1724200 - My CPU locks up (goes to 100%) with at least two websites that I frequently use, ever since Version 90.0.2 (Linux 64 bit) was installed in July 2021..

Status: RESOLVED INCOMPLETE

(Core :: Performance: General, defect)

Description

[Jess Weil]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:90.0) Gecko/20100101 Firefox/90.0

Steps to reproduce:

I click on something in the website I'm using to get to the place where I can use the website, e.g. order some food or add an address to my email whitelist. I've reproduced the problem several times with the exact same actions. Other actions do not cause it. I have a Kubuntu operating system (18.04 or newer) on a one year old ASUS PC. I did not have this problem until after Firefox Version 90.0.2 was installed on my PC in late July, so I suspect a bug. The administrator at the mail server website where I have the problem has checked for a problem there, and suggests it may be a Firefox bug.

Actual results:

I have a four kernel CPU, and immediately one kernel goes to 100% usage and I cannot enter any more information. The PC does not respond to the keyboard or mouse. My System Monitor shows this behavior both graphically and in a list of processes. The Process Table says a process labelled Web is fully using one kernel (i.e. 25% CPU usage). I have kill that process in the System Monitor window to regain the ability to use the keyboard or mouse.

Expected results:

I should have been able to use the keyboard and/or mouse to enter information on the website, or navigate on it.

Comment 1

[Clara Guerrero ( Need Info Brindusa Tot Please)]

Hi!
Can you attach your about:support information please?
It would help us if you can provide a memory report from about:memory, here are the steps for you to get it:

In the URL bar type about:memory and press enter
Click ""Measure and save"" (optionally with ""anonymize"" checked to hide URLs, although this will likely make it more difficult for us to figure out which site, if any, is causing the leak)
Save the memory report somewhere
Attach the report to this bug

Also it would help us a lot if you could reproduce this issue on our latest Nightly build, it can be downloaded from here: https://nightly.mozilla.org/
Then capture a performance profile using
https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Profiling_with_the_Built-in_Profiler
https://perf-html.io/
Please also note that this add-on works only on FF Nightly, so that means you need to be able to reproduce the issue on Nightly first.

Best,
Clara

Comment 2

[Jess Weil]

Dear Clara;
I tried to send this yesterday as a reply email to bugzilla-daemon, but it bounced back, so I realized I have to reply to you some other way. Both with Add Comment, and using the reply arrow on your message to me. Which is the best way for the future? LATER. I see the Reply arrow is the best way since it gives a copy of what I'm replying to.

 Thanks for your reply. I'm glad you are going to try to sort this out.

Unfortunately, I'm leaving on two weeks vacation on Sunday, and won't be using
my computer most likely while away.
I have done the about:memory task and attached the output to the bug
report. And I downloaded the latest nightly build, and have it in
my Downloads. But I'm not very computer able, and don't know what to do with it
to be able to use it to try to reproduce the problems I'm having. I guess that
somehow I have to get the nightly build working and that's what I don't know how
to do. Do I just click on the file, or is there a command I have to use? I'm
guessing I may have to unzip it first.
I'd like to try to get it working and get the results of using it to you
before I leave on Sunday Morning, so you have something to work with.
I'm also not quite sure what is involved in capturing the performance
profile. Can you give me some instructions on that. And what do I do with
"https://perf-html.io/", and finally, what do you mean when you say "add-on".
Sorry to be so ignorant.
Please get back to me asap, so I can try to get this done before I go away.

                                            Best regards,
                                            Jess Weil

(In reply to Clara Guerrero from comment #1)

Hi!
Can you attach your about:support information please?
It would help us if you can provide a memory report from about:memory, here are the steps for you to get it:

In the URL bar type about:memory and press enter
Click ""Measure and save"" (optionally with ""anonymize"" checked to hide URLs, although this will likely make it more difficult for us to figure out which site, if any, is causing the leak)
Save the memory report somewhere
Attach the report to this bug

Also it would help us a lot if you could reproduce this issue on our latest Nightly build, it can be downloaded from here: https://nightly.mozilla.org/
Then capture a performance profile using
https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Profiling_with_the_Built-in_Profiler
https://perf-html.io/
Please also note that this add-on works only on FF Nightly, so that means you need to be able to reproduce the issue on Nightly first.

Best,
Clara

Comment 3

[Jess Weil]

Attachment: memory-report.json.gz

Comment 4

[Jess Weil]

When I checked if the about:memory report had attached yesterday, I found that it had not, so I tried again now. I clicked Submit at the end, and I think it is now attached. So get back to me ASAP on how to do the other tasks, and I'll try to do them before I leave.

(In reply to Clara Guerrero from comment #1)

Hi!
Can you attach your about:support information please?
It would help us if you can provide a memory report from about:memory, here are the steps for you to get it:

In the URL bar type about:memory and press enter
Click ""Measure and save"" (optionally with ""anonymize"" checked to hide URLs, although this will likely make it more difficult for us to figure out which site, if any, is causing the leak)
Save the memory report somewhere
Attach the report to this bug

Also it would help us a lot if you could reproduce this issue on our latest Nightly build, it can be downloaded from here: https://nightly.mozilla.org/
Then capture a performance profile using
https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Profiling_with_the_Built-in_Profiler
https://perf-html.io/
Please also note that this add-on works only on FF Nightly, so that means you need to be able to reproduce the issue on Nightly first.

Best,
Clara

Comment 5

[Julien Wajsberg [:julienw]]

Hey Jess,

We were looking at this bug today, but we're missing some information to be able to debug that.

First of all: does that still happen?
If yes, can you give us some examples of the websites that break for you?

Then about your other questions:

1. To install nightly on Linux, yes you can unzip it anywhere, then run the "firefox" binary that's inside this zip. You may want to update it before moving on with the next steps.
2. Then you can go to profiler.firefox.com, click this "enable profiler menu" button.
3. This will make this button appear in your address bar. You can click on it, then wait a bit, then run your scenario where things break, then click on it again. This should open automatically a new tab.
4. From this new tab, you can upload the "profile" by clicking "upload" at the top right.

Hope this helps, and hopefully we'll be able to debug this problem!
Thanks a lot

Comment 6

[Mike Conley (:mconley) (:⚙️)]

We haven't heard from Jess in 3 months, so closing as INCOMPLETE.

Jess, if you are able to respond to the needinfo in comment 5, we can re-open the bug.