MySQL TroubleShoting：无任何操作、磁盘I/O负载跑满-Mysql Tutorial-php.cn

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MySQL TroubleShoting：无任何操作、磁盘I/O负载跑满

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Jun 07, 2016 pm 04:14 PM

mysqloperatedisk

㈠环境： OS : RHEL-5.8 Server：MySQL 5.5 Engine：InnoDB ㈡问题：在无任何操作的前提下、磁盘IO负载都几乎跑满、然后跑了3、4个小时磁盘负载依旧 iotop 部分输出： Total DISK READ: 32.55 M/s | Total DISK WRITE: 0.00 B/sTID PRIO USER DISK READ D

㈠环境：

OS : RHEL-5.8
Server：MySQL 5.5
Engine：InnoDB

㈡问题：

在无任何操作的前提下、磁盘IO负载都几乎跑满、然后跑了3、4个小时磁盘负载依旧

iotop 部分输出：

Total DISK READ: 32.55 M/s | Total DISK WRITE: 0.00 B/s
TID  PRIO  USER     DISK READ  DISK WRITE  SWAPIN     IO>    COMMAND
535  be/4 mysql       3.26 M/s    0.00 B/s  0.00 % 80.88 % mysqld --basedir=...
536 be/4 mysql      29.26 M/s    0.00 B/s  0.00 % 71.93 % mysqld --basedir=...
......

㈢现象：

做sysbench的全update性能测试、测试完成后就关闭了数据库
但是当再重启后就发现这个现象、并且等待3、4个小时候后问题依旧

㈣原因：

innodb_fast_shutdown 被设置为1 引起的

        ① innodb_fast_shutdown ==> 1:关闭时不进行change buffer的merge操作以及purge操作、而是在下一个开机周期进行
        ② innodb_fast_shutdown ==> 0：将merge change buffer和purge的操作时间放在了关闭数据库的时候做

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