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本篇内容介绍了“怎么理解从库的IO线程”的有关知识，在实际案例的操作过程中，不少人都会遇到这样的困境，接下来就让小编带领大家学习一下如何处理这些情况吧！希望大家仔细阅读，能够学有所成！
一、流程解析
start_slave
->start_slave_threads
->
if (!mi->inited || !mi->rli->inited)//如果没有初始化
{
int error= (!mi->inited ? ER_SLAVE_MI_INIT_REPOSITORY :
ER_SLAVE_RLI_INIT_REPOSITORY);
ER_SLAVE_MI_INIT_REPOSITORY
ER_SLAVE_RLI_INIT_REPOSITORY
->
if (mi->is_auto_position() && (thread_mask & SLAVE_IO) &&
get_gtid_mode(GTID_MODE_LOCK_NONE) == GTID_MODE_OFF)
ER_CANT_USE_AUTO_POSITION_WITH_GTID_MODE_OFF eng
"The replication receiver thread%-.192s cannot start in
AUTO_POSITION mode: this server uses @@GLOBAL.GTID_MODE = OFF."
-> 启动IO 线程
if (thread_mask & SLAVE_IO)
is_error= start_slave_thread(
#ifdef HAVE_PSI_INTERFACE
key_thread_slave_io,
#endif
handle_slave_io, lock_io, lock_cond_io,
cond_io,
&mi->slave_running, &mi->slave_run_id,
mi);
-> mysql_thread_create 建立线程 回调函数handle_slave_io
->handle_slave_io
->初始化IO线程属性 init_slave_thread
进入状态THD_STAGE_INFO(thd, stage_waiting_for_master_update);
->safe_connect 进行连接主库
->connect_to_master
->将参数slave_net_timeout设置为IO线程连接超时和IO线程读取Event 超时
case MYSQL_OPT_CONNECT_TIMEOUT: //MYSQL_OPT_CONNECT_TIMEOUT
mysql->options.connect_timeout= *(uint*) arg;
break;
case MYSQL_OPT_READ_TIMEOUT://MYSQL_OPT_READ_TIMEOUT
mysql->options.read_timeout= *(uint*) arg;
break;
->循环 实现连接和重新连接
-> 根据用户名、密码、IP、端口建立连接
mysql_real_connect(mysql, mi->host, user, password, 0, mi->port, 0, client_flag)
->如果连接失败 循环重连
每次打印日志
mi->report(ERROR_LEVEL, last_errno,
"error %s to master '%s@%s:%d'"
" - retry-time: %d retries: %lu",
(reconnect ? "reconnecting" : "connecting"),
mi->get_user(), mi->host, mi->port,
mi->connect_retry, err_count + 1);
if (++err_count == mi->retry_count)
{
slave_was_killed=1;
break;
}
slave_sleep(thd, mi->connect_retry, io_slave_killed, mi); //睡眠时间
每次睡眠时间为MASTER_CONNECT_RETRY设置的时间，默认60秒，循环次数由MASTER_RETRY_COUNT指定
默认86400次
->get_master_version_and_clock
->比较版本
->发起命令SELECT UNIX_TIMESTAMP() 获取主库时间
mysql_real_query(mysql, STRING_WITH_LEN("SELECT UNIX_TIMESTAMP()
计算差值用于延迟计算
mi->clock_diff_with_master= (long) (time((time_t*) 0) - strtoul(master_row[0], 0, 10));
也就是说差值计算是在start slave命令发起的时候进行计算的，后面如果修改slave的服务器时间
那么延迟计算将出现问题
->发起命令SELECT @@GLOBAL.SERVER_ID 获取主库server id
比较主库的server id和本从库是否相同，如果相同则报错
The slave I/O thread stops because master and slave have equal \
MySQL server ids; these ids must be different for replication to work (or \
the --replicate-same-server-id option must be used on slave but this does \
not always make sense; please check the manual before using it).
