Bug #88359 Documentation about mysqld-debug should mention plugin_dir
Submitted: 4 Nov 2017 11:34 Modified: 22 Nov 2017 20:46
Reporter: Daniël van Eeden (OCA) Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:5.7.20 OS:Any
Assigned to: CPU Architecture:Any

[4 Nov 2017 11:34] Daniël van Eeden 
Description:
Page: https://dev.mysql.com/doc/refman/5.7/en/linux-installation-rpm.html

"Debug Package.  A special variant of MySQL Server compiled with the debug package has been included in the server RPM packages. It performs debugging and memory allocation checks and produces a trace file when the server is running. To use that debug version, start MySQL with /usr/sbin/mysqld-debug, instead of starting it as a service or with /usr/sbin/mysqld. See Section 28.5.3, “The DBUG Package” for the debug options you can use."

This doesn't say:
- That the plugin_dir should be set to something like /usr/lib64/mysql/plugin/debug/ instead of the default of /usr/lib64/mysql/plugin/
- That it is possible to change the systemd config to use an alternative ExecStart

Related: Bug #88088

How to repeat:
See description
[4 Nov 2017 11:52] Daniël van Eeden 
Related:
Bug #88363 	Default plugin_dir should be different for debug build
[4 Nov 2017 11:55] Daniël van Eeden 
Related:
Bug #88363
Bug #88362
Bug #88361
Bug #88360
[4 Nov 2017 15:00] MySQL Verification Team 
Thank you for the bug report.
[22 Nov 2017 20:46] Philip Olson 
Posted by developer:
 
This is now documented, for example in the 8.0 manual as:

  The default plugin directory for debug builds changed from
  /usr/lib64/mysql/plugin to /usr/lib64/mysql/plugin/debug
  in 8.0.4. Previously, manually changing plugin_dir was required.

The bug fix (this change) was tracked in Bug #88363 (another bug you filed, thanks!) 

Thank you for the bug report.