MySQL Bugs: #70601: Dashboard: startup can be very slow, not clear when initialisation complete

Bug #70601	Dashboard: startup can be very slow, not clear when initialisation complete
Submitted:	11 Oct 2013 8:03	Modified:	9 Jan 2015 10:15
Reporter:	Simon Mudd (OCA)	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Enterprise Monitor: Server	Severity:	S3 (Non-critical)
Version:	3.0.2.2900	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
I have seen this on several occasions. The monitor startup can quite quite a long time. During this period there is a lot of logging, and it's not always easy to determine when it is completely initialised.
If the dashboard has a startup issue meaning the start up fails this is not obvious.

So adding a better status output indicator avoids the user having to wait an indeterminate period of time to see if the dashboard startup has worked correctly.

How to repeat:
see above.

Suggested fix:
Seen on MEM 2.x also.
From what I can see during startup the agents are able to connect to the http/https ports and thus start to trigger work. However during this time the dashboard is still initialising.

To speed up initialisation probably it might be better to not accept agent connections: tell them the dashboard is busy and to come back a random time later. (to avoid thundering herd issues)
For users, being able to login to the dashboard as soon as possible would be ideal but potentially the same message can be shown: "Dashboard initialisation in progress, please try again (in say 30 seconds)".

Provide some mechanism to easily see if the dashboard is initialised and running, perhaps via the mysqlmonitorctl.sh status output.