->发起命令SELECT @@GLOBAL.COLLATION_SERVER
如果主库的这个值和备库不一致将会报错
The slave I/O thread stops because master and slave have \
different values for the COLLATION_SERVER global variable. The values must \
be equal for the Statement-format replication to work
->发起命令SELECT @@GLOBAL.TIME_ZONE 老版本检测
比较主库和从库的时区，如果不一致
The slave I/O thread stops because master and slave have \
different values for the TIME_ZONE global variable. The values must \
be equal for the Statement-format replication to work
->发起命令SELECT @@GLOBAL.GTID_MODE
比较主库和从库的GTID MODE是否兼容
if ((slave_gtid_mode == GTID_MODE_OFF &&
master_gtid_mode >= GTID_MODE_ON_PERMISSIVE) ||
(slave_gtid_mode == GTID_MODE_ON &&
master_gtid_mode <= GTID_MODE_OFF_PERMISSIVE))
{
mi->report(ERROR_LEVEL, ER_SLAVE_FATAL_ERROR,
"The replication receiver thread cannot start because "
"the master has GTID_MODE = %.192s and this server has "
"GTID_MODE = %.192s.",
get_gtid_mode_string(master_gtid_mode),
get_gtid_mode_string(slave_gtid_mode));
DBUG_RETURN(1);
}
if (mi->is_auto_position() && master_gtid_mode != GTID_MODE_ON)
{
mi->report(ERROR_LEVEL, ER_SLAVE_FATAL_ERROR,
"The replication receiver thread cannot start in "
"AUTO_POSITION mode: the master has GTID_MODE = %.192s "
"instead of ON.",
get_gtid_mode_string(master_gtid_mode));
DBUG_RETURN(1);
}
->回到handle_slave_io
->get_master_uuid 获取主句UUID 比较UUID
发起命令SELECT @@GLOBAL.SERVER_UUID
比较主库和备库的UUID如果相同报错
"The slave I/O thread stops because master and slave have equal "
"MySQL server UUIDs; these UUIDs must be different for "
"replication to work."
->io_thread_init_commands
SET @slave_uuid= '%s' 是什么意思
->register_slave_on_master 进行注册
主库调用register_slave进行注册
注册完成后 show slave hosts就能查询到了 主库show slave会调用
show_slave_hosts 函数
->request_dump 发送需要读取的GTID或者位点信息给主库。
如果是AUTO com_binlog_dump_gtid
- restirve_gtid+execute_gtid
if (gtid_executed.add_gtid_set(mi->rli->get_gtid_set()) != RETURN_STATUS_OK ||
gtid_executed.add_gtid_set(gtid_state->get_executed_gtids()) !=
RETURN_STATUS_OK)
- server_id
主库读取
(gdb) p gtid_string
$17 = 0x7ffee400ef20 "010fde77-2075-11e9-ba07-5254009862c0:1,\ncb7ea36e-670f-11e9-b483-5254008138e4:1-16"
(gdb) p name
$18 = '\000' <repeats 16 times>, "\v\000\000\000\a\000\000\000\000\t\000\344\376\177\000\000\340\252U\354\377\177\000\000\242kL\001\000\000\000\000\002\000\000\000\000\000\000\000\346?\001\000\000\000\000\002\000\000\000\000\000\000\000\346?\001\000\000\000\000\300\252U\354\377\177\000\000L?\001\n\000\000\000ЪU\354\377\177\000\000L?\001\000\000\000\000\360\252U\354\377\177\000\000\240\343\221\001\000\000\000\000\000\253U\354\377\177\000\000\340\b\000\344\376\177\000\000\020\253U\354\377\177\000\000\"I\353\001\000\000\000\000\000\t\000\344\376\177\000\000\240\255U\354\377\177\000\000\060\253U\354\377\177\000\000\272~\356\000\000\000\000\000\v\000\000\000\005\000\000\000\240\255U\354\377\177\000\000\000\256U\354\377\177\000\000\246\323M\001\000\000\000\000\221\333/\002\000\000\000\000\030=\000\344\376\177", '\000' <repeats 18 times>, "\002\000\000\000\000\000\000\000\346?\001\000\000\000\000\016\202\036\002\000\000\000\000\250"...
