MySQL Bugs: #61277: Innodb "old database pages" aren't collected by MEM

Bug #61277	Innodb "old database pages" aren't collected by MEM
Submitted:	24 May 2011 15:50	Modified:	22 Sep 2014 10:53
Reporter:	Ben Mildren	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Enterprise Monitor: Server	Severity:	S3 (Non-critical)
Version:	MEM 2.3, MySQL 5.5	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	global status, innodb status

Description:
In MySQL 5.5, the "Buffer Pool and Memory" section of SHOW INNODB ENGINE STATUS, now reports "Old database pages" separately to "Database pages".

MEM collects "Database pages" using SHOW INNODB ENGINE STATUS it doesn't however seem to collect "Old database pages". This leads to confusion when looking at the InnoDB Buffer Pool graph.

MEM also collects "Database pages" using the GLOBAL STATUS VARIABLES, interestingly though "Old database pages" seems to be reported as part of Innodb_buffer_pool_pages_misc.

How to repeat:
MEM Help File:

Appendix D. Data Collection Items

...

mysql innodbstatus innodb_bp_db_pages long The current number of buffer pool pages
mysql innodbstatus innodb_bp_dictionary_alloc long MISSING
mysql innodbstatus innodb_bp_free_buffers long The current number of free buffer pool pages
(No "Old database pages" collection specified)

...

Appendix B.

innodb_buffer_pool.name

Displays the size and page usage of the InnoDB buffer pool, providing information on the cache usage and performance. The graph shows the buffer pool size, active pages, and the number of modified pages.
Name innodb_buffer_pool.name
Range Label innodb_buffer_pool.rangeLabel
Series Expression
innodb_buffer_pool.series1.label (size*16384)/(1024*1024)
innodb_buffer_pool.series2.label (used*16384)/(1024*1024)
innodb_buffer_pool.series3.label (modified*16384)/(1024*1024)
innodb_buffer_pool.series4.label (dict)/(1024*1024)
Variables Data Item
size mysql:innodbstatus:innodb_bp_size
used mysql:innodbstatus:innodb_bp_db_pages
modified mysql:innodbstatus:innodb_bp_modified_pages
dict mysql:innodbstatus:innodb_bp_dictionary_alloc

(Confirms use of innodbstatus db_Pages collection, highlighting the absence of "Old database pages")

Suggested fix:
Add collection for "Old database pages" from innodbstatus.

Add global status variable for "Old database pages", or choose to include "Old database pages" in Innodb_buffer_pool_pages_data as opposed to Innodb_buffer_pool_pages_misc.

Thank you for the problem report.

Added to 2.3.5 change log:

Added the following new InnoDB-related items to graphs:

Added an Old series to the InnoDB Buffer Pool graph. Added a Redo Log series to
the InnoDB OS File Access graph. New graph InnoDB Buffer Pool Page
Activity. New graph InnoDB Buffer Pool Pending Operations. New graph
InnoDB Change Buffer Usage. New graph InnoDB Change Buffer Activity
(two graphs, pre and post 5.5 versions). New graph InnoDB Doublewrite
Buffer Activity. New graph InnoDB Redo Log Pending Writes.