1233323 - load and DOMContentLoaded marker are not displayed when performance is recorded

Status: REOPENED

(DevTools :: Netmonitor, defect, P3)

Description

[Sebastian Zartner [:sebo]]

When a performance profile is created while the page is loaded, the markers for the 'load' and 'DOMContentLoaded' events are not added to the Network panel.

STR:
1. On this page open the Performance panel
2. Click the 'Start Recording Performance' button
3. Reload the page
4. Switch to the Network panel

=> The line for the 'load' and 'DOMContentLoaded' events are not shown.

Sebastian

Comment 1

[Jordan Santell [:jsantell] [@jsantell]]

Bug 859042 is for displaying those markers in the performance tool -- the netmonitor doesn't use markers, but has vertical red and blue lines for these events. If I'm misunderstanding, please reopen. Thanks!

Comment 2

[Sebastian Zartner [:sebo]]

(In reply to Jordan Santell [:jsantell] [@jsantell] (Please needinfo) from comment #1)
> the netmonitor doesn't use markers, but has vertical red and blue lines for
> these events. If I'm misunderstanding, please reopen. Thanks!

I meant those vertical lines and regarding https://hg.mozilla.org/mozilla-central/rev/096b5587a7fa those are called markers within the code, too.

Anyway, disregarding the terminology, I reopen this, as it is a bug in the Network panel related to the performance recording. Though I have removed the reference to bug 859042.

Sebastian

Comment 3

[Jordan Santell [:jsantell] [@jsantell]]

Oh I see what you mean. I'm not sure if it's related to the performance recording, but on nightly, I do not consistently get both load and DOMContentLoaded markers in the netmonitor.

Comment 4

[Sebastian Zartner [:sebo]]

(In reply to Jordan Santell [:jsantell] [@jsantell] (Please needinfo) from comment #3)
> Oh I see what you mean. I'm not sure if it's related to the performance
> recording, but on nightly, I do not consistently get both load and
> DOMContentLoaded markers in the netmonitor.

Right, that's what I see, too. Sometimes they are both there, sometimes only one and sometimes none. Though this only happens for me when a performance recording is happening while the page loads. If no recording is running, I always get both displayed. So I assume it must be related to the recording.

Sebastian

Comment 5

[Jan Honza Odvarko [:Honza] (always need-info? me)]

(In reply to Jordan Santell [:jsantell] [@jsantell] (Away from Bugzilla for awhile) from comment #3)
> I do not consistently get both load and DOMContentLoaded markers in the netmonitor.
Both markers should be more stable after Bug 1309866 lands.

But, I can still clearly reproduce the issue - not seeing the markers if the Performance panel is recording during the page load.

@Jarda: is the Net panel receiving the "doc-loading" event from the Timeline actor in case the Performance panel is recording?

Honza

Comment 6

[Jarda Snajdr [:jsnajdr]]

When Performance and Netmonitor tools are running, they both create their own instance of performance/timeline actor.

That actor should be a singleton, though. It gets the timeline data by calling docShell.popProfileTimelineMarkers() at regular intervals. When there are two instances running, they steal pieces of the timeline data from each other.

Apparently, the Performance tool instance wins most of the time and Netmonitor doesn't get its doc-loading events.