(gdb) p pos
$19 = 4
不是AUTO
- server_id
- MASTER INFO 表的读取位点
- MASTER INFO 表的读取binlog文件名
主库读取 com_binlog_dump
(gdb) p pos
$1 = 3587
(gdb) p packet + 10
$3 = 0x7ffedc00a88b "binlog.000005"
我们可以看到即便开启了GTID不开启AUTO也不会根据GTID来读取。
->循环读取event
进入状态 stage_waiting_for_master_to_send_event
->将读取的event写入到 relay log
进入状态Queueing master event to the relay log
->queue_event 读取的event写入到 relay log
检测GTID event的合法性
Cannot replicate GTID-transaction when @@GLOBAL.GTID_MODE = OFF, at file %.512s, position %lld.
Cannot replicate anonymous transaction when AUTO_POSITION = 1, at file %.512s, position %lld.
Cannot replicate anonymous transaction when @@GLOBAL.GTID_MODE = ON, at file %.512s, position %lld.
->rli->relay_log.append_buffer 进行relay log写入
->MYSQL_BIN_LOG::after_append_to_relay_log //进行写入后处理
->flush_and_sync 函数根据relay log sync参数设置决定是否做sync操作 单位是event个数
->MYSQL_BIN_LOG::sync_binlog_file 判断是否进行刷盘
->can_rotate 根据这个值决定是否计入Retrieved_Gtid_Set 边界分析器
->进行relay log切换
->更改相关被变量
master 位置/master 文件
增加容量log_space_total
mi->set_master_log_pos(mi->get_master_log_pos() + inc_pos);//增加master 位置
rli->relay_log.harvest_bytes_written(&rli->log_space_total);
/*
If this event is GTID_LOG_EVENT we store its GTID to add to the
Retrieved_Gtid_Set later, when the last event of the transaction be
queued.
*/
if (event_type == binary_log::GTID_LOG_EVENT)
{
mi->set_last_gtid_queued(gtid);
}
->flush_master_info(mi, FALSE)
->Rpl_info_table::do_flush_info
通过参数sync_master设置决定多少个event 进行写table
handler->set_sync_period(sync_masterinfo_period);
if (!(force || (sync_period &&
++(sync_counter) >= sync_period)))//如果没有达到 sync的次数(sync_master_info 或者 sync_relay_log_info次数 不做flush 不写表 直接返回)
DBUG_RETURN(0);//但是relay_log_info依赖于是否是table模式如果是table模式则会在commit的时候做相应的flush Slave_worker::flush_info设置sync_master_info=1
主库做一个大事务，观察slave_master_info表如下：
mysql> select * from slave_master_info \G; *************************** 1. row *************************** Number_of_lines: 25 Master_log_name: binlog.000002 Master_log_pos: 1222540
主库执行：
/mysqldata/mysql3340/bin/mysqlbinlog binlog.000002 --base64-output='decode-rows'|grep -C 10 -E "BEGIN|COMMIT"
主库event 可以看到在中间
BEGIN /*!*/; # at 992468 #190519 13:07:26 server id 413340 end_log_pos 992520 CRC32 0x5d85ea03 Table_map: `testmts`.`testio` mapped to number 111 # at 992520 #190519 13:07:26 server id 413340 end_log_pos 1000735 CRC32 0xfceb6697 Write_rows: table id 111 # at 1000735 #190519 13:07:26 server id 413340 end_log_pos 1008950 CRC32 0x0ca6515c Write_rows: table id 111 # at 1008950 #190519 13:07:26 server id 413340 end_log_pos 1017165 CRC32 0x21d7b17d Write_rows: table id 111 # at 1017165 -- # at 2939475 #190519 13:07:26 server id 413340 end_log_pos 2947690 CRC32 0xcb553fab Write_rows: table id 111 # at 2947690 #190519 13:07:26 server id 413340 end_log_pos 2955905 CRC32 0xd42382c9 Write_rows: table id 111 # at 2955905 #190519 13:07:26 server id 413340 end_log_pos 2964120 CRC32 0xe516b98a Write_rows: table id 111 # at 2964120 #190519 13:07:26 server id 413340 end_log_pos 2967035 CRC32 0x9cbfbc0a Write_rows: table id 111 flags: STMT_END_F # at 2967035 #190519 13:07:26 server id 413340 end_log_pos 2967066 CRC32 0xb907da17 Xid = 45 COMMIT/*!*/; SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/; DELIMITER ; # End of log file /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/; You have mail in /var/spool/mail/root
下面是 recover_relay_log=0 的情况 POS和GTID AUTO_POSITION=1不同的处理。
断点
Master_info::set_master_log_pos 设置master info io thread 读取主库的binlog pos Relay_log_info::set_group_relay_log_pos 设置relay info sql thread 从库读取relay pos的位置
GTID
AUTO_POSITION binlog recover_relay_log=0的情况下：
DUMP线程会重新发送最后一个事务给从库，从库使用Crash前的Relay_Log_Pos进行读取。relay log可能出现不完整的事务。这种情况会触发回滚机制。单线程会在GTID event 中回滚，MTS会由协调线程调用coord_handle_partial_binlogged_transaction回滚
