{"id":209776,"date":"2022-08-18T16:01:19","date_gmt":"2022-08-18T08:01:19","guid":{"rendered":"https:\/\/www.keaglegz.com\/209776.html"},"modified":"2022-08-18T16:01:19","modified_gmt":"2022-08-18T08:01:19","slug":"mysql%e7%9a%84undo-log%e5%92%8credo-log","status":"publish","type":"post","link":"https:\/\/www.dongwubaike.cn\/fanhao\/209776.html","title":{"rendered":"MySQL\u7684undo log\u548credo log"},"content":{"rendered":"\n

\u5728\u6570\u636e\u5e93\u7cfb\u7edf\u4e2d\uff0c\u65e2\u6709\u5b58\u653e\u6570\u636e\u7684\u6587\u4ef6\uff0c\u4e5f\u6709\u5b58\u653e\u65e5\u5fd7\u7684\u6587\u4ef6\u3002\u65e5\u5fd7\u5728\u5185\u5b58\u4e2d\u4e5f\u662f\u6709\u7f13\u5b58Log buffer\uff0c\u4e5f\u6709\u78c1\u76d8\u6587\u4ef6log file\uff0c\u672c\u6587\u4e3b\u8981\u63cf\u8ff0\u5b58\u653e\u65e5\u5fd7\u7684\u6587\u4ef6\u3002<\/p>\n

MySQL\u4e2d\u7684\u65e5\u5fd7\u6587\u4ef6\uff0c\u6709\u8fd9\u4e48\u4e24\u7c7b\u5e38\u5e38\u8ba8\u8bba\u5230\uff1aundo\u65e5\u5fd7\u4e0eredo\u65e5\u5fd7\u3002<\/div>\n

1 undo<\/strong><\/h2>\n

1.1 undo\u662f\u4ec0\u4e48<\/strong><\/h3>\n
undo\u65e5\u5fd7\u7528\u4e8e\u5b58\u653e\u6570\u636e\u4fee\u6539\u88ab\u4fee\u6539\u524d\u7684\u503c\uff0c\u5047\u8bbe\u4fee\u6539 tba \u8868\u4e2d id=2\u7684\u884c\u6570\u636e\uff0c\u628aName=’B’ \u4fee\u6539\u4e3aName = ‘B2’ \uff0c\u90a3\u4e48undo\u65e5\u5fd7\u5c31\u4f1a\u7528\u6765\u5b58\u653eName=’B’\u7684\u8bb0\u5f55\uff0c\u5982\u679c\u8fd9\u4e2a\u4fee\u6539\u51fa\u73b0\u5f02\u5e38\uff0c\u53ef\u4ee5\u4f7f\u7528undo\u65e5\u5fd7\u6765\u5b9e\u73b0\u56de\u6eda\u64cd\u4f5c\uff0c\u4fdd\u8bc1\u4e8b\u52a1\u7684\u4e00\u81f4\u6027\u3002<\/div>\n
\u5bf9\u6570\u636e\u7684\u53d8\u66f4\u64cd\u4f5c\uff0c\u4e3b\u8981\u6765\u81ea INSERT UPDATE DELETE\uff0c\u800cUNDO LOG\u4e2d\u5206\u4e3a\u4e24\u79cd\u7c7b\u578b\uff0c\u4e00\u79cd\u662f INSERT_UNDO\uff08INSERT\u64cd\u4f5c\uff09\uff0c\u8bb0\u5f55\u63d2\u5165\u7684\u552f\u4e00\u952e\u503c\uff1b\u4e00\u79cd\u662f UPDATE_UNDO\uff08\u5305\u542bUPDATE\u53caDELETE\u64cd\u4f5c\uff09\uff0c\u8bb0\u5f55\u4fee\u6539\u7684\u552f\u4e00\u952e\u503c\u4ee5\u53caold column\u8bb0\u5f55\u3002<\/div>\n\n\n\n\n\n\n\n
Id<\/td>\nName<\/td>\n<\/tr>\n
1<\/td>\nA<\/td>\n<\/tr>\n
2<\/td>\nB<\/td>\n<\/tr>\n
3<\/td>\nC<\/td>\n<\/tr>\n
4<\/td>\n\n
