Bug #18669 Session COM_STATISTICS breaks mysqladmin status
Submitted: 31 Mar 2006 0:22 Modified: 31 May 2006 3:18
Reporter: Kolbe Kegel
Status: Closed
Category:Server Severity:S3 (Non-critical)
Version:5.0,5.1 OS:Linux (Linux)
Assigned to: Iggy Galarza Target Version:

[31 Mar 2006 0:22] Kolbe Kegel 
Description:
COM_STATISTICS was changed in 5.0 to show session statistics instead of global statistics
as it had done in previous versions.

This change has the effect of making "mysqladmin status" show essentially useless
information, specifically as related to "Slow queries" and "Opens".

Presumably, mysqladmin will always report 0 for both of these values, as getting status
information with mysqladmin will never itself trigger a Slow query or Open.

How to repeat:
Execute several slow queries in both 4.1 and 5.0 and use "mysqladmin status" to see
server status information.

From 5.0.20-bk:

Uptime: 899  Threads: 2  Questions: 79  Slow queries: 0  Opens: 0  Flush tables: 1  Open
tables: 11  Queries per second avg: 0.088

From 4.1.18:

Uptime: 773  Threads: 1  Questions: 52  Slow queries: 2  Opens: 19  Flush tables: 1  Open
tables: 11  Queries per second avg: 0.067

Suggested fix:
COM_STATISTICS should be changed in 5.1 to return GLOBAL status information rather than
session information. Alternatively, some other interface could be added so that both
global and session status information was available.
[22 May 2006 23:23] Bugs System 
A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/6739
[24 May 2006 15:34] Bugs System 
A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/6833
[30 May 2006 16:16] Iggy Galarza 
Fixed in upcoming release 5.0.23.
[31 May 2006 3:18] Paul DuBois 
Noted in 5.0.23 changelog.

The COM_STATISTICS command was changed in 5.0.3 to display session
status variable values rather than global values. This causes
mysqladmin status information not to be useful for the Slow queries
and Opens values. Now COM_STATISTICS displays the global values for
Slow queries and Opens.