change master to master_host='192.168.99.41', master_user='repl', master_password='gelc123', master_port=3340, AUTO_POSITION=1; start slave;
主库：
# at 912 #190519 21:22:16 server id 413340 end_log_pos 977 CRC32 0x5840ca71 GTID last_committed=1 sequence_number=2 rbr_only=yes /*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/; SET @@SESSION.GTID_NEXT= 'cb7ea36e-670f-11e9-b483-5254008138e4:2'/*!*/; # at 977 #190519 21:22:16 server id 413340 end_log_pos 1052 CRC32 0xcd8345de Query thread_id=3 exec_time=13 error_code=0 SET TIMESTAMP=1558272136/*!*/; BEGIN /*!*/; # at 1052 #190519 21:22:16 server id 413340 end_log_pos 1104 CRC32 0x782391dd Table_map: `testmts`.`testgp` mapped to number 108 # at 1104 #190519 21:22:16 server id 413340 end_log_pos 9319 CRC32 0x8de0fbdd Write_rows: table id 108 # at 9319 #190519 21:22:16 server id 413340 end_log_pos 17534 CRC32 0xae798162 Write_rows: table id 108 # at 17534 #190519 21:22:16 server id 413340 end_log_pos 25749 CRC32 0x683b9e95 Write_rows: table id 108 # at 25749 -- # at 477574 #190519 21:22:16 server id 413340 end_log_pos 485789 CRC32 0x44e99850 Write_rows: table id 108 # at 485789 #190519 21:22:16 server id 413340 end_log_pos 494004 CRC32 0x280300fd Write_rows: table id 108 # at 494004 #190519 21:22:16 server id 413340 end_log_pos 502219 CRC32 0x075c8ff8 Write_rows: table id 108 # at 502219 #190519 21:22:16 server id 413340 end_log_pos 503274 CRC32 0x08c3f96c Write_rows: table id 108 flags: STMT_END_F # at 503274 #190519 21:22:16 server id 413340 end_log_pos 503305 CRC32 0x3b6dd31c Xid = 26 COMMIT/*!*/; SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/; DELIMITER ;
mysql> show slave status \G *************************** 1. row *************************** Slave_IO_State: Queueing master event to the relay log Master_Host: 192.168.99.41 Master_User: repl Master_Port: 3340 Connect_Retry: 60 Master_Log_File: binlog.000001 Read_Master_Log_Pos: 165404 Relay_Log_File: relay.000002 Relay_Log_Pos: 1119 Relay_Master_Log_File: binlog.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes
crash 后
mysql> show slave status \G *************************** 1. row *************************** Slave_IO_State: Master_Host: 192.168.99.41 Master_User: repl Master_Port: 3340 Connect_Retry: 60 Master_Log_File: binlog.000001 Read_Master_Log_Pos: 190049 Relay_Log_File: relay.000002 Relay_Log_Pos: 1119 Relay_Master_Log_File: binlog.000001
不完整的事物日志如下：
# at 1119 #190519 21:22:16 server id 413340 end_log_pos 977 CRC32 0x5840ca71 GTID last_committed=1 sequence_number=2 rbr_only=yes /*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/; SET @@SESSION.GTID_NEXT= 'cb7ea36e-670f-11e9-b483-5254008138e4:2'/*!*/; # at 1184 #190519 21:22:16 server id 413340 end_log_pos 1052 CRC32 0xcd8345de Query thread_id=3 exec_time=13 error_code=0 SET TIMESTAMP=1558272136/*!*/; BEGIN /*!*/; # at 1259 #190519 21:22:16 server id 413340 end_log_pos 1104 CRC32 0x782391dd Table_map: `testmts`.`testgp` mapped to number 108 # at 1311 #190519 21:22:16 server id 413340 end_log_pos 9319 CRC32 0x8de0fbdd Write_rows: table id 108 # at 9526 #190519 21:22:16 server id 413340 end_log_pos 17534 CRC32 0xae798162 Write_rows: table id 108 # at 17741 #190519 21:22:16 server id 413340 end_log_pos 25749 CRC32 0x683b9e95 Write_rows: table id 108 # at 25956 WARNING: The range of printed events ends with a row event or a table map event that does not have the STMT_END_F flag set. This might be because the last statement was not fully written to the log, or because you are using a --stop-position or --stop-datetime that refers to an event in the middle of a statement. The event(s) from the partial statement have not been written to output.
