数据库--释放mysql数据库资源

背景

nikeodong之前做了项目的数据库主从，在全备的过程发现数据库是越来越大了；最后发现是资源不释放的问题。

目的

为了解决mysql资源不释放的问题。

步骤

1、vim /etc/my.cnf，关闭log_bin日志。

2、导出数据库sql：time mysqldump -q -uroot -p'dpENoKNhG#y0w4sK' --max_allowed_packet=128M --net_buffer_length=16M -e --all-databases > XXXX.sql

3、删除mysql的data日志

    通过命令：show variables like 'datadir'，找到data目录
    或者通过vim /etc/my.cnf-->找到里面的datadir的值，找到data目录

4、重新导入表空间：mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/home/data/mysql --default-storage-engine=INNODB&

5、重新开启lob_bin日志

注意：在执行第二步的时候可能会报错

报错：Error: Table "mysql"."innodb_index_stats" not found。如下是解决方法

显示有几个系统表不存在.
innodb_table_stats
 innodb_index_stats
 或者
 slave_master_info
 slave_relay_log_info
 slave_worker_info

这是因为数据库初始化的时候,dba可能删除过ibdata1文件
虽然重启之后,数据库会自动创建一个ibdata1文件,因为是innodb引擎,所以不能访问了.

解决的方法如下：
删除上述系统表
drop table mysql.innodb_index_stats;
 drop table mysql.innodb_table_stats;
 drop table mysql.slave_master_info;
 drop table mysql.slave_relay_log_info;
 drop table mysql.slave_worker_info;

删除相关的.frm .ibd文件
rm -rf innodb_index_stats*
 rm -rf innodb_table_stats*
 rm -rf slave_master_info*
 rm -rf slave_relay_log_info*
 rm -rf slave_worker_info*

重新创建上述系统表
CREATE TABLE `innodb_index_stats` (
  `database_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `table_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `index_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `stat_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `stat_value` bigint(20) unsigned NOT NULL,
  `sample_size` bigint(20) unsigned DEFAULT NULL,
  `stat_description` varchar(1024) COLLATE utf8_bin NOT NULL,
  PRIMARY KEY (`database_name`,`table_name`,`index_name`,`stat_name`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin STATS_PERSISTENT=0;

 CREATE TABLE `innodb_table_stats` (
  `database_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `table_name` varchar(64) COLLATE utf8_bin NOT NULL,
  `last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `n_rows` bigint(20) unsigned NOT NULL,
  `clustered_index_size` bigint(20) unsigned NOT NULL,
  `sum_of_other_index_sizes` bigint(20) unsigned NOT NULL,
  PRIMARY KEY (`database_name`,`table_name`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin STATS_PERSISTENT=0;

 CREATE TABLE `slave_master_info` (
  `Number_of_lines` int(10) unsigned NOT NULL COMMENT 'Number of lines in the file.',
  `Master_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL COMMENT 'The name of the master binary log currently being read from the master.',
  `Master_log_pos` bigint(20) unsigned NOT NULL COMMENT 'The master log position of the last read event.',
  `Host` char(64) CHARACTER SET utf8 COLLATE utf8_bin NOT NULL DEFAULT '' COMMENT 'The host name of the master.',
  `User_name` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The user name used to connect to the master.',
  `User_password` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The password used to connect to the master.',
  `Port` int(10) unsigned NOT NULL COMMENT 'The network port used to connect to the master.',
  `Connect_retry` int(10) unsigned NOT NULL COMMENT 'The period (in seconds) that the slave will wait before trying to reconnect to the master.',
  `Enabled_ssl` tinyint(1) NOT NULL COMMENT 'Indicates whether the server supports SSL connections.',
  `Ssl_ca` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The file used for the Certificate Authority (CA) certificate.',
  `Ssl_capath` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The path to the Certificate Authority (CA) certificates.',
  `Ssl_cert` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The name of the SSL certificate file.',
  `Ssl_cipher` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The name of the cipher in use for the SSL connection.',
  `Ssl_key` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The name of the SSL key file.',
  `Ssl_verify_server_cert` tinyint(1) NOT NULL COMMENT 'Whether to verify the server certificate.',
  `Heartbeat` float NOT NULL,
  `Bind` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'Displays which interface is employed when connecting to the MySQL server',
  `Ignored_server_ids` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The number of server IDs to be ignored, followed by the actual server IDs',
  `Uuid` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The master server uuid.',
  `Retry_count` bigint(20) unsigned NOT NULL COMMENT 'Number of reconnect attempts, to the master, before giving up.',
  `Ssl_crl` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The file used for the Certificate Revocation List (CRL)',
  `Ssl_crlpath` text CHARACTER SET utf8 COLLATE utf8_bin COMMENT 'The path used for Certificate Revocation List (CRL) files',
  `Enabled_auto_position` tinyint(1) NOT NULL COMMENT 'Indicates whether GTIDs will be used to retrieve events from the master.',
  PRIMARY KEY (`Host`,`Port`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 STATS_PERSISTENT=0 COMMENT='Master Information';

 CREATE TABLE `slave_relay_log_info` (
  `Number_of_lines` int(10) unsigned NOT NULL COMMENT 'Number of lines in the file or rows in the table. Used to version table definitions.',
  `Relay_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL COMMENT 'The name of the current relay log file.',
  `Relay_log_pos` bigint(20) unsigned NOT NULL COMMENT 'The relay log position of the last executed event.',
  `Master_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL COMMENT 'The name of the master binary log file from which the events in the relay log file were read.',
  `Master_log_pos` bigint(20) unsigned NOT NULL COMMENT 'The master log position of the last executed event.',
  `Sql_delay` int(11) NOT NULL COMMENT 'The number of seconds that the slave must lag behind the master.',
  `Number_of_workers` int(10) unsigned NOT NULL,
  `Id` int(10) unsigned NOT NULL COMMENT 'Internal Id that uniquely identifies this record.',
  PRIMARY KEY (`Id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 STATS_PERSISTENT=0 COMMENT='Relay Log Information';

 CREATE TABLE `slave_worker_info` (
  `Id` int(10) unsigned NOT NULL,
  `Relay_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `Relay_log_pos` bigint(20) unsigned NOT NULL,
  `Master_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `Master_log_pos` bigint(20) unsigned NOT NULL,
  `Checkpoint_relay_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `Checkpoint_relay_log_pos` bigint(20) unsigned NOT NULL,
  `Checkpoint_master_log_name` text CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `Checkpoint_master_log_pos` bigint(20) unsigned NOT NULL,
  `Checkpoint_seqno` int(10) unsigned NOT NULL,
  `Checkpoint_group_size` int(10) unsigned NOT NULL,
  `Checkpoint_group_bitmap` blob NOT NULL,
  PRIMARY KEY (`Id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 STATS_PERSISTENT=0 COMMENT='Worker Information';

在执行删除表的时候报错也没关系，一直从头走到尾就好。

完成之后查看一下大小

du -sh /var/lib/mysql 看看数据库是否瘦身成功