D<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

1.2 undo\u53c2\u6570<\/strong><\/h3>\n
MySQL\u8ddfundo\u6709\u5173\u7684\u53c2\u6570\u8bbe\u7f6e\u6709\u8fd9\u4e9b\uff1a<\/div>\n

mysql> show global variables like ‘%undo%’;
+————————–+————+
| Variable_name            | Value      |
+————————–+————+
| innodb_max_undo_log_size | 1073741824 |
| innodb_undo_directory    | .\/        |
| innodb_undo_log_truncate | OFF        |
| innodb_undo_logs        | 128        |
| innodb_undo_tablespaces  | 3          |
+————————–+————+
 
mysql> show global variables like ‘%truncate%’;
+————————————–+——-+
| Variable_name                        | Value |
+————————————–+——-+
| innodb_purge_rseg_truncate_frequency | 128  |
| innodb_undo_log_truncate            | OFF  |
+————————————–+——-+<\/p>\n

innodb_max_undo_log_size<\/strong><\/p>\n

    \u63a7\u5236\u6700\u5927undo tablespace\u6587\u4ef6\u7684\u5927\u5c0f\uff0c\u5f53\u542f\u52a8\u4e86innodb_undo_log_truncate \u65f6\uff0cundo tablespace \u8d85\u8fc7innodb_max_undo_log_size \u9600\u503c\u65f6\u624d\u4f1a\u53bb\u5c1d\u8bd5truncate\u3002\u8be5\u503c\u9ed8\u8ba4\u5927\u5c0f\u4e3a1G\uff0ctruncate\u540e\u7684\u5927\u5c0f\u9ed8\u8ba4\u4e3a10M\u3002<\/div>\n
\n
    \n
  • innodb_undo_tablespaces<\/strong> <\/li>\n<\/ul><\/div>\n
        \u8bbe\u7f6eundo\u72ec\u7acb\u8868\u7a7a\u95f4\u4e2a\u6570\uff0c\u8303\u56f4\u4e3a0-128\uff0c \u9ed8\u8ba4\u4e3a0\uff0c0\u8868\u793a\u8868\u793a\u4e0d\u5f00\u542f\u72ec\u7acbundo\u8868\u7a7a\u95f4 \u4e14 undo\u65e5\u5fd7\u5b58\u50a8\u5728ibdata\u6587\u4ef6\u4e2d\u3002\u8be5\u53c2\u6570\u53ea\u80fd\u5728\u6700\u5f00\u59cb\u521d\u59cb\u5316MySQL\u5b9e\u4f8b\u7684\u65f6\u5019\u6307\u5b9a\uff0c\u5982\u679c\u5b9e\u4f8b\u5df2\u521b\u5efa\uff0c\u8fd9\u4e2a\u53c2\u6570\u662f\u4e0d\u80fd\u53d8\u52a8\u7684\uff0c\u5982\u679c\u5728\u6570\u636e\u5e93\u914d\u7f6e\u6587 \u4ef6 .cnf \u4e2d\u6307\u5b9ainnodb_undo_tablespaces \u7684\u4e2a\u6570\u5927\u4e8e\u5b9e\u4f8b\u521b\u5efa\u65f6\u7684\u6307\u5b9a\u4e2a\u6570\uff0c\u5219\u4f1a\u542f\u52a8\u5931\u8d25\uff0c\u63d0\u793a\u8be5\u53c2\u6570\u8bbe\u7f6e\u6709\u8bef\u3002<\/div>\n
    \"MySQL\u7684undo<\/div>\n