启动后 IO_THREAD
mysql> show slave status \G *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.99.41 Master_User: repl Master_Port: 3340 Connect_Retry: 60 Master_Log_File: binlog.000001 Read_Master_Log_Pos: 503305 Relay_Log_File: relay.000002 Relay_Log_Pos: 1119 Relay_Master_Log_File: binlog.000001 Slave_IO_Running: Yes Slave_SQL_Running: No
启动IO TRHEAD后 重新传输了，但是老的没有完全传输完成的日志还在relay log
新的日志已经有了 ，老的也还在。
# at 445 #190519 21:22:16 server id 413340 end_log_pos 977 CRC32 0x5840ca71 GTID last_committed=1 sequence_number=2 rbr_only=yes /*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/; SET @@SESSION.GTID_NEXT= 'cb7ea36e-670f-11e9-b483-5254008138e4:2'/*!*/; # at 510 #190519 21:22:16 server id 413340 end_log_pos 1052 CRC32 0xcd8345de Query thread_id=3 exec_time=13 error_code=0 SET TIMESTAMP=1558272136/*!*/; SET @@session.pseudo_thread_id=3/*!*/; SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/; SET @@session.sql_mode=1075838976/*!*/; SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/; /*!\C utf8 *//*!*/; SET @@session.character_set_client=83,@@session.collation_connection=83,@@session.collation_server=33/*!*/; SET @@session.lc_time_names=0/*!*/; SET @@session.collation_database=DEFAULT/*!*/; BEGIN /*!*/; # at 585 #190519 21:22:16 server id 413340 end_log_pos 1104 CRC32 0x782391dd Table_map: `testmts`.`testgp` mapped to number 108 # at 637 #190519 21:22:16 server id 413340 end_log_pos 9319 CRC32 0x8de0fbdd Write_rows: table id 108 # at 8852 #190519 21:22:16 server id 413340 end_log_pos 17534 CRC32 0xae798162 Write_rows: table id 108 # at 17067 #190519 21:22:16 server id 413340 end_log_pos 25749 CRC32 0x683b9e95 Write_rows: table id 108 (以上本来已经传输了) # at 25282 -- # at 477107 #190519 21:22:16 server id 413340 end_log_pos 485789 CRC32 0x44e99850 Write_rows: table id 108 # at 485322 #190519 21:22:16 server id 413340 end_log_pos 494004 CRC32 0x280300fd Write_rows: table id 108 # at 493537 #190519 21:22:16 server id 413340 end_log_pos 502219 CRC32 0x075c8ff8 Write_rows: table id 108 # at 501752 #190519 21:22:16 server id 413340 end_log_pos 503274 CRC32 0x08c3f96c Write_rows: table id 108 flags: STMT_END_F # at 502807 #190519 21:22:16 server id 413340 end_log_pos 503305 CRC32 0x3b6dd31c Xid = 26 COMMIT/*!*/;
POSITION
在 recover_relay_log=0的情况下从库会从Read_Master_Log_Pos的位置接着拉取replay log，一旦Read_Master_Log_Pos和replay log出现问题那么将会导致从库异常。主库只需要从Relay_Log_Pos的位置应用即可。因此参数
sync_relay_log=1
sync_master_info=1
是必须的。
change master to master_host='192.168.99.41', master_user='repl', master_password='gelc123', master_port=3340, MASTER_LOG_FILE='binlog.000001', MASTER_LOG_POS=154; start slave;
mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.99.41 Master_User: repl Master_Port: 3340 Connect_Retry: 60 Master_Log_File: binlog.000001 Read_Master_Log_Pos: 912 Relay_Log_File: relay.000002 Relay_Log_Pos: 1075 Relay_Master_Log_File: binlog.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes
写入途中：
mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Queueing master event to the relay log Master_Host: 192.168.99.41 Master_User: repl Master_Port: 3340 Connect_Retry: 60 Master_Log_File: binlog.000001 Read_Master_Log_Pos: 124329 Relay_Log_File: relay.000002 Relay_Log_Pos: 1075 Relay_Master_Log_File: binlog.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes
