Bug #89460 documentation lists incorrect innodb_flush_method=O_Direct my.cnf setting

• Submitted: 29 Jan 2018 19:47
• Modified: 30 Jan 2018 3:47
• Reporter: Pete Ditmars
• Status: Verified
• Category: MySQL Enterprise Monitor: Documentation
• Severity: S3 (Non-critical)
• Version: 4.0
• OS: Any
• CPU Architecture: Any

[29 Jan 2018 19:47] Pete Ditmars

Description:
The documentation here 
https://dev.mysql.com/doc/mysql-monitor/4.0/en/repository-prereq-reference.html

states:

 On Linux/Unix hosts, ensure innodb_flush_method=O_Direct, except on Solaris if ZFS is used. If using ZFS, comment out this parameter. 

However, it should state innodb_flush_method=O_DIRECT.  Using 0_Direct (bumpy case) as in the documentation results in this:

2018-01-29T20:15:54.699316Z 0 [Note] InnoDB: Using Linux native AIO
2018-01-29T20:15:54.699336Z 0 [ERROR] InnoDB: Unrecognized value O_Direct for innodb_flush_method
2018-01-29T20:15:54.699349Z 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error
2018-01-29T20:15:54.699364Z 0 [ERROR] Plugin 'InnoDB' init function returned error.
2018-01-29T20:15:54.699372Z 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2018-01-29T20:15:54.699381Z 0 [ERROR] Failed to initialize plugins.

How to repeat:
Edit my.cnf as indicated, add innodb_flush_method=O_Direct to the [mysqld] section, stop and restart your mysql instance.

Suggested fix:
 On Linux/Unix hosts, ensure innodb_flush_method=O_DIRECT, except on Solaris if ZFS is used. If using ZFS, comment out this parameter.

[30 Jan 2018 3:47] MySQL Verification Team

Hello Pete,

Thank you for the report and feedback.

Thanks,
Umesh