        \u5982\u679c\u8bbe\u7f6e\u4e86\u8be5\u53c2\u6570\u4e3an\uff08n>0\uff09\uff0c\u90a3\u4e48\u5c31\u4f1a\u5728undo\u76ee\u5f55\u4e0b\u521b\u5efan\u4e2aundo\u6587\u4ef6\uff08undo001\uff0cundo002 …… undo n\uff09\uff0c\u6bcf\u4e2a\u6587\u4ef6\u9ed8\u8ba4\u5927\u5c0f\u4e3a10M.<\/div>\n
    \"MySQL\u7684undo<\/div>\n
    \u4ec0\u4e48\u65f6\u5019\u9700\u8981\u6765\u8bbe\u7f6e\u8fd9\u4e2a\u53c2\u6570\u5462\uff1f<\/strong><\/div>\n
        \u5f53DB\u5199\u538b\u529b\u8f83\u5927\u65f6\uff0c\u53ef\u4ee5\u8bbe\u7f6e\u72ec\u7acbUNDO\u8868\u7a7a\u95f4\uff0c\u628aUNDO LOG\u4eceibdata\u6587\u4ef6\u4e2d\u5206\u79bb\u5f00\u6765\uff0c\u6307\u5b9a innodb_undo_directory\u76ee\u5f55\u5b58\u653e\uff0c\u53ef\u4ee5\u5236\u5b9a\u5230\u9ad8\u901f\u78c1\u76d8\u4e0a\uff0c\u52a0\u5febUNDO LOG \u7684\u8bfb\u5199\u6027\u80fd\u3002<\/div>\n
    \n
      \n
    • innodb_undo_log_truncate<\/strong><\/li>\n<\/ul><\/div>\n
        InnoDB\u7684purge\u7ebf\u7a0b\uff0c\u6839\u636einnodb_undo_log_truncate\u8bbe\u7f6e\u5f00\u542f\u6216\u5173\u95ed\u3001innodb_max_undo_log_size\u7684\u53c2\u6570\u503c\uff0c\u4ee5\u53catruncate\u7684\u9891\u7387\u6765\u8fdb\u884c\u7a7a\u95f4\u56de\u6536\u548c undo file \u7684\u91cd\u65b0\u521d\u59cb\u5316\u3002<\/div>\n
        \u8be5\u53c2\u6570\u751f\u6548\u7684\u524d\u63d0\u662f\uff0c\u5df2\u8bbe\u7f6e\u72ec\u7acb\u8868\u7a7a\u95f4\u4e14\u72ec\u7acb\u8868\u7a7a\u95f4\u4e2a\u6570\u5927\u4e8e\u7b49\u4e8e2\u4e2a\u3002<\/strong><\/div>\n
        purge\u7ebf\u7a0b\u5728truncate undo log file\u7684\u8fc7\u7a0b\u4e2d\uff0c\u9700\u8981\u68c0\u67e5\u8be5\u6587\u4ef6\u4e0a\u662f\u5426\u8fd8\u6709\u6d3b\u52a8\u4e8b\u52a1\uff0c\u5982\u679c\u6ca1\u6709\uff0c\u9700\u8981\u628a\u8be5undo log file\u6807\u8bb0\u4e3a\u4e0d\u53ef\u5206\u914d\uff0c\u8fd9\u4e2a\u65f6\u5019\uff0cundo log \u90fd\u4f1a\u8bb0\u5f55\u5230\u5176\u4ed6\u6587\u4ef6\u4e0a\uff0c\u6240\u4ee5\u81f3\u5c11\u9700\u89812\u4e2a\u72ec\u7acb\u8868\u7a7a\u95f4\u6587\u4ef6\uff0c\u624d\u80fd\u8fdb\u884ctruncate \u64cd\u4f5c\uff0c\u6807\u6ce8\u4e0d\u53ef\u5206\u914d\u540e\uff0c\u4f1a\u521b\u5efa\u4e00\u4e2a\u72ec\u7acb\u7684\u6587\u4ef6undo_<space_id>_trunc.log\uff0c\u8bb0\u5f55\u73b0\u5728\u6b63\u5728truncate \u67d0\u4e2aundo log\u6587\u4ef6\uff0c\u7136\u540e\u5f00\u59cb\u521d\u59cb\u5316undo log file\u523010M\uff0c\u64cd\u4f5c\u7ed3\u675f\u540e\uff0c\u5220\u9664\u8868\u793atruncate\u52a8\u4f5c\u7684 