Bug #80248 Confusing "Number of pools: 1" message on InnoDB startup
Submitted: 3 Feb 2016 8:48 Modified: 3 Feb 2016 8:53
Reporter: Alexey Kopytov Email Updates:
Status: Verified Impact on me:
Category:MySQL Server: InnoDB storage engine Severity:S3 (Non-critical)
Version:5.7, 5.7.12 OS:Any
Assigned to: CPU Architecture:Any

[3 Feb 2016 8:48] Alexey Kopytov
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

How to repeat:
Check the error log on server startup.
[3 Feb 2016 8:53] MySQL Verification Team
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