u6b21\u4e8b\u52a1\u63d0\u4ea4\u65f6\u90fd\u5c06\u8fdb\u884c\u540c\u6b65\uff0c\u5237\u76d8\u64cd\u4f5c\uff08 \u9ed8\u8ba4\u503c \uff09\r\n#     \u8bbe\u7f6e\u4e3a2 \uff1a\u8868\u793a\u6bcf\u6b21\u4e8b\u52a1\u63d0\u4ea4\u65f6\u90fd\u53ea\u628a redo log buffer \u5185\u5bb9\u5199\u5165 page cache\uff0c\u4e0d\u8fdb\u884c\u540c\u6b65\u3002\r\n# \u7531os\u81ea\u5df1\u51b3\u5b9a\u4ec0\u4e48\u65f6\u5019\u540c\u6b65\u5230\u78c1\u76d8\u6587\u4ef6\u3002\r\n\r\nSHOW VARIABLES LIKE 'innodb_flush_log_at_trx_commit';\r\n\r\n# 1.6 \u4e0d\u540c\u5237\u76d8\u7b56\u7565\u6f14\u793a\r\n\r\n# \u2461. \u4e3e\u4f8b\r\n\r\nUSE atguigudb3;\r\n\r\nCREATE TABLE test_load(\r\n    a INT,\r\n    b CHAR(80)\r\n)ENGINE=INNODB;\r\n\r\n#\u521b\u5efa\u5b58\u50a8\u8fc7\u7a0b\uff0c\u7528\u4e8e\u5411test_load\u4e2d\u6dfb\u52a0\u6570\u636e\r\nDELIMITER \/\/\r\nCREATE PROCEDURE p_load(COUNT INT UNSIGNED)\r\nBEGIN\r\n    DECLARE s INT UNSIGNED DEFAULT 1;\r\n    DECLARE c CHAR(80)DEFAULT REPEAT('a',80);\r\n    WHILE s&lt;=COUNT DO\r\n        INSERT INTO test_load SELECT NULL,c;\r\n        COMMIT;\r\n        SET s=s+1;\r\n    END WHILE;\r\nEND \/\/\r\nDELIMITER ;\r\n\r\n#\u6d4b\u8bd51\uff1a\r\n#\u8bbe\u7f6e\u5e76\u67e5\u770b\uff1ainnodb_flush_log_at_trx_commit\r\n\r\nSHOW VARIABLES LIKE 'innodb_flush_log_at_trx_commit';\r\n\r\n# SET GLOBAL innodb_flush_log_at_trx_commit = 1;\r\n\r\n#\u8c03\u7528\u5b58\u50a8\u8fc7\u7a0b\r\nCALL p_load(30000); #27 s 277 ms\r\n\r\n#\u6d4b\u8bd52\uff1a\r\nTRUNCATE TABLE test_load;\r\n\r\nSELECT COUNT(*) FROM test_load;\r\n\r\nSET GLOBAL innodb_flush_log_at_trx_commit = 0;\r\n\r\nSHOW VARIABLES LIKE 'innodb_flush_log_at_trx_commit';\r\n\r\n#\u8c03\u7528\u5b58\u50a8\u8fc7\u7a0b\r\nCALL p_load(30000); #16 s 551 ms\r\n\r\n#\u6d4b\u8bd53\uff1a\r\nTRUNCATE TABLE test_load;\r\n\r\nSELECT COUNT(*) FROM test_load;\r\n\r\nSET GLOBAL innodb_flush_log_at_trx_commit = 2;\r\n\r\nSHOW VARIABLES LIKE 'innodb_flush_log_at_trx_commit';\r\n\r\n#\u8c03\u7528\u5b58\u50a8\u8fc7\u7a0b\r\nCALL p_load(30000); #18 s 840 ms\r\n\r\n# 1.7 \u5199\u5165redo log buffer \u8fc7\u7a0b \u89c1\u8bfe\u4ef6\r\n\r\n# 1.8 redo log file\r\n\r\n# 1. \u76f8\u5173\u53c2\u6570\u8bbe\u7f6e\r\n\r\n# innodb_log_group_home_dir \uff1a\u6307\u5b9a redo log \u6587\u4ef6\u7ec4\u6240\u5728\u7684\u8def\u5f84\uff0c\u9ed8\u8ba4\u503c\u4e3a .