【Mysql】Mysql 从库每隔一段时间就重启 - MySQL数据库

背景：HuaYun_Interface-SLAVE从库每隔一段时间slave复制进程便停掉，zabbix发送告警短信

1. mysql> show slave statusG;
   
2. *************************** 1. row ***************************
3.                Slave_IO_State:
4.                   Master_Host: *****
5.                   Master_User: repl
6.                   Master_Port: 3307
7.                 Connect_Retry: 60
8.               Master_Log_File: mysql–bin.000195
9.           Read_Master_Log_Pos: 629275501
10.                Relay_Log_File: mysql–relay–bin.000521
11.                 Relay_Log_Pos: 625430128
12.         Relay_Master_Log_File: mysql–bin.000195
13.              Slave_IO_Running: No
14.             Slave_SQL_Running: No

停掉时查看mysql错误日志我们发现端倪

1. 2016-06-23 14:06:56 32289 [Warning] ’proxies_priv’ entry ’@ root@sh275’ ignored in –skip-name-resolve mode.
   160623 15:03:49 mysqld_safe Number of processes running now: 0
   160623 15:03:49 mysqld_safe mysqld restarted                 —–发现是mysql服务重启了，而我们配置了skip_slave_start（禁止repl进程自动重启），所以复制进程处于down状态
   2016-06-23 15:03:50 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use –explicit_defaults_for_timestamp server option (see documentation for more details).
   2016-06-23 15:03:50 0 [Note] /home/data/mysql/bin/mysqld (mysqld 5.6.24-log) starting as process 22569 …
   2016-06-23 15:03:50 22569 [Note] Plugin ’FEDERATED’ is disabled.
   2016-06-23 15:03:50 22569 [Note] InnoDB: Using atomics to ref count buffer pool pages
   2016-06-23 15:03:50 22569 [Note] InnoDB: The InnoDB memory heap is disabled
   2016-06-23 15:03:50 22569 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
   2016-06-23 15:03:50 22569 [Note] InnoDB: Memory barrier is not used
   2016-06-23 15:03:50 22569 [Note] InnoDB: Compressed tables use zlib 1.2.3
   2016-06-23 15:03:50 22569 [Note] InnoDB: Using Linux native AIO
   2016-06-23 15:03:50 22569 [Note] InnoDB: Not using CPU crc32 instructions
   2016-06-23 15:03:50 22569 [Note] InnoDB: Initializing buffer pool, size = 10.0G
   2016-06-23 15:03:51 22569 [Note] InnoDB: Completed initialization of buffer pool

同时我们查看zabbix发送的邮件，有linux主机内存报警通知

1. 告警主机：_HuaYun_Interface–SLAVE
   
2. 主机IP： ******
3. 告警时间：2016.06.23 15:08:06
4. 告警等级：Average
5. 告警信息：Lack of available memory on server HuaYun_Interface–SLAVE
6. 问题详情：Available memory:163.15 MB
7. 事件ID： 42590

登上主机检查

1. [root@NEW-APP-MYSQL-SLAVE ~]# dmesg 
   
2. Out of memory: Kill process 32289 (mysqld) score 966 or sacrifice child
   
3. Killed process 32289, UID 498, (mysqld) total–vm:14630648kB, anon–rss:7711284kB, file–rss:360kB

[root@NEW-APP-MYSQL-SLAVE ~]# free -m
             total       used       free     shared    buffers     cached
Mem:          7872       7747        124          0        124       1331
-/+ buffers/cache:       6292       1580
Swap:         2047         56       1991

很明显是linux内存不足而发生了OOM killer现象，没办法，加大主机内存吧