MySQL Bugs: #111038: Extend documentation about innodb_flush_sync wrt to innodb_io_capacity

Bug #111038	Extend documentation about innodb_flush_sync wrt to innodb_io_capacity_max
Submitted:	16 May 2023 0:40	Modified:	21 Mar 2024 21:17
Reporter:	Wiebe Cazemier	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	8.0	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
The documentation for 'innodb_flush_sync' or 'innodb_io_capacity_max' don't mention each other, so it's not clear whether 'innodb_flush_sync' also ignores 'innodb_io_capacity_max'.

The source code does seem to mention it in "https://github.com/mysql/mysql-server/blob/e57893fef5b2739c59b8f354d199251514571f61/storag...".

"This should force page cleaners to perform the sync-flush in which case the innodb_max_io_capacity is not respected."

Although it's a big ambiguous, because 'innodb_max_io_capacity' is worded differently, and not sure if it's talking about 'innodb_io_capacity_max'.

How to repeat:
Read:

https://dev.mysql.com/doc/refman/8.0/en/innodb-configuring-io-capacity.html

Suggested fix:
The option 'innodb_flush_sync' should mention whether 'innodb_io_capacity_max' is also ignored.

The 'innodb_io_capacity_max' option should also mention the reverse.

Hello Wiebe Cazemier,

Thank you for the report and feedback.

regards,
Umesh

Posted by developer:
 
Thank you for the bug report, this is now documented. It was referring to innodb_io_capacity_max as innodb_max_io_capacity was the original name of this option before being renamed long ago.