\/ \uff0c\u8868\u793a\u5728\u6570\u636e\u5e93\u7684\u6570\u636e\u76ee\u5f55\u4e0b\u3002\r\n# MySQL\u7684\u9ed8\u8ba4\u6570\u636e\u76ee\u5f55\uff08 var\/lib\/mysql \uff09\u4e0b\u9ed8\u8ba4\u6709\u4e24\u4e2a\u540d\u4e3a ib_logfile0 \u548cib_logfile1 \u7684\u6587\u4ef6\uff0c\r\n# log buffer\u4e2d\u7684\u65e5\u5fd7\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u5c31\u662f\u5237\u65b0\u5230\u8fd9\u4e24\u4e2a\u78c1\u76d8\u6587\u4ef6\u4e2d\u3002\u6b64redo\u65e5\u5fd7\u6587\u4ef6\u4f4d\u7f6e\u8fd8\u53ef\u4ee5\u4fee\u6539\u3002\r\nSHOW VARIABLES LIKE 'innodb_log_group_home_dir';\r\n\r\n# innodb_log_files_in_group\uff1a\u6307\u660eredo log file\u7684\u4e2a\u6570\uff0c\u547d\u540d\u65b9\u5f0f\u5982\uff1aib_logfile0\uff0c\r\n# iblogfile1... iblogfilen\u3002\u9ed8\u8ba42\u4e2a\uff0c\u6700\u5927100\u4e2a\u3002\r\nSHOW VARIABLES LIKE 'innodb_log_files_in_group';\r\n\r\n# innodb_flush_log_at_trx_commit\uff1a\u63a7\u5236 redo log \u5237\u65b0\u5230\u78c1\u76d8\u7684\u7b56\u7565\uff0c\u9ed8\u8ba4\u4e3a1\u3002\r\n\r\n# innodb_log_file_size\uff1a\u5355\u4e2a redo log \u6587\u4ef6\u8bbe\u7f6e\u5927\u5c0f\uff0c\u9ed8\u8ba4\u503c\u4e3a 48M \u3002\u6700\u5927\u503c\u4e3a512G\uff0c\r\n# \u6ce8\u610f\u6700\u5927\u503c\u6307\u7684\u662f\u6574\u4e2a redo log \u7cfb\u5217\u6587\u4ef6\u4e4b\u548c\uff0c\r\n# \u5373\uff08innodb_log_files_in_group * innodb_log_file_size \uff09\u4e0d\u80fd\u5927\u4e8e\u6700\u5927\u503c512G\u3002\r\nSHOW VARIABLES LIKE 'innodb_log_file_size';\r\n\r\n# \u6839\u636e\u4e1a\u52a1\u4fee\u6539\u5176\u5927\u5c0f\uff0c\u4ee5\u4fbf\u5bb9\u7eb3\u8f83\u5927\u7684\u4e8b\u52a1\u3002\u7f16\u8f91my.cnf\u6587\u4ef6\u5e76\u91cd\u542f\u6570\u636e\u5e93\u751f\u6548\r\n# LINUX\u4e0b\u6267\u884c\r\n# vim \/etc\/my.cnf\r\n# innodb_log_file_size=200M\r\n\r\n# 2. \u65e5\u5fd7\u6587\u4ef6\u7ec4\r\n# \u603b\u5171\u7684redo\u65e5\u5fd7\u6587\u4ef6\u5927\u5c0f\u5176\u5b9e\u5c31\u662f\uff1a innodb_log_file_size \u00d7 innodb_log_files_in_group \u3002\r\n\r\n# \u91c7\u7528\u5faa\u73af\u4f7f\u7528\u7684\u65b9\u5f0f\u5411redo\u65e5\u5fd7\u6587\u4ef6\u7ec4\u91cc\u5199\u6570\u636e\u7684\u8bdd\uff0c\u4f1a\u5bfc\u81f4\u540e\u5199\u5165\u7684redo\u65e5\u5fd7\u8986\u76d6\u6389\u524d\u8fb9\u5199\u7684redo\u65e5\u5fd7\uff1f\r\n# \u5f53\u7136\uff01\u6240\u4ee5InnoDB\u7684\u8bbe\u8ba1\u8005\u63d0\u51fa\u4e86checkpoint\u7684\u6982\u5ff5\u3002\r\n\r\n# 3. checkpoint\r\n# \u5982\u679c write pos \u8ffd\u4e0a checkpoint \uff0c\u8868\u793a\u65e5\u5fd7\u6587\u4ef6\u7ec4\u6ee1\u4e86\uff0c\u8fd9\u65f6\u5019\u4e0d\u80fd\u518d\u5199\u5165\u65b0\u7684 redo log\u8bb0\u5f55\uff0c\r\n# MySQL \u5f97\u505c\u4e0b\u6765\uff0c\u6e05\u7a7a\u4e00\u4e9b\u8bb0\u5f55\uff0c\u628a checkpoint \u63a8\u8fdb\u4e00\u4e0b\u3002\r\n\r\n# 1.9 redo log \u5c0f\u7ed3\r\n# InnoDB\u7684\u66f4\u65b0\u64cd\u4f5c\u91c7\u7528\u7684\u662fWrite Ahead Log\uff08\u9884\u5148\u65e5\u5fd7\u6301\u4e45\u5316\uff09\u7b56\u7565\uff0c\u5373\u5148\u5199\u65e5\u5fd7\uff0c\u518d\u5199\u5165\u78c1\u76d8\u3002\r\n\r\n# 2. Undo\u65e5\u5fd7\r\n\r\n# redo log\u662f\u4e8b\u52a1\u6301\u4e45\u6027\u7684\u4fdd\u8bc1\uff0cundo log\u662f\u4e8b\u52a1\u539f\u5b50\u6027\u7684\u4fdd\u8bc1\u3002\r\n# \u5728\u4e8b\u52a1\u4e2d \u66f4\u65b0\u6570\u636e \u7684 \u524d\u7f6e\u64cd\u4f5c \u5176\u5b9e\u662f\u8981\u5148\u5199\u5165\u4e00\u4e2a undo log \u3002\r\n\r\n# 2.1 \u5982\u4f55\u7406\u89e3Undo\u65e5\u5fd7\r\n\r\n# \u4e8b\u52a1\u9700\u8981\u4fdd\u8bc1 \u539f\u5b50\u6027 \uff0c\u4e5f\u5c31\u662f\u4e8b\u52a1\u4e2d\u7684\u64cd\u4f5c\u8981\u4e48\u5168\u90e8\u5b8c\u6210\uff0c\u8981\u4e48\u4ec0\u4e48\u4e5f\u4e0d\u505a\u3002\r\n# \u4f46\u6709\u65f6\u5019\u4e8b\u52a1\u6267\u884c\u5230\u4e00\u534a\u4f1a\u51fa\u73b0\u4e00\u4e9b\u60c5\u51b5\uff0c\u6bd4\u5982\uff1a\r\n\r\n#     \u60c5\u51b5\u4e00\uff1a\u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\u53ef\u80fd\u9047\u5230\u5404\u79cd\u9519\u8bef\uff0c\u6bd4\u5982 \u670d\u52a1\u5668\u672c\u8eab\u7684\u9519\u8bef \uff0c \u64cd\u4f5c\u7cfb\u7edf\u9519\u8bef \uff0c\r\n# \u751a\u81f3\u662f\u7a81\u7136 \u65ad\u7535 \u5bfc\u81f4\u7684\u9519\u8bef\u3002\r\n#     \u60c5\u51b5\u4e8c\uff1a\u7a0b\u5e8f\u5458\u53ef\u4ee5\u5728\u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\u624b\u52a8\u8f93\u5165 ROLLBACK \u8bed\u53e5\u7ed3\u675f\u5f53\u524d\u4e8b\u52a1\u7684\u6267\u884c\u3002\r\n\r\n# \u4ee5\u4e0a\u60c5\u51b5\u51fa\u73b0\uff0c\u6211\u4eec\u9700\u8981\u628a\u6570\u636e\u6539\u56de\u539f\u5148\u7684\u6837\u5b50\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u79f0\u4e4b\u4e3a \u56de\u6eda \uff0c\u8fd9\u6837\u5c31\u53ef\u4ee5\u9020\u6210\u4e00\u4e2a\u5047\u8c61\uff1a\r\n# \u8fd9\u4e2a\u4e8b\u52a1\u770b\u8d77\u6765\u4ec0\u4e48\u90fd\u6ca1\u505a\uff0c\u6240\u4ee5\u7b26\u5408 \u539f\u5b50\u6027 \u8981\u6c42\u3002\r\n\r\n# 2.2 Undo\u65e5\u5fd7\u7684\u4f5c\u7528\r\n\r\n# \u4f5c\u75281\uff1a\u56de\u6eda\u6570\u636e\r\n# \u4f5c\u75282\uff1aMVCC\r\n\r\n# 