主库binlog：
BEGIN /*!*/; # at 1052 #190519 16:43:43 server id 413340 end_log_pos 1104 CRC32 0x1b959719 Table_map: `testmts`.`testgp` mapped to number 108 # at 1104 #190519 16:43:43 server id 413340 end_log_pos 9319 CRC32 0x98ff5e73 Write_rows: table id 108 # at 9319 #190519 16:43:43 server id 413340 end_log_pos 17534 CRC32 0xbb6624cc Write_rows: table id 108 # at 17534 #190519 16:43:43 server id 413340 end_log_pos 25749 CRC32 0x7d243b3b Write_rows: table id 108 # at 25749 -- # at 477574 #190519 16:43:43 server id 413340 end_log_pos 485789 CRC32 0x51f63dfe Write_rows: table id 108 # at 485789 #190519 16:43:43 server id 413340 end_log_pos 494004 CRC32 0x3d1ca553 Write_rows: table id 108 # at 494004 #190519 16:43:43 server id 413340 end_log_pos 502219 CRC32 0x12432a56 Write_rows: table id 108 # at 502219 #190519 16:43:43 server id 413340 end_log_pos 503274 CRC32 0x4373f461 Write_rows: table id 108 flags: STMT_END_F # at 503274 #190519 16:43:43 server id 413340 end_log_pos 503305 CRC32 0xe33a6266 Xid = 60 COMMIT/*!*/;
Crash启动后日志如下：
# at 321652 #190519 16:43:43 server id 413340 end_log_pos 329704 CRC32 0xbf87ced1 Write_rows: table id 108 # at 329867 #190519 16:43:43 server id 413340 end_log_pos 337919 CRC32 0x2f3bd840 Write_rows: table id 108 # at 338082 #190519 16:43:43 server id 413340 end_log_pos 346134 CRC32 0xe317c093 Write_rows: table id 108 # at 346297 #190519 16:43:43 server id 413340 end_log_pos 354349 CRC32 0x81e3ea0d Write_rows: table id 108 # at 354512 #190519 16:43:43 server id 413340 end_log_pos 362564 CRC32 0x7f51fc3a Write_rows: table id 108 # at 362727 #190519 16:25:17 server id 953340 end_log_pos 362770 CRC32 0xb6611a85 Rotate to relay.000003 pos: 4 WARNING: The range of printed events ends with a row event or a table map event that does not have the STMT_END_F flag set. This might be because the last statement was not fully written to the log, or because you are using a --stop-position or --stop-datetime that refers to an event in the middle of a statement. The event(s) from the partial statement have not been written to output. ROLLBACK /* added by mysqlbinlog */ /*!*/; SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/; DELIMITER ; # End of log file /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/; [root@gp1 log]# /mysqldata/mysql3340/bin/mysqlbinlog --base64-output='decode-rows' relay.000003 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; DELIMITER /*!*/; # at 4 #190519 16:25:17 server id 953340 end_log_pos 123 CRC32 0xe6fd01bf Start: binlog v 4, server v 5.7.22-22-debug-log created 190519 16:25:17 # This Format_description_event appears in a relay log and was generated by the slave thread. # at 123 #190519 16:25:17 server id 953340 end_log_pos 154 CRC32 0xde5482b5 Previous-GTIDs # [empty] # at 154 #700101 8:00:00 server id 413340 end_log_pos 0 CRC32 0x86e86060 Rotate to binlog.000001 pos: 362564 # at 198 #190519 16:42:31 server id 413340 end_log_pos 0 CRC32 0x5361aca0 Start: binlog v 4, server v 5.7.22-22-debug-log created 190519 16:42:31 # at 317 #190519 16:43:43 server id 413340 end_log_pos 370779 CRC32 0x8b7abae8 Write_rows: table id 108 # at 8532 #190519 16:43:43 server id 413340 end_log_pos 378994 CRC32 0x28e1279c Write_rows: table id 108 # at 16747 #190519 16:43:43 server id 413340 end_log_pos 