Mysql Percona 备份正在关闭 mysql 实例

Question

我正在运行我的 mysql 数据库的基本备份。我不确定它为什么要关闭。我收到备份完成消息，准备完成后我正在完成。但是实例仍然崩溃。我正在运行两个实例，我只在备份一个。

xtrabackup --defaults-file=/etc/alternatives/my.cnf --defaults-group=mysqld5 --socket=/var/run/mysqld/db5.sock --user=mysqladmin --password=password --backup --throttle 400 --target-dir=/mysqlbackup/current --no-timestamp 2> /var/backup.log;

我收集日志文件以确保它已完成并且确实完成了。然后我运行准备

xtrabackup --prepare --use-memory=5G --target-dir=/mysqlbackup/current 2 >> /var/backup.log;

我的日志文件有

xtrabackup: cd to /mysqlbackup/current
xtrabackup: This target seems to be not prepared yet.                                                                                                                                                                                                                                                                                                                           

Doing recovery: scanned up to log sequence number 5642017177088 (8%)
Doing recovery: scanned up to log sequence number 5642076559654 (99%)
Database was not shutdown normally
Starting crash recovery
Progress in percent: 0 1 2 ... 99
Apply batch completed
InnoDB: 96 redo rollback segment(s) found. 1 redo rollback segment(s) are active.                                                                                                                                                                                                                                                                                                
InnoDB: 32 non-redo rollback segment(s) are active.                                                                                                                                                                                                                                                                                                                              
InnoDB: page_cleaner: 1000ms intended loop took 748935ms. The settings might not be optimal. (flushed=0 and evicted=0, during the time.)                                                                                                                                                                                                                                         
InnoDB: 5.7.26 started; log sequence number 5642076559654 
xtrabackup: Last MySQL binlog file position 7017599, file name binlog.000009
xtrabackup: Recovered WSREP position: febfad99-09fe-11ea-ad83-57c73422d738:27384750                                                                                                                                                                                                                                                                                              
xtrabackup: starting shutdown with innodb_fast_shutdown = 1                                                                                                                                                                                                                                                                                                                      
InnoDB: FTS optimize thread exiting.                                                                                                                                                                                                                                                                                                                                             
InnoDB: Starting shutdown...                                                                                                                                                                                                                                                                                                                                                     
InnoDB: Shutdown completed; log sequence number 5642076561674                                                                                                                                                                                                                                                                                                                    
InnoDB: Number of pools: 1                                      
xtrabackup:   innodb_data_home_dir = . 
InnoDB: New log files created, LSN=5642076561674
InnoDB: Doing recovery: scanned up to log sequence number 5642076561941 (0%) 
InnoDB: Database was not shutdown normally! 
InnoDB: Starting crash recovery
InnoDB: Starting shutdown...                                                                                                                                                                                                                                                                                                                                                     
InnoDB: Shutdown completed; log sequence number 5642076561960                                                                                                                                                                                                                                                                                                                    
200213 08:05:36 completed OK!  

Answer 1

连接到您正在运行的 MySQL 服务器，并在客户端中运行它：

mysql> SHOW STATUS LIKE 'Uptime';
+---------------+--------+
| Variable_name | Value  |
+---------------+--------+
| Uptime        | 268121 |
+---------------+--------+

该值是自您的 MySQL 服务器上次启动以来的秒数（我上面显示的示例来自我自己笔记本电脑上的 mysql，计算结果为 74 小时，这是我上次重新启动的时间）。

我认为您会发现 uptime 值表明您的 MySQL 服务器在备份期间一直运行良好。

Percona XtraBackup 不会重新启动您的 MySQL 服务器。它重新启动自己的 InnoDB 引擎，以针对刚刚备份的文件模拟崩溃恢复。

XtraBackup 使用了大量从 MySQL 本身的 InnoDB 引擎借用的代码，因此它保持与 InnoDB 文件格式的兼容性。它使用 InnoDB 的崩溃恢复功能来“准备”其 InnoDB 文件的副本，以解决任何未完成的事务。

通过借用 InnoDB 引擎的代码，输出类似的消息。