2.3 undo\u7684\u5b58\u50a8\u7ed3\u6784\r\n\r\n# 1. \u56de\u6eda\u6bb5\u4e0eundo\u9875\r\n# InnoDB\u5bf9undo log\u7684\u7ba1\u7406\u91c7\u7528\u6bb5\u7684\u65b9\u5f0f\uff0c\u4e5f\u5c31\u662f \u56de\u6eda\u6bb5\uff08rollback segment\uff09 \u3002\r\n# \u6bcf\u4e2a\u56de\u6eda\u6bb5\u8bb0\u5f55\u4e861024 \u4e2a undo log segment \uff0c\u800c\u5728\u6bcf\u4e2aundo log segment\u6bb5\u4e2d\u8fdb\u884c undo\u9875 \u7684\u7533\u8bf7\u3002\r\n\r\n#     \u5728 InnoDB1.1\u7248\u672c\u4e4b\u524d \uff08\u4e0d\u5305\u62ec1.1\u7248\u672c\uff09\uff0c\u53ea\u6709\u4e00\u4e2arollback segment\uff0c\r\n# \u56e0\u6b64\u652f\u6301\u540c\u65f6\u5728\u7ebf\u7684\u4e8b\u52a1\u9650\u5236\u4e3a 1024 \u3002\u867d\u7136\u5bf9\u7edd\u5927\u591a\u6570\u7684\u5e94\u7528\u6765\u8bf4\u90fd\u5df2\u7ecf\u591f\u7528\u3002\r\n\r\n#     \u4ece1.1\u7248\u672c\u5f00\u59cbInnoDB\u652f\u6301\u6700\u5927 128\u4e2arollback segment \uff0c\u6545\u5176\u652f\u6301\u540c\u65f6\u5728\u7ebf\u7684\u4e8b\u52a1\u9650\u5236\u63d0\u9ad8\u5230\u4e86 128*1024 \u3002\r\n\r\n#\u8bbe\u7f6erollback segment\u6587\u4ef6\u6240\u5728\u7684\u8def\u5f84\u3002\r\nSHOW VARIABLES LIKE 'innodb_undo_directory';\r\n\r\n#\u8bbe\u7f6erollback segment\u7684\u4e2a\u6570\u3002\r\nSHOW VARIABLES LIKE 'innodb_undo_logs';\r\n\r\n#\u8bbe\u7f6e\u6784\u6210rollback segment\u6587\u4ef6\u7684\u6570\u91cf\u3002\r\nSHOW VARIABLES LIKE 'innodb_undo_tablespaces';\r\n\r\n# 2. \u56de\u6eda\u6bb5\u4e0e\u4e8b\u52a1\r\n# 1. \u6bcf\u4e2a\u4e8b\u52a1\u53ea\u4f1a\u4f7f\u7528\u4e00\u4e2a\u56de\u6eda\u6bb5\uff0c\u4e00\u4e2a\u56de\u6eda\u6bb5\u5728\u540c\u4e00\u65f6\u523b\u53ef\u80fd\u4f1a\u670d\u52a1\u4e8e\u591a\u4e2a\u4e8b\u52a1\u3002\r\n\r\n# 2. \u5f53\u4e00\u4e2a\u4e8b\u52a1\u5f00\u59cb\u7684\u65f6\u5019\uff0c\u4f1a\u5236\u5b9a\u4e00\u4e2a\u56de\u6eda\u6bb5\uff0c\u5728\u4e8b\u52a1\u8fdb\u884c\u7684\u8fc7\u7a0b\u4e2d\uff0c\u5f53\u6570\u636e\u88ab\u4fee\u6539\u65f6\uff0c\r\n# \u539f\u59cb\u7684\u6570\u636e\u4f1a\u88ab\u590d\u5236\u5230\u56de\u6eda\u6bb5\u3002\r\n\r\n# 3. \u5728\u56de\u6eda\u6bb5\u4e2d\uff0c\u4e8b\u52a1\u4f1a\u4e0d\u65ad\u586b\u5145\u76d8\u533a\uff0c\u76f4\u5230\u4e8b\u52a1\u7ed3\u675f\u6216\u6240\u6709\u7684\u7a7a\u95f4\u88ab\u7528\u5b8c\u3002\u5982\u679c\u5f53\u524d\u7684\u76d8\u533a\u4e0d\u591f\u7528\uff0c\r\n# \u4e8b\u52a1\u4f1a\u5728\u6bb5\u4e2d\u8bf7\u6c42\u6269\u5c55\u4e0b\u4e00\u4e2a\u76d8\u533a\uff0c\u5982\u679c\u6240\u6709\u5df2\u5206\u914d\u7684\u76d8\u533a\u90fd\u88ab\u7528\u5b8c\uff0c\r\n# \u4e8b\u52a1\u4f1a\u8986\u76d6\u6700\u521d\u7684\u76d8\u533a\u6216\u8005\u5728\u56de\u6eda\u6bb5\u5141\u8bb8\u7684\u60c5\u51b5\u4e0b\u6269\u5c55\u65b0\u7684\u76d8\u533a\u6765\u4f7f\u7528\u3002\r\n\r\n# 