Bug #31842 graphs 'database activity' have no vertical scale < 1
Submitted: 25 Oct 2007 10:38 Modified: 11 Oct 2010 13:30
Reporter: Carsten Segieth Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Enterprise Monitor: Server Severity:S3 (Non-critical)
Version:1.2.0.7854, 2.0 OS:Any
Assigned to: Josh Sled CPU Architecture:Any

[25 Oct 2007 10:38] Carsten Segieth 
Description:
I see no vertical scale (only) in the 'database activity' graphs of a MySQL 4.1.23-pro-gpl-nt-log, both on the dashboard and on the graphs page (see attached screen shots). All other graphs have the vertical scale as expected.

It occures with 3 different agents (7657, 7757, 7854) connected to the server.

server data:
https://intranet.mysql.com/~csegieth/merlin/net-qa1_2007-10-25-11.12.28_dump.tgz
https://intranet.mysql.com/~csegieth/merlin/net-qa1_2007-10-25-11.12.28_logs.tgz

How to repeat:
start agent against a 4.1.23 mysqld (which in this case has binlog enabled, not sure this is relevant ...)

Suggested fix:
show vertical scale
[25 Oct 2007 11:40] Carsten Segieth 
detected, that it also occurs whith a 4.0 server
[26 Oct 2007 0:13] Bill Weber 
What I think is happening is that the values per heartbeat are less than 60. For the DB Activity graph (and others) the values are avg/sec so they're divided by 60 and will be between 0 and 1. In that case we don't show the "1" tick mark line on the graph and it therefore appears like there is no vertical scale. If you look at some of the other graphs on the Graphs tab for this agent on net-qa1 (ie InnoDB OS File Access, InnoDB Row Details) that are avg x/sec, you'll see the same thing.

If this is the case, I suggest showing the "1" tick mark line to avoid confusion.
[13 Nov 2007 18:34] Joshua Ganderson 
After speaking with Oldag, his feeling is that this is just a lack of DB activity and shortcomings of jfreechart. Diagnosis - ignore until we can make better graphing than jfreechart allows for.
[13 Nov 2007 18:40] Joshua Ganderson 
In talking with Oldag, it came up that we enforce integral values in graphing. Apparently this is legacy code from when everything _would_ be a round number. Since we now do things like divide by 60, perhaps it's time to drop that constraint?
[23 Jun 2008 18:17] Eric Herman 
re-assingning Ganderson's bugs.
[30 Jul 2008 14:03] Sloan Childers 
No units are shown on the Y-axis for the new Load Average graph (actually, 0 is shown for the lower bound, but no upper bound is shown).
[23 Jan 2009 6:57] Valeriy Kravchuk 
Bug #42234 was marked as duplicate of this one.
[11 Oct 2010 13:30] Mark Leith 
For values below 0 I now see fractional values, for instance I can see a scale from 0.000 up to 0.125 avg/statements sec. 

Closing, as resolved now (and has been for some time).