需求描述:
在mysql中如何删除binlog,因为随着数据库的运行,mysql中产生的binlog会越来越大,有可能把磁盘撑爆了,所以记录下删除
binlog的方法.
操作过程:
1.通过系统参数控制保留多久的binlog
在my.cnf中,加入以下的参数,重启实例
expire_logs_days = 3 #意思是保留3天的binlog;默认值是0,表示不自动删除.备注:设置完该参数之后,当重启实例,或者刷新日志的时候,就会进行检查,然后删除3天之前的日志
2.测试在刷新日志的时候,触发删除
2.1查看当前系统中的二进制文件
[root@testvm data]# ls -ltr mysql-bin.*
-rw-r----- 1 mysql mysql 177 Jul 25 11:58 mysql-bin.000001
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000002
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000003
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000004
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000005
-rw-r----- 1 mysql mysql 154 Jul 25 12:17 mysql-bin.000006
-rw-r----- 1 mysql mysql 114 Jul 25 12:17 mysql-bin.index2.2修改系统时间为3天之后
[root@testvm data]# date -s "2018-07-28 12:15:00" Sat Jul 28 12:15:00 CST 2018 [root@testvm data]# clock -w
2.3执行flush logs刷新日志
[root@testvm data]# ls -ltr mysql-bin.*
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000002 #1这个日志已经被删除了.
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000003
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000004
-rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000005
-rw-r----- 1 mysql mysql 201 Jul 28 12:15 mysql-bin.000006
-rw-r----- 1 mysql mysql 154 Jul 28 12:15 mysql-bin.000007
-rw-r----- 1 mysql mysql 114 Jul 28 12:15 mysql-bin.index2.4查看文件时间,执行flush logs操作
[root@testvm data]# stat mysql-bin.000002 File: `mysql-bin.000002' Size: 201 Blocks: 8 IO Block: 4096 regular file Device: fd00h/64768d Inode: 276736 Links: 1 Access: (0640/-rw-r-----) Uid: ( 502/ mysql) Gid: ( 502/ mysql) Access: 2018-07-28 12:15:31.539000285 +0800 Modify: 2018-07-25 12:17:39.528999883 +0800 Change: 2018-07-25 12:17:39.528999883 +0800 [root@testvm data]# ls -ltr mysql-bin.* -rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000002 -rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000003 -rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000004 -rw-r----- 1 mysql mysql 201 Jul 25 12:17 mysql-bin.000005 -rw-r----- 1 mysql mysql 201 Jul 28 12:15 mysql-bin.000006 -rw-r----- 1 mysql mysql 201 Jul 28 12:17 mysql-bin.000007 -rw-r----- 1 mysql mysql 154 Jul 28 12:17 mysql-bin.000008 #这个生成时间减去标记为黄色的时间必须大于3天,黄色对应的文件才会被删除. -rw-r----- 1 mysql mysql 133 Jul 28 12:17 mysql-bin.index [root@testvm data]# date Sat Jul 28 12:18:08 CST 2018 [root@testvm data]# ls -ltr mysql-bin.* -rw-r----- 1 mysql mysql 201 Jul 28 12:15 mysql-bin.000006 -rw-r----- 1 mysql mysql 201 Jul 28 12:17 mysql-bin.000007 -rw-r----- 1 mysql mysql 201 Jul 28 12:18 mysql-bin.000008 -rw-r----- 1 mysql mysql 154 Jul 28 12:18 mysql-bin.000009 #18分执行的时候,3天前的17分的文件就都被删除了. -rw-r----- 1 mysql mysql 76 Jul 28 12:18 mysql-bin.index
备注:经过测试,就是,当刷新日志时(写满日志文件或者手动执行flush logs操作),在这个时间3天之前的binlog文件都会被删除.即执行刷新日志时,减去3天,binlog的时间小于这个的都会被删除.同时呢,当系统启动的时候也会执行flush logs操作,也会触发这个删除binlog的动作.
3.通过puge binary logs命令来进行删除
3.1查看当前binlog的信息
mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000006 | 201 | | mysql-bin.000007 | 201 | | mysql-bin.000008 | 201 | | mysql-bin.000009 | 201 | | mysql-bin.000010 | 201 | | mysql-bin.000011 | 201 | | mysql-bin.000012 | 201 | | mysql-bin.000013 | 201 | | mysql-bin.000014 | 201 | | mysql-bin.000015 | 201 | | mysql-bin.000016 | 201 | | mysql-bin.000017 | 201 | | mysql-bin.000018 | 201 | | mysql-bin.000019 | 201 | | mysql-bin.000020 | 201 | | mysql-bin.000021 | 154 | +------------------+-----------+ 16 rows in set (0.00 sec)
3.2purge删除binlog
mysql> purge binary logs to 'mysql-bin.000017'; Query OK, 0 rows affected (0.01 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000017 | 201 | | mysql-bin.000018 | 201 | | mysql-bin.000019 | 201 | | mysql-bin.000020 | 201 | | mysql-bin.000021 | 154 | +------------------+-----------+ 5 rows in set (0.00 sec)
备注:通过查询结果可以知道,在17之前的日志都被清除了.不包括17本身.切记!