undo_<space_id>_trunc.log \u6587\u4ef6\uff0c\u8fd9\u4e2a\u6587\u4ef6\u4fdd\u8bc1\u4e86\u5373\u4f7f\u5728truncate\u8fc7\u7a0b\u4e2d\u53d1\u751f\u4e86\u6545\u969c\u91cd\u542f\u6570\u636e\u5e93\u670d\u52a1\uff0c\u91cd\u542f\u540e\uff0c\u670d\u52a1\u53d1\u73b0\u8fd9\u4e2a\u6587\u4ef6\uff0c\u4e5f\u4f1a\u7ee7\u7eed\u5b8c\u6210truncate\u64cd\u4f5c\uff0c\u5220\u9664\u6587\u4ef6\u7ed3\u675f\u540e\uff0c\u6807\u8bc6\u8be5undo log file\u53ef\u5206\u914d\u3002<\/div>\n
      \n
        \n
      • innodb_purge_rseg_truncate_frequency<\/strong><\/li>\n<\/ul><\/div>\n
          \u7528\u4e8e\u63a7\u5236purge\u56de\u6eda\u6bb5\u7684\u9891\u5ea6\uff0c\u9ed8\u8ba4\u4e3a128\u3002\u5047\u8bbe\u8bbe\u7f6e\u4e3an\uff0c\u5219\u8bf4\u660e\uff0c\u5f53Innodb Purge\u64cd\u4f5c\u7684\u534f\u8c03\u7ebf\u7a0b purge\u4e8b\u52a1128\u6b21\u65f6\uff0c\u5c31\u4f1a\u89e6\u53d1\u4e00\u6b21History purge\uff0c\u68c0\u67e5\u5f53\u524d\u7684undo log \u8868\u7a7a\u95f4\u72b6\u6001\u662f\u5426\u4f1a\u89e6\u53d1truncate\u3002<\/div>\n

        1.3 undo\u7a7a\u95f4\u7ba1\u7406<\/strong><\/h3>\n
        \u5982\u679c\u9700\u8981\u8bbe\u7f6e\u72ec\u7acb\u8868\u7a7a\u95f4\uff0c\u9700\u8981\u5728\u521d\u59cb\u5316\u6570\u636e\u5e93\u5b9e\u4f8b\u7684\u65f6\u5019\uff0c\u6307\u5b9a\u72ec\u7acb\u8868\u7a7a\u95f4\u7684\u6570\u91cf\u3002<\/div>\n
        UNDO\u5185\u90e8\u7531\u591a\u4e2a\u56de\u6eda\u6bb5\u7ec4\u6210\uff0c\u5373 Rollback segment\uff0c\u4e00\u5171\u6709128\u4e2a\uff0c\u4fdd\u5b58\u5728ibdata\u7cfb\u7edf\u8868\u7a7a\u95f4\u4e2d\uff0c\u5206\u522b\u4eceresg slot0 – resg slot127\uff0c\u6bcf\u4e00\u4e2aresg slot\uff0c\u4e5f\u5c31\u662f\u6bcf\u4e00\u4e2a\u56de\u6eda\u6bb5\uff0c\u5185\u90e8\u75311024\u4e2aundo segment \u7ec4\u6210\u3002<\/div>\n
        \u56de\u6eda\u6bb5\uff08rollback segment\uff09\u5206\u914d\u5982\u4e0b\uff1a<\/div>\n
          \n
        • slot 0 \uff0c\u9884\u7559\u7ed9\u7cfb\u7edf\u8868\u7a7a\u95f4\uff1b<\/li>\n
        • slot 1- 32\uff0c\u9884\u7559\u7ed9\u4e34\u65f6\u8868\u7a7a\u95f4\uff0c\u6bcf\u6b21\u6570\u636e\u5e93\u91cd\u542f\u7684\u65f6\u5019\uff0c\u90fd\u4f1a\u91cd\u5efa\u4e34\u65f6\u8868\u7a7a\u95f4\uff1b<\/li>\n
