New devtool: timeline

156 views
Skip to first unread message

Paul Rouget

unread,
Sep 12, 2014, 5:39:39 AM9/12/14
to dev-...@lists.mozilla.org
Gaia people,

We are working on a new tool. A timeline.
Screenshot: http://i.imgur.com/D5i5Ghg.png

It records: reflow, restyle and paint.

To test it you need to use WebIDE in Firefox Nightly,
and have a very recent build on your device. In the
toolbox settings (gear on the right of the devtools),
you need to enable the timeline.

Known issues:
- iframes activity is ignored (bug 1050773)
- rare crashes (bug 1065122)
- some paint operations are duplicated (bug 1065954)
- some markers might be missed (bug 1050773)

Even though it's still in an early stage of development,
the timeline is useful as it is, and you might want to
give it a try, and we would like to get your feedback.

Please file bugs (Firefox > Developer Tools: Timeline).

Next:
- address mentioned issue
- add more data (compositing, requestAnimationFrame, DOM events, ...)
- merge timeline within the performance tab

Relevant bugs:
- http://bugzil.la/timeline
- http://bugzil.la/timeline-v1

-- Paul

Julien Wajsberg

unread,
Sep 15, 2014, 4:55:38 AM9/15/14
to dev-...@lists.mozilla.org
Hey Paul,

this looks awesome :)

Some questions and requests:
* can this record also during the initial load for an application?
* could this eventually record some event we have in the profiler,
especially IO ?

Thanks,
--
Julien
> _______________________________________________
> dev-gaia mailing list
> dev-...@lists.mozilla.org
> https://lists.mozilla.org/listinfo/dev-gaia


signature.asc

Paul Rouget

unread,
Sep 15, 2014, 6:01:21 AM9/15/14
to Julien Wajsberg, dev-...@lists.mozilla.org
Julien Wajsberg wrote:
> Hey Paul,
>
> this looks awesome :)
>
> Some questions and requests:
> * can this record also during the initial load for an application?

Start the timeline, record, then press "play" again. It will reload the app.

> * could this eventually record some event we have in the profiler,
> especially IO ?

Which events exactly?

> Le 12/09/2014 11:39, Paul Rouget a �crit :
-- Paul

Wilson Page

unread,
Sep 25, 2014, 11:57:38 AM9/25/14
to Paul Rouget, Julien Wajsberg, dev-...@lists.mozilla.org
This is great! I imagine a lot of work has gone into this. The tool tells us what has happened and when, but I haven't yet seen it tied events to the code that caused them. Will we be able to one day see that an 'expensive layout' or a 'crazy paint storm' was caused by 'line x'?

Regarding more event types/detail, I think we need to be careful to not overwhelm the user with data (a la current profiler). I'd love a way to 'dive deeper' if/when I need to :)

WILSON PAGE

Front-end Developer
Firefox OS (Gaia)
London Office

Twitter: @wilsonpage
IRC: wilsonpage


From: "Paul Rouget" <pa...@mozilla.com>
To: "Julien Wajsberg" <jwaj...@mozilla.com>
Cc: dev-...@lists.mozilla.org
Sent: Monday, September 15, 2014 11:01:21 AM
Subject: Re: New devtool: timeline


Julien Wajsberg wrote:
> Hey Paul,
>
> this looks awesome :)
>
> Some questions and requests:
> * can this record also during the initial load for an application?

Start the timeline, record, then press "play" again. It will reload the app.

> * could this eventually record some event we have in the profiler,
> especially IO ?

Which events exactly?

Paul Rouget

unread,
Sep 25, 2014, 1:08:37 PM9/25/14
to Wilson Page, Julien Wajsberg, dev-...@lists.mozilla.org
Wilson Page wrote:
> but I haven't yet seen it tied events to the code that caused them. Will we be able to one day see that an 'expensive layout' or a 'crazy paint storm' was caused by 'line x'?

Yes. We're working on that. Hope to get that done soon.

> Regarding more event types/detail, I think we need to be careful to not overwhelm the user with data (a la current profiler). I'd love a way to 'dive deeper' if/when I need to :)

Yes. Exactly. We plan to keep it simple. You will always be able to switch to
more advanced views: flame chart and call tree.
-- Paul
Reply all
Reply to author
Forward
0 new messages