4.切记不能在操作系统上直接删除binlog文件,虽然释放了空间,但是在Index中,还是有记录.
[root@testvm data]# ls -ltr mysql-bin.* -rw-r----- 1 mysql mysql 201 Jul 28 12:42 mysql-bin.000017 -rw-r----- 1 mysql mysql 201 Jul 28 12:42 mysql-bin.000018 -rw-r----- 1 mysql mysql 201 Jul 28 12:42 mysql-bin.000019 -rw-r----- 1 mysql mysql 201 Jul 28 12:42 mysql-bin.000020 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000021 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000022 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000023 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000024 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000025 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000026 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000027 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000028 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000029 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000030 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000031 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000032 -rw-r----- 1 mysql mysql 154 Jul 28 12:45 mysql-bin.000033 -rw-r----- 1 mysql mysql 323 Jul 28 12:45 mysql-bin.index [root@testvm data]# rm -f mysql-bin.000017 mysql-bin.000018 mysql-bin.000019 mysql-bin.000020 [root@testvm data]# ls -ltr mysql-bin.* -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000021 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000022 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000023 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000024 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000025 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000026 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000027 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000028 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000029 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000030 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000031 -rw-r----- 1 mysql mysql 201 Jul 28 12:45 mysql-bin.000032 -rw-r----- 1 mysql mysql 154 Jul 28 12:45 mysql-bin.000033 -rw-r----- 1 mysql mysql 323 Jul 28 12:45 mysql-bin.index
在mysql中查询binlog信息
mysql> show binary logs;
+------------------+-----------+
| Log_name | File_size |
+------------------+-----------+
| mysql-bin.000017 | 0 |
| mysql-bin.000018 | 0 |
| mysql-bin.000019 | 0 |
| mysql-bin.000020 | 0 |
| mysql-bin.000021 | 201 |
| mysql-bin.000022 | 201 |
| mysql-bin.000023 | 201 |
| mysql-bin.000024 | 201 |
| mysql-bin.000025 | 201 |
| mysql-bin.000026 | 201 |
| mysql-bin.000027 | 201 |
| mysql-bin.000028 | 201 |
| mysql-bin.000029 | 201 |
| mysql-bin.000030 | 201 |
| mysql-bin.000031 | 201 |
| mysql-bin.000032 | 201 |
| mysql-bin.000033 | 154 |
+------------------+-----------+
17 rows in set (0.00 sec)备注:还记录了文件的名字,但是文件的大小是0byte.
查看index中的记录信息
[root@testvm data]# cat mysql-bin.index ./mysql-bin.000017 ./mysql-bin.000018 ./mysql-bin.000019 ./mysql-bin.000020 ./mysql-bin.000021 ./mysql-bin.000022 ./mysql-bin.000023 ./mysql-bin.000024 ./mysql-bin.000025 ./mysql-bin.000026 ./mysql-bin.000027 ./mysql-bin.000028 ./mysql-bin.000029 ./mysql-bin.000030 ./mysql-bin.000031 ./mysql-bin.000032 ./mysql-bin.000033 [root@testvm data]#
备注:index中还是记录该信息,认为还是存在的.
重新启动的时候,会检查文件是否存在,如果不在会报错:
mysqld: File './mysql-bin.000017' not found (Errcode: 2 - No such file or directory) 2018-07-28T04:49:02.619409Z 0 [ERROR] Failed to open log (file './mysql-bin.000017', errno 2) 2018-07-28T04:49:02.619416Z 0 [ERROR] Could not open log file mysqld: File './mysql-bin.000018' not found (Errcode: 2 - No such file or directory) 2018-07-28T04:49:02.619426Z 0 [ERROR] Failed to open log (file './mysql-bin.000018', errno 2) 2018-07-28T04:49:02.619428Z 0 [ERROR] Could not open log file mysqld: File './mysql-bin.000019' not found (Errcode: 2 - No such file or directory) 2018-07-28T04:49:02.619436Z 0 [ERROR] Failed to open log (file './mysql-bin.000019', errno 2) 2018-07-28T04:49:02.619438Z 0 [ERROR] Could not open log file mysqld: File './mysql-bin.000020' not found (Errcode: 2 - No such file or directory) 2018-07-28T04:49:02.619445Z 0 [ERROR] Failed to open log (file './mysql-bin.000020', errno 2) 2018-07-28T04:49:02.619447Z 0 [ERROR] Could not open log file
备注:遇到这种问题,直接通过purge binary logs删除就行了.同时也会更新index文件
切记!!不要从操作系统上直接删除binlog!!!
文档创建时间:2018年7月19日16:02:00