        • slot33-127\uff0c\u5982\u679c\u6709\u72ec\u7acb\u8868\u7a7a\u95f4\uff0c\u5219\u9884\u7559\u7ed9UNDO\u72ec\u7acb\u8868\u7a7a\u95f4\uff1b\u5982\u679c\u6ca1\u6709\uff0c\u5219\u9884\u7559\u7ed9\u7cfb\u7edf\u8868\u7a7a\u95f4\uff1b<\/li>\n<\/ul>\n
          \u56de\u6eda\u6bb5\u4e2d\u9664\u53bb32\u4e2a\u63d0\u4f9b\u7ed9\u4e34\u65f6\u8868\u4e8b\u52a1\u4f7f\u7528\uff0c\u5269\u4e0b\u7684 128-32=96\u4e2a\u56de\u6eda\u6bb5\uff0c\u53ef\u6267\u884c 96*1024 \u4e2a\u5e76\u53d1\u4e8b\u52a1\u64cd\u4f5c\uff0c\u6bcf\u4e2a\u4e8b\u52a1\u5360\u7528\u4e00\u4e2a undo segment slot\uff0c\u6ce8\u610f\uff0c\u5982\u679c\u4e8b\u52a1\u4e2d\u6709\u4e34\u65f6\u8868\u4e8b\u52a1\uff0c\u8fd8\u4f1a\u5728\u4e34\u65f6\u8868\u7a7a\u95f4\u4e2d\u7684 undo segment slot \u518d\u5360\u7528\u4e00\u4e2a undo segment slot\uff0c\u5373\u5360\u75282\u4e2aundo segment slot\u3002\u5982\u679c\u9519\u8bef\u65e5\u5fd7\u4e2d\u6709\uff1aCannot find a free slot for an undo log\u3002<\/code>\u5219\u8bf4\u660e\u5e76\u53d1\u7684\u4e8b\u52a1\u592a\u591a\u4e86\uff0c\u9700\u8981\u8003\u8651\u4e0b\u662f\u5426\u8981\u5206\u6d41\u4e1a\u52a1\u3002<\/div>\n
          \u56de\u6eda\u6bb5\uff08rollback segment \uff09\u91c7\u7528 \u8f6e\u8be2\u8c03\u5ea6\u7684\u65b9\u5f0f\u6765\u5206\u914d\u4f7f\u7528\uff0c\u5982\u679c\u8bbe\u7f6e\u4e86\u72ec\u7acb\u8868\u7a7a\u95f4\uff0c\u90a3\u4e48\u5c31\u4e0d\u4f1a\u4f7f\u7528\u7cfb\u7edf\u8868\u7a7a\u95f4\u56de\u6eda\u6bb5\u4e2dundo segment\uff0c\u800c\u662f\u4f7f\u7528\u72ec\u7acb\u8868\u7a7a\u95f4\u7684\uff0c\u540c\u65f6\uff0c\u5982\u679c\u56de\u987e\u6bb5\u6b63\u5728 Truncate\u64cd\u4f5c\uff0c\u5219\u4e0d\u5206\u914d\u3002<\/div>\n
          \"MySQL\u7684undo<\/div>\n

          2 redo<\/strong><\/h2>\n

          2.1 redo\u662f\u4ec0\u4e48<\/strong><\/h3>\n
              \u5f53\u6570\u636e\u5e93\u5bf9\u6570\u636e\u505a\u4fee\u6539\u7684\u65f6\u5019\uff0c\u9700\u8981\u628a\u6570\u636e\u9875\u4ece\u78c1\u76d8\u8bfb\u5230buffer pool\u4e2d\uff0c\u7136\u540e\u5728buffer pool\u4e2d\u8fdb\u884c\u4fee\u6539\uff0c\u90a3\u4e48\u8fd9\u4e2a\u65f6\u5019buffer pool\u4e2d\u7684\u6570\u636e\u9875\u5c31\u4e0e\u78c1\u76d8\u4e0a\u7684\u6570\u636e\u9875\u5185\u5bb9\u4e0d\u4e00\u81f4\uff0c\u79f0buffer pool\u7684\u6570\u636e\u9875\u4e3adirty page \u810f\u6570\u636e\uff0c\u5982\u679c\u8fd9\u4e2a\u65f6\u5019\u53d1\u751f\u975e\u6b63\u5e38\u7684DB\u670d\u52a1\u91cd\u542f\uff0c\u90a3\u4e48\u8fd9\u4e9b\u6570\u636e\u8fd8\u6ca1\u5728\u5185\u5b58\uff0c\u5e76\u6ca1\u6709\u540c\u6b65\u5230\u78c1\u76d8\u6587\u4ef6\u4e2d\uff08\u6ce8\u610f\uff0c\u540c\u6b65\u5230\u78c1\u76d8\u6587\u4ef6\u662f\u4e2a\u968f\u673aIO\uff09\uff0c\u4e5f\u5c31\u662f\u4f1a\u53d1\u751f\u6570\u636e\u4e22\u5931\uff0c\u5982\u679c\u8fd9\u4e2a\u65f6\u5019\uff0c\u80fd\u591f\u5728\u6709\u4e00\u4e2a\u6587\u4ef6\uff0c\u5f53buffer pool \u4e2d\u7684data page\u53d8\u66f4\u7ed3\u675f\u540e\uff0c\u628a\u76f8\u5e94\u4fee\u6539\u8bb0\u5f55\u8bb0\u5f55\u5230\u8fd9\u4e2a\u6587\u4ef6\uff08\u6ce8\u610f\uff0c\u8bb0\u5f55\u65e5\u5fd7\u662f\u987a\u5e8fIO\uff09\uff0c\u90a3\u4e48\u5f53DB\u670d\u52a1\u53d1\u751fcrash\u7684\u60c5\u51b5\uff0c\u6062\u590dDB\u7684\u65f6\u5019\uff0c\u4e5f\u53ef\u4ee5\u6839\u636e\u8fd9\u4e2a\u6587\u4ef6\u7684\u8bb0\u5f55\u5185\u5bb9\uff0c\u91cd\u65b0\u5e94\u7528\u5230\u78c1\u76d8\u6587\u4ef6\uff0c\u6570\u636e\u4fdd\u6301\u4e00\u81f4\u3002<\/div>\n
              \u8fd9\u4e2a\u6587\u4ef6\u5c31\u662fredo log \uff0c\u7528\u4e8e\u8bb0\u5f55 \u6570\u636e\u4fee\u6539\u540e\u7684\u8bb0\u5f55\uff0c\u987a\u5e8f\u8bb0\u5f55\u3002\u5b83\u53ef\u4ee5\u5e26\u6765\u8fd9\u4e9b\u597d\u5904\uff1a<\/div>\n
            \n
          • \u5f53buffer pool\u4e2d\u7684dirty page \u8fd8\u6ca1\u6709\u5237\u65b0\u5230\u78c1\u76d8\u7684\u65f6\u5019\uff0c\u53d1\u751fcrash\uff0c\u542f\u52a8\u670d\u52a1\u540e\uff0c\u53ef\u901a\u8fc7redo log \u627e\u5230\u9700\u8981\u91cd\u65b0\u5237\u65b0\u5230\u78c1\u76d8\u6587\u4ef6\u7684\u8bb0\u5f55\uff1b<\/li>\n
          • buffer pool\u4e2d\u7684\u6570\u636e\u76f4\u63a5flush\u5230disk file\uff0c\u662f\u4e00\u4e2a\u968f\u673aIO\uff0c\u6548\u7387\u8f83\u5dee\uff0c\u800c\u628abuffer pool\u4e2d\u7684\u6570\u636e\u8bb0\u5f55\u5230redo log\uff0c\u662f\u4e00\u4e2a\u987a\u5e8fIO\uff0c\u53ef\u4ee5\u63d0\u9ad8\u4e8b\u52a1\u63d0\u4ea4\u7684\u901f\u5ea6\uff1b<\/li>\n<\/ul>\n
                \u5047\u8bbe\u4fee\u6539 tba \u8868\u4e2d id=2\u7684\u884c\u6570\u636e\uff0c\u628aName=’B’ \u4fee\u6539\u4e3aName = ‘B2’ \uff0c\u90a3\u4e48redo\u65e5\u5fd7\u5c31\u4f1a\u7528\u6765\u5b58\u653eName=’B2’\u7684\u8bb0\u5f55\uff0c\u5982\u679c\u8fd9\u4e2a\u4fee\u6539\u5728flush \u5230\u78c1\u76d8\u6587\u4ef6\u65f6\u51fa\u73b0\u5f02\u5e38\uff0c\u53ef\u4ee5\u4f7f\u7528redo log\u5b9e\u73b0\u91cd\u505a\u64cd\u4f5c\uff0c\u4fdd\u8bc1\u4e8b\u52a1\u7684\u6301\u4e45\u6027\u3002<\/div>\n\n\n\n\n\n\n\n