387209 CRC32 0x278d98ed Write_rows: table id 108 # at 24962 #190519 16:43:43 server id 413340 end_log_pos 395424 CRC32 0x85d21655 Write_rows: table id 108 # at 33177 #190519 16:43:43 server id 413340 end_log_pos 403639 CRC32 0x156e00c4 Write_rows: table id 108 # at 41392 #190519 16:43:43 server id 413340 end_log_pos 411854 CRC32 0xed83b3ac Write_rows: table id 108 # at 49607 #190519 16:43:43 server id 413340 end_log_pos 420069 CRC32 0x465939b4 Write_rows: table id 108 # at 57822 #190519 16:43:43 server id 413340 end_log_pos 428284 CRC32 0xaab146d2 Write_rows: table id 108 # at 66037 #190519 16:43:43 server id 413340 end_log_pos 436499 CRC32 0x97f1428f Write_rows: table id 108 WARNING: The range of printed events ends with a row event or a table map event that does not have the STMT_END_F flag set. This might be because the last statement was not fully written to the log, or because you are using a --stop-position or --stop-datetime that refers to an event in the middle of a statement. The event(s) from the partial statement have not been written to output. SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/; DELIMITER ; # End of log file /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/; [root@gp1 log]# /mysqldata/mysql3340/bin/mysqlbinlog --base64-output='decode-rows' relay.000005 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; DELIMITER /*!*/; # at 4 #190519 16:31:57 server id 953340 end_log_pos 123 CRC32 0xecc598ac Start: binlog v 4, server v 5.7.22-22-debug-log created 190519 16:31:57 # This Format_description_event appears in a relay log and was generated by the slave thread. # at 123 #190519 16:31:57 server id 953340 end_log_pos 154 CRC32 0x21c8a43a Previous-GTIDs # [empty] # at 154 #700101 8:00:00 server id 413340 end_log_pos 0 CRC32 0xeed34528 Rotate to binlog.000001 pos: 428284 # at 198 #190519 16:42:31 server id 413340 end_log_pos 0 CRC32 0x5361aca0 Start: binlog v 4, server v 5.7.22-22-debug-log created 190519 16:42:31 # at 317 #190519 16:43:43 server id 413340 end_log_pos 436499 CRC32 0x97f1428f Write_rows: table id 108 # at 8532 #190519 16:43:43 server id 413340 end_log_pos 444714 CRC32 0xfd447f7d Write_rows: table id 108 # at 16747 #190519 16:43:43 server id 413340 end_log_pos 452929 CRC32 0xc4c67bff Write_rows: table id 108 # at 24962 #190519 16:43:43 server id 413340 end_log_pos 461144 CRC32 0x6dbd096a Write_rows: table id 108 # at 33177 #190519 16:43:43 server id 413340 end_log_pos 469359 CRC32 0xb42d58b6 Write_rows: table id 108 # at 41392 #190519 16:43:43 server id 413340 end_log_pos 477574 CRC32 0x7a2e502d Write_rows: table id 108 # at 49607 #190519 16:43:43 server id 413340 end_log_pos 485789 CRC32 0x51f63dfe Write_rows: table id 108 # at 57822 #190519 16:43:43 server id 413340 end_log_pos 494004 CRC32 0x3d1ca553 Write_rows: table id 108 # at 66037 #190519 16:43:43 server id 413340 end_log_pos 502219 CRC32 0x12432a56 Write_rows: table id 108 # at 74252 #190519 16:43:43 server id 413340 end_log_pos 503274 CRC32 0x4373f461 Write_rows: table id 108 flags: STMT_END_F # at 75307 #190519 16:43:43 server id 413340 end_log_pos 503305 CRC32 0xe33a6266 Xid = 60 COMMIT/*!*/; SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/;
从 end_log_pos 可以看到他们凑成了一个完整的事务日志。
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