MySQL主库binlog(masterlog)与从库relaylog关系代码详解

数据运维 2023-04-28 LOVEHL^ˇ^ 手机阅读

主库binlog: # at 2420#170809 17:16:20 server id 1882073306 end_log_pos 2451 CRC32 0x58f2db87 Xid = 32880COMMIT/!/;# at 2451#170814 11:07:18 server id 1882073306 end_log_pos 2528 CRC32 0x40774a4b Query thread_id=92 exec_time=0 error_code

                        <p>主库binlog:</p>
  1. at 2420 #170809 17:16:20 server id 1882073306 end_log_pos 2451 CRC32 0x58f2db87 Xid = 32880 COMMIT/!/;
  2. at 2451 #170814 11:07:18 server id 1882073306 end_log_pos 2528 CRC32 0x40774a4b Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680038/!/; BEGIN /!/;
  3. at 2528
  4. at 2560 #170814 11:07:18 server id 1882073306 end_log_pos 2560 CRC32 0x7bdf274b Intvar SET INSERT_ID=107/!/; #170814 11:07:18 server id 1882073306 end_log_pos 2669 CRC32 0x68e441c8 Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680038/!/; insert into t2 (name) values ('a100') /!/;
  5. at 2669
  6. at 2701 #170814 11:07:27 server id 1882073306 end_log_pos 2701 CRC32 0xcf89b910 Intvar SET INSERT_ID=108/!/; #170814 11:07:27 server id 1882073306 end_log_pos 2810 CRC32 0x78466d7b Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680047/!/; insert into t2 (name) values ('a200') /!/;
  7. at 2810
  8. at 2842 #170814 11:07:30 server id 1882073306 end_log_pos 2842 CRC32 0x1e5a0847 Intvar SET INSERT_ID=109/!/; #170814 11:07:30 server id 1882073306 end_log_pos 2951 CRC32 0xebeb947c Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680050/!/; insert into t2 (name) values ('a300') /!/;
  9. at 2951 #170814 11:07:34 server id 1882073306 end_log_pos 2982 CRC32 0x6436ad60 Xid = 32934 COMMIT/!/;

从库relay-log:

/!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1/; /!40019 SET @@session.max_insert_delayed_threads=0/; /!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0/; DELIMITER /!/;

  1. at 4 #170809 17:17:24 server id 1882083306 end_log_pos 120 CRC32 0x5df4221c Start: binlog v 4, server v 5.6.23-72.1-log created 170809 17:17:24
  2. at 120 #700101 8:00:00 server id 1882073306 end_log_pos 0 CRC32 0x0b8a412f Rotate to test-mysql-bin.000116 pos: 2451
  3. at 172 #170809 16:28:12 server id 1882073306 end_log_pos 0 CRC32 0xd0d3bf30 Start: binlog v 4, server v 5.6.23-72.1-log created 170809 16:28:12
  4. at 288 #170814 11:07:18 server id 1882073306 end_log_pos 2528 CRC32 0x40774a4b Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680038/!/; SET @@session.pseudo_thread_id=92/!/; SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/!/; SET @@session.sql_mode=1073741824/!/; SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/!/; /!\C utf8 //!/; SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=33/!/; SET @@session.lc_time_names=0/!/; SET @@session.collation_database=DEFAULT/!/; BEGIN /!/;
  5. at 365
  6. at 397 #170814 11:07:18 server id 1882073306 end_log_pos 2560 CRC32 0x7bdf274b Intvar SET INSERT_ID=107/!/; #170814 11:07:18 server id 1882073306 end_log_pos 2669 CRC32 0x68e441c8 Query thread_id=92 exec_time=0 error_code=0 use db1/!/; SET TIMESTAMP=1502680038/!/; insert into t2 (name) values ('a100') /!/;
  7. at 506
  8. at 538 #170814 11:07:27 server id 1882073306 end_log_pos 2701 CRC32 0xcf89b910 Intvar SET INSERT_ID=108/!/; #170814 11:07:27 server id 1882073306 end_log_pos 2810 CRC32 0x78466d7b Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680047/!/; insert into t2 (name) values ('a200') /!/;
  9. at 647
  10. at 679 #170814 11:07:30 server id 1882073306 end_log_pos 2842 CRC32 0x1e5a0847 Intvar SET INSERT_ID=109/!/; #170814 11:07:30 server id 1882073306 end_log_pos 2951 CRC32 0xebeb947c Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680050/!/; insert into t2 (name) values ('a300') /!/;
  11. at 788 #170814 11:07:34 server id 1882073306 end_log_pos 2982 CRC32 0x6436ad60 Xid = 32934 COMMIT/!/;

注意relay log的这一行：

#700101  8:00:00 server id 1882073306  end_log_pos 0 CRC32 0x0b8a412f  Rotate to test-mysql-bin.000116  pos: 2451

说明此relay log保存的是主库 test-mysql-bin.000116 的信息，从position 2451 开始。

看一个具体的对应关系：

主库的binlog如下：

  1. at 2560 #170814 11:07:18 server id 1882073306 end_log_pos 2560 CRC32 0x7bdf274b Intvar SET INSERT_ID=107/!/; #170814 11:07:18 server id 1882073306 end_log_pos 2669 CRC32 0x68e441c8 Query thread_id=92 exec_time=0 error_code=0 SET TIMESTAMP=1502680038/!/; insert into t2 (name) values ('a100') /!/;
  2. at 2669

对应从库relay-log如下几行：

  1. at 397 #170814 11:07:18 server id 1882073306 end_log_pos 2560 CRC32 0x7bdf274b Intvar SET INSERT_ID=107/!/; #170814 11:07:18 server id 1882073306 end_log_pos 2669 CRC32 0x68e441c8 Query thread_id=92 exec_time=0 error_code=0 use db1/!/; SET TIMESTAMP=1502680038/!/; insert into t2 (name) values ('a100') /!/;
  2. at 506

另外注意show slave status\G的以下几行的关系：

Master_Log_File: test-mysql-bin.000117 Read_Master_Log_Pos: 774

上面二行代表IO线程,相对于主库

Relay_Log_File: relay-log.000038 Relay_Log_Pos: 723

上面二行代表了sql线程,相对于从库

Relay_Master_Log_File: test-mysql-bin.000117 Exec_Master_Log_Pos: 555

上面二行代表了sql线程,相对主库

其中Relay_Log_Pos: 723 和 Exec_Master_Log_Pos: 555 对应的sql语句一致。

总结

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