MySQL Bugs: #42162: Graph on the dashboard are not always refreshed/updated

Bug #42162	Graph on the dashboard are not always refreshed/updated
Submitted:	16 Jan 2009 15:48	Modified:	4 Mar 2009 11:02
Reporter:	Diego Medina	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Enterprise Monitor: Web	Severity:	S2 (Serious)
Version:	2.0.2.7128	OS:	Any
Assigned to:	MC Brown	CPU Architecture:	Any

Description:
Some graph on the "graph tab" are not refreshed on the UI after you refresh the page, or hit "update" on the graph tab

The only way to get an updated graph is to change the graph size (pixels) and then click on "update"

How to repeat:
1- Install and start the service manager and agent
2- go to the graph tab and set the refresh interval of the page to "30 seconds"
3- wait a few minutes and you will notice that then "time range" is not being updated, hence showing "old" data

I can definitely see the issue in the liveHTTP log.  Requests will come across for the actual graph images/pngs with the request headers [[[
If-Modified-Since: Tue, 27 Jan 2009 22:15:18 GMT

If-None-Match: W/"4853-1233094518000"

Cache-Control: max-age=0

]]]

But the response looks like [[[
HTTP/1.x 304 Not Modified

Server: Apache-Coyote/1.1

Cache-Control: max-age=60, must-revalidate

Etag: W/"4853-1233094518000"

Date: Tue, 27 Jan 2009 22:30:45 GMT

]]]

Note the Date on the response is *well* past the 5 minutes after which the server should forcibly remove the cached image data.

I just pulled Firefox 3.0.5 out of mothballs, and attempted to reproduce the issue, but failed.  As soon as the 10th 30-second-auto-refresh (5 minutes) comes along, the graphs are re-requested, and the server returns "200 (OK)" with the new image data and an updated timestamp.  After 9 more 304 (not modified) responses 4.5 minutes, the 10th response again returns correctly.

Ligaya, please obtain the following from the customer, all as near in time to each other as possible:

- A timestamp from the footer of MEM, and the server-configured timezone.

- The value (including timezone) of the system clock on the machine on which MEM is installed.

- The directory listing (including timestamps) of the "./web/graphs/" directory underneath the MEM install.

Hmm.  The timestamps do all line up.  I was hoping for somethign to be amiss there.

Okay, let's try having the customer reproduce after disabling all their Firefox extensions.

Also, please verify that there are no HTTP proxies (configured or invisible reverse proxies) in the customer's network.

branches/2.0/ only:

revno: 6602
revision-id: jsled@asynchronous.org-20090225204625-to5mk2ik44fan4xo
parent: jsled@asynchronous.org-20090223201755-hkmr317r0m35usp1
committer: Josh Sled <jsled@asynchronous.org>
branch nick: 2.0
timestamp: Wed 2009-02-25 15:46:25 -0500
message:
  Bug#42162: use the correct (GMT-millis-since-epoch, not user-dependent) time value for on-filesystem Graph cache expiration check.

Patch installed in versions => 2.0.5.7146.

Verified fixed on 2.0.5.7146

An entry was added to the 2.0.5 changelog:

Some graphs on the Graph tab were not updated after the page was refreshed, or Update was clicked.

The only way to get an updated graph was to change the graph size (in pixels) and then click Update.