            Id<\/td>\nName<\/td>\n<\/tr>\n
            1<\/td>\nA<\/td>\n<\/tr>\n
            2<\/td>\nB<\/td>\n<\/tr>\n
            3<\/td>\nC<\/td>\n<\/tr>\n
            4<\/td>\n\n
            D<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
             <\/div>\n
                \u8fd9\u91cc\u6ce8\u610f\u4e0bredo log \u8ddfbinary log \u7684\u533a\u522b\uff0credo log \u662f\u5b58\u50a8\u5f15\u64ce\u5c42\u4ea7\u751f\u7684\uff0c\u800cbinary log\u662f\u6570\u636e\u5e93\u5c42\u4ea7\u751f\u7684\u3002\u5047\u8bbe\u4e00\u4e2a\u5927\u4e8b\u52a1\uff0c\u5bf9tba\u505a10\u4e07\u884c\u7684\u8bb0\u5f55\u63d2\u5165\uff0c\u5728\u8fd9\u4e2a\u8fc7\u7a0b\u4e2d\uff0c\u4e00\u76f4\u4e0d\u65ad\u7684\u5f80redo log\u987a\u5e8f\u8bb0\u5f55\uff0c\u800cbinary log\u4e0d\u4f1a\u8bb0\u5f55\uff0c\u77e5\u9053\u8fd9\u4e2a\u4e8b\u52a1\u63d0\u4ea4\uff0c\u624d\u4f1a\u4e00\u6b21\u5199\u5165\u5230binary log\u6587\u4ef6\u4e2d\u3002binary log\u7684\u8bb0\u5f55\u683c\u5f0f\u67093\u79cd\uff1arow\uff0cstatement\u8ddfmixed\uff0c\u4e0d\u540c\u683c\u5f0f\u8bb0\u5f55\u5f62\u5f0f\u4e0d\u4e00\u6837\u3002<\/div>\n

            2.2<\/strong> redo<\/strong> \u53c2\u6570<\/strong><\/h3>\n
            \n
              \n
            • innodb_log_files_in_group<\/strong><\/li>\n<\/ul><\/div>\n
              redo log \u6587\u4ef6\u7684\u4e2a\u6570\uff0c\u547d\u540d\u65b9\u5f0f\u5982\uff1aib_logfile0\uff0ciblogfile1… iblogfilen\u3002\u9ed8\u8ba42\u4e2a\uff0c\u6700\u5927100\u4e2a\u3002<\/div>\n
              \n
                \n
              • innodb_log_file_size<\/strong><\/li>\n<\/ul><\/div>\n
                \u6587\u4ef6\u8bbe\u7f6e\u5927\u5c0f\uff0c\u9ed8\u8ba4\u503c\u4e3a 48M\uff0c\u6700\u5927\u503c\u4e3a512G\uff0c\u6ce8\u610f\u6700\u5927\u503c\u6307\u7684\u662f\u6574\u4e2a redo log\u7cfb\u5217\u6587\u4ef6\u4e4b\u548c\uff0c\u5373\uff08innodb_log_files_in_group * innodb_log_file_size \uff09\u4e0d\u80fd\u5927\u4e8e\u6700\u5927\u503c512G\u3002<\/div>\n
                \n
                  \n
                • innodb_log_group_home_dir<\/strong><\/li>\n<\/ul><\/div>\n