4. \u56de\u6eda\u6bb5\u5b58\u5728\u4e8eundo\u8868\u7a7a\u95f4\u4e2d\uff0c\u5728\u6570\u636e\u5e93\u4e2d\u53ef\u4ee5\u5b58\u5728\u591a\u4e2aundo\u8868\u7a7a\u95f4\uff0c\u4f46\u540c\u4e00\u65f6\u523b\u53ea\u80fd\u4f7f\u7528\u4e00\u4e2aundo\u8868\u7a7a\u95f4\u3002\r\n\r\n# 5. \u5f53\u4e8b\u52a1\u63d0\u4ea4\u65f6\uff0cInnoDB\u5b58\u50a8\u5f15\u64ce\u4f1a\u505a\u4ee5\u4e0b\u4e24\u4ef6\u4e8b\u60c5\uff1a\r\n#     \u5c06undo log\u653e\u5165\u5217\u8868\u4e2d\uff0c\u4ee5\u4f9b\u4e4b\u540e\u7684purge\u64cd\u4f5c\r\n#     \u5224\u65adundo log\u6240\u5728\u7684\u9875\u662f\u5426\u53ef\u4ee5\u91cd\u7528\uff0c\u82e5\u53ef\u4ee5\u5206\u914d\u7ed9\u4e0b\u4e2a\u4e8b\u52a1\u4f7f\u7528\r\n\r\n# 3. \u56de\u6eda\u6bb5\u4e2d\u7684\u6570\u636e\u5206\u7c7b\r\n# 1. \u672a\u63d0\u4ea4\u7684\u56de\u6eda\u6570\u636e(uncommitted undo information)\r\n# 2. \u5df2\u7ecf\u63d0\u4ea4\u4f46\u672a\u8fc7\u671f\u7684\u56de\u6eda\u6570\u636e(committed undo information)\r\n# 3. \u4e8b\u52a1\u5df2\u7ecf\u63d0\u4ea4\u5e76\u8fc7\u671f\u7684\u6570\u636e(expired undo information)\r\n\r\n# 2.4 undo\u7684\u7c7b\u578b\r\n# \u5728InnoDB\u5b58\u50a8\u5f15\u64ce\u4e2d\uff0cundo log\u5206\u4e3a\uff1a\r\n# insert undo log\r\n# update undo log\r\n\r\n# 2.5 undo log\u7684\u751f\u547d\u5468\u671f\r\n\r\n# 4. undo log\u7684\u5220\u9664\r\n# \u9488\u5bf9\u4e8einsert undo log\r\n# \u56e0\u4e3ainsert\u64cd\u4f5c\u7684\u8bb0\u5f55\uff0c\u53ea\u5bf9\u4e8b\u52a1\u672c\u8eab\u53ef\u89c1\uff0c\u5bf9\u5176\u4ed6\u4e8b\u52a1\u4e0d\u53ef\u89c1\u3002\u6545\u8be5undo log\u53ef\u4ee5\u5728\u4e8b\u52a1\u63d0\u4ea4\u540e\u76f4\u63a5\u5220\u9664\uff0c\r\n# \u4e0d\u9700\u8981\u8fdb\u884cpurge\u64cd\u4f5c\u3002\r\n\r\n# \u9488\u5bf9\u4e8eupdate undo log\r\n# \u8be5undo log\u53ef\u80fd\u9700\u8981\u63d0\u4f9bMVCC\u673a\u5236\uff0c\u56e0\u6b64\u4e0d\u80fd\u5728\u4e8b\u52a1\u63d0\u4ea4\u65f6\u5c31\u8fdb\u884c\u5220\u9664\u3002\u63d0\u4ea4\u65f6\u653e\u5165undo log\u94fe\u8868\uff0c\r\n# \u7b49\u5f85purge\u7ebf\u7a0b\u8fdb\u884c\u6700\u540e\u7684\u5220\u9664\u3002\r\n\r\n# 2.6 \u5c0f\u7ed3\r\n\r\n# undo