1302812 - Total URI Count shows different behavior when error page visited in different order

Status: RESOLVED DUPLICATE of bug 1293318

(Toolkit :: Telemetry, defect, P2)

Description

[John Dorlus [:Silne30]]

Scenario 1:

While validating if total_uri_count performs correctly, I noticed a small difference in an edge case. Can you tell me what behavior is desired. 

Steps to reproduce:
1.) Open up nightly with new profile
2.) In the first tab, navigate to about:telemetry and expand the Scalars section. They should read: 
Name: browser.engagement.total_uri_count, Value: 1
Name: browser.engagement.max_concurrent_window_count, Value:1
Name: browser.engagement.unique_domains_count, Value: 1
Name: browser.engagement.max_concurrent_tab_count, Value: 2

3.) Go to the other tab and navigate to about:nobody (It's a fake page, should throw error)
4.) Go back to about:telemetry Tab and refresh. The scalars should not change.

Scenario 2:
Steps to reproduce:
1.) Open up nightly with new profile
2.) In the first tab: navigate to about:nobody
3.) In the second tab: navigate to about:telemetry and expand the scalars section.
4.) The scalars are different from the above scenario. They now read:
Name: browser.engagement.max_concurrent_window_count, Value:1
Name: browser.engagement.max_concurrent_tab_count, Value: 2

Which is correct?

Comment 1

[Alessio Placitelli [:Dexter]]

(In reply to John Dorlus [:Silne30] from comment #0)
> Scenario 2:
> Steps to reproduce:
> 1.) Open up nightly with new profile
> 2.) In the first tab: navigate to about:nobody
> 3.) In the second tab: navigate to about:telemetry and expand the scalars
> section.
> 4.) The scalars are different from the above scenario. They now read:
> Name: browser.engagement.max_concurrent_window_count, Value:1
> Name: browser.engagement.max_concurrent_tab_count, Value: 2
> 
> Which is correct?

Mh, that's a very interesting issue. I claim the first scenario is the correct one, as "about:nobody" should not be counted as a loaded URI.

I can't seem to reproduce the second scenario. What's the build id of the nightly you're using? What platform are you on?

Comment 2

[John Dorlus [:Silne30]]

Build ID: 20160916030204
Platform: Mac OSX 10.11.6

I was just able to reproduce it again.

Comment 3

[Alessio Placitelli [:Dexter]]

So, it looks like I can reproduce the same behaviour on my machine, but in a different way.

STR

- Open nightly with a fresh profile
- Open some new URIs
- Open a new tab with about:telemetry
- Wait for Telemetry to init (60s from startup).
- Refresh the about:telemetry page: the total_uri count in the Scalars section will be missing.

This seems to only happen on the very first run of Firefox, because some module is flipping a preference, and a new subsession is created right after the startup. This clears the scalars.

This is going to be fixed by bug 1293318.

Comment 4

[Alessio Placitelli [:Dexter]]

Closing this as a duplicate of bug 1293318.