Bug #85686 [Warning] option 'performance_schema_max_statement_classes': value -1 adjusted t
Submitted: 29 Mar 2017 14:08 Modified: 27 Oct 2017 17:21
Reporter: kfpanda kf Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:5.7.17 OS:Any
Assigned to: CPU Architecture:Any

[29 Mar 2017 14:08] kfpanda kf
Description:
Hello,
 It'is said that the default value of variable performance_schema_max_statement_classes is -1(autosized).
https://dev.mysql.com/doc/refman/5.7/en/performance-schema-system-variables.html#sysvar_pe...

firet,i add "performance_schema_max_statement_classes=-1" into my.cnf(section: mysqld)

then,i restart mysql, warning occurs in error log:
2017-03-29T13:59:04.423327Z 0 [Warning] option 'performance_schema_max_statement_classes': value -1 adjusted to 0

How to repeat:
firet,i add "performance_schema_max_statement_classes=-1" into my.cnf(section: mysqld)

then,i restart mysql, warning occurs in error log:
2017-03-29T13:59:04.423327Z 0 [Warning] option 'performance_schema_max_statement_classes': value -1 adjusted to 0

Suggested fix:
I hope  that it is  to autosize the vale of performance_schema_max_statement_classes when i set performance_schema_max_statement_classes -1.
[29 Mar 2017 15:58] MySQL Verification Team
Hi!

I have done a clean installation and this is truly a bug in our manual. After my clean install, without changing any values , I get this from the output of all values in performance_schema::

 performance_schema_max_statement_classes                 | 193  

Hence, our documentation requires a correction.
[27 Oct 2017 17:21] Paul DuBois
Posted by developer:
 
-1 is the default value for this and similar Performance Schema parameters. You don't need to set it. Leave the value unset at server startup and the Performance Schema autosizes itself.