1540388 - So much CPU usage running Firefox, the fan is at maximum

Status: RESOLVED WORKSFORME

(Core :: Performance: General, defect, P3)

Description

[Jean-Philippe MENGUAL]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

Using nightly, at running, the fan accelerates. And no longer becomes normal. The bug has been come since 10 days.

Actual results:

In top utility, I see 2 processes:
firefox-bin is 107%
Webextensions is 74%
Web content 40%, 21% and 20% (three processes)

URL of the Firefox mozilla:
https://profiler.firefox.com/from-addon/calltree/?globalTrackOrder=0-1-2-3-4-5&hiddenGlobalTracks=1-2-3&thread=5&v=3

Comment 1

[Daniel Holbert [:dholbert]]

(In reply to Jean-Philippe MENGUAL from comment #0)

URL of the Firefox mozilla:
https://profiler.firefox.com/from-addon/calltree/?globalTrackOrder=0-1-2-3-4-5&hiddenGlobalTracks=1-2-3&thread=5&v=3

Hello! Thanks for capturing a profile. Unfortunately, this ^^ URL is for a view of a local profile (i.e. it wasn't shared), so we aren't able to view it. (The "from-addon" in the URL means it's viewing locally stored data that was just captured from the profiler add-on.)

If you can still reproduce the bug, would you mind recapturing a profile and hitting the "Publish" button at the top right of the final profile page, to get a short-link?

Comment 2

[Jean-Philippe MENGUAL]

Hi,

Thanks for this feedback. The bad news i that the profile is few accessible and it is a pain to understand and run it properly. The good news is that the bug seems fixed.

The thing is not clear for me: it seems to be due to an addon, stylish. But playing with enabling/disabling this one, it ends-up working / re-spending CPU. So not totally clear, but I really think this or another addon is responsible (I have very few addons)

I dont know hw you want to close the bug, but I think we can now. I note your feedback for futur performance issues in Nightly

Regards

Comment 3

[Daniel Holbert [:dholbert]]

Thanks for that information. We'd still be interested in investigating a bad interaction with Stylish, since it's got a decent number of users and we don't want those users to have a bad Firefox experience. In fact, I myself have Stylish installed, though I haven't seen the CPU-usage issue that you mentioned here.

Is there any chance that you could provide steps that make the issue reproduce, with Stylish installed (including which stylish rules you have applied [if any] on the page that you're viewing when the problem happens)?

Also, a Firefox profile would be very helpful here to see what we (or Stylish) are doing with all those CPU cycles. You mentioned that it's a bit difficult to understand -- we're working to make it easier to use, but for now, the steps are:
(1) install the profiler addon from https://profiler.firefox.com/
(2) Close as many background tabs as possible, to minimize data that's captured & reduce noise.
(3) Just before triggering the problem (or while the problem is happening), Ctrl+Shift+1 to start profiling
(4) After you've reproduced the problem, Ctrl+Shift+2 to capture the profile and open up the profiler UI webpage.
(5) Click the "publish" button at the top right of the profiler UI webpage, and tick checkboxes to indicate whether you'd like to redact the list of URLs that you had open etc.
(6) Post the "published" URL here.

(I think you already did most of these steps when you initially reproduced the bug, except for the "publish" step.)

Comment 4

[alex_mayorga]

¡Hola Jean-Philippe!

Is this still an issue on a current Firefox Nightly install, please?

You can get the Firefox Nightly installer from https://nightly.mozilla.org/

If so, please capture a profile as detailed at https://profiler.firefox.com/

¡Gracias!
Alex

Comment 5

[Jean-Philippe MENGUAL]

Hi

I use Nightly everyday. Since I Have disabled Stylish plugin, I no longer reproduce, even re-enabling it. Sà I think this bug can be considered as fixed.

Thanks

regards

Comment 6

[alex_mayorga]

¡Hola Jean-Philippe!

Thanks for getting back!

Marking as FIXED per your most recent response.

Please go to https://bugzilla.mozilla.org/show_bug.cgi?id=1540388 and set it to VERIFIED whenever you get a chance.

¡Gracias!
Alex

Comment 7

[Daniel Holbert [:dholbert]]

--> Relaxing the bug-resolution to "WORKSFORME" rather than "FIXED", since we don't know for sure that any code-change happened that would've fixed this. All we know is that the reporter can't reproduce anymore (possibly due to disabling the Stylish add-on) -- and that's still good news. :)