Bug #71671 No mention of cases where innodb monitor is auto-enabled?
Submitted: 11 Feb 2014 13:13 Modified: 4 Apr 2014 14:35
Reporter: Hartmut Holzgraefe Email Updates:
Status: Closed Impact on me:
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:* OS:Any
Assigned to: Daniel Price CPU Architecture:Any

[11 Feb 2014 13:13] Hartmut Holzgraefe
E.g. when semaphore wait time exceeds a certain limit the monitor output to the error log is temporarily enabled even if no innodb_monitor table exists:

  InnoDB: ###### Starts InnoDB Monitor for 30 secs to print diagnostic info:

but I can't find any mention of that on   


or anywhere else in the manual?

How to repeat:

Suggested fix:
[11 Feb 2014 15:25] MySQL Verification Team
This situation has indeed not been covered in our documentation !!!
[4 Apr 2014 14:35] Daniel Price
InnoDB automatically enables the InnoDB Monitor temporarily under the following conditions:

(1) Long semaphore wait (storage/innobase/sync/sync0arr.cc)
(2) When InnoDB cannot find free blocks in the buffer pool (storage/innobase/buf/buf0lru.cc)
(3) When over 67% of the buffer pool is occupied by lock heaps or the adaptive hash index (storage/innobase/buf/buf0lru.cc) 

The following pages have been updated for 5.0 through 5.7 of the reference manual. The revised content will appear soon, with the next published documentation build.


Thank you for the bug report.