MySQL Bugs: #80248: Confusing "Number of pools: 1" message on InnoDB startup

Bug #80248	Confusing "Number of pools: 1" message on InnoDB startup
Submitted:	3 Feb 2016 8:48	Modified:	9 Aug 2022 18:54
Reporter:	Alexey Kopytov	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: InnoDB storage engine	Severity:	S3 (Non-critical)
Version:	5.7, 5.7.12	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
Noticed the following message on server startup, which made me wondering
if I had misconfigured innodb_buffer_pool_instances, or it was referring
to something else:

[Note] InnoDB: Number of pools: 1

It turns out that message refers to the number of abstract object pools
implemented in ut0pool.h, which is currently only used by the
transaction pool in trx0trx.cc. But it's impossible to figure that out
without reading the source code.

It is confusing and I'm not sure a low-level code like that should be
that chatty. Can that message be removed, or at least made more
specific?

How to repeat:
Check the error log on server startup.

Hello Alexey,

Thank you for the report.

-- with 5.7.12

2016-01-27T08:50:15.192129Z 0 [Note] bin/mysqld-debug (mysqld 5.7.12-enterprise-commercial-advanced-debug-log) starting as process 7796 ...
.
.
.
2016-01-27T08:50:15.199836Z 0 [Note] InnoDB: Using Linux native AIO
2016-01-27T08:50:15.200335Z 0 [Note] InnoDB: Number of pools: 1

Thanks,
Umesh

Posted by developer:
 
Fixed as of the upcoming 8.0.31 release:

An InnoDB startup message that specified the number of object pools was
removed to avoid confusion with the number of buffer pool instances.