                  \u6587\u4ef6\u5b58\u653e\u8def\u5f84<\/div>\n
                  \n
                    \n
                  • innodb_log_buffer_size<\/strong><\/li>\n<\/ul><\/div>\n
                    Redo Log \u7f13\u5b58\u533a\uff0c\u9ed8\u8ba48M\uff0c\u53ef\u8bbe\u7f6e1-8M\u3002\u5ef6\u8fdf\u4e8b\u52a1\u65e5\u5fd7\u5199\u5165\u78c1\u76d8\uff0c\u628aredo log \u653e\u5230\u8be5\u7f13\u51b2\u533a\uff0c\u7136\u540e\u6839\u636e innodb_flush_log_at_trx_commit\u53c2\u6570\u7684\u8bbe\u7f6e\uff0c\u518d\u628a\u65e5\u5fd7\u4ecebuffer \u4e2dflush \u5230\u78c1\u76d8\u4e2d\u3002<\/div>\n
                    \n
                      \n
                    • innodb_flush_log_at_trx_commit<\/strong><\/li>\n<\/ul><\/div>\n
                        \n
                      • innodb_flush_log_at_trx_commit=1\uff0c\u6bcf\u6b21commit\u90fd\u4f1a\u628aredo log\u4eceredo log buffer\u5199\u5165\u5230system\uff0c\u5e76fsync\u5237\u65b0\u5230\u78c1\u76d8\u6587\u4ef6\u4e2d\u3002<\/li>\n
                      • innodb_flush_log_at_trx_commit=2\uff0c\u6bcf\u6b21\u4e8b\u52a1\u63d0\u4ea4\u65f6MySQL\u4f1a\u628a\u65e5\u5fd7\u4eceredo log buffer\u5199\u5165\u5230system\uff0c\u4f46\u53ea\u5199\u5165\u5230file system buffer\uff0c\u7531\u7cfb\u7edf\u5185\u90e8\u6765fsync\u5230\u78c1\u76d8\u6587\u4ef6\u3002\u5982\u679c\u6570\u636e\u5e93\u5b9e\u4f8bcrash\uff0c\u4e0d\u4f1a\u4e22\u5931redo log\uff0c\u4f46\u662f\u5982\u679c\u670d\u52a1\u5668crash\uff0c\u7531\u4e8efile system buffer\u8fd8\u6765\u4e0d\u53cafsync\u5230\u78c1\u76d8\u6587\u4ef6\uff0c\u6240\u4ee5\u4f1a\u4e22\u5931\u8fd9\u4e00\u90e8\u5206\u7684\u6570\u636e\u3002<\/li>\n
                      • innodb_flush_log_at_trx_commit=0\uff0c\u4e8b\u52a1\u53d1\u751f\u8fc7\u7a0b\uff0c\u65e5\u5fd7\u4e00\u76f4\u6fc0\u52b1\u5728redo log buffer\u4e2d\uff0c\u8ddf\u5176\u4ed6\u8bbe\u7f6e\u4e00\u6837\uff0c\u4f46\u662f\u5728\u4e8b\u52a1\u63d0\u4ea4\u65f6\uff0c\u4e0d\u4ea7\u751fredo \u5199\u64cd\u4f5c\uff0c\u800c\u662fMySQL\u5185\u90e8\u6bcf\u79d2\u64cd\u4f5c\u4e00\u6b21\uff0c\u4eceredo log buffer\uff0c\u628a\u6570\u636e\u5199\u5165\u5230\u7cfb\u7edf\u4e2d\u53bb\u3002\u5982\u679c\u53d1\u751fcrash\uff0c\u5373\u4e22\u59311s\u5185\u7684\u4e8b\u52a1\u4fee\u6539\u64cd\u4f5c\u3002<\/li>\n<\/ul>\n
                        \n