log\u662f\u903b\u8f91\u65e5\u5fd7\uff0c\u5bf9\u4e8b\u52a1\u56de\u6eda\u65f6\uff0c\u53ea\u662f\u5c06\u6570\u636e\u5e93\u903b\u8f91\u5730\u6062\u590d\u5230\u539f\u6765\u7684\u6837\u5b50\u3002\r\n\r\n# redo log\u662f\u7269\u7406\u65e5\u5fd7\uff0c\u8bb0\u5f55\u7684\u662f\u6570\u636e\u9875\u7684\u7269\u7406\u53d8\u5316\uff0cundo log\u4e0d\u662fredo log\u7684\u9006\u8fc7\u7a0b\u3002\r\n\r\n\r\n<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2.5 undo log\u7684\u751f\u547d\u5468\u671f<\/h3>\n\n\n\n<p>\u53ea\u6709Buffer Pool\u7684\u6d41\u7a0b<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/qaqaq.top\/wp-content\/uploads\/2022\/11\/\u53ea\u6709Buffer-Pool\u7684\u6d41\u7a0b.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"816\" height=\"343\" data-original=\"https:\/\/qaqaq.top\/wp-content\/uploads\/2022\/11\/\u53ea\u6709Buffer-Pool\u7684\u6d41\u7a0b.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-1681\"  sizes=\"(max-width: 816px) 100vw, 816px\" \/><\/div><\/figure>\n\n\n\n<p>\u6709\u4e86Redo Log\u548cUndo Log\u4e4b\u540e<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/qaqaq.top\/wp-content\/uploads\/2022\/11\/\u6709\u4e86Redo-Log\u548cUndo-Log\u4e4b\u540e-1024x547.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"547\" data-original=\"https:\/\/qaqaq.top\/wp-content\/uploads\/2022\/11\/\u6709\u4e86Redo-Log\u548cUndo-Log\u4e4b\u540e-1024x547.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-1682\"  sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>2.5 undo log\u7684\u751f\u547d\u5468\u671f \u53ea\u6709Buffer Pool\u7684\u6d41\u7a0b \u6709\u4e86Redo Log\u548cUndo Log\u4e4b [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[47],"class_list":["post-1680","post","type-post","status-publish","format-standard","hentry","category-mysql-code","tag-mysql"],"_links":{"self":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1680"}],"collection":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1680"}],"version-history":[{"count":1,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1680\/revisions"}],"predecessor-version":[{"id":1683,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1680\/revisions\/1683"}],"wp:attachment":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1680"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1680"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1680"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}