1772975 - Unrecoverable gmail tab freezes while idle

Status: RESOLVED WORKSFORME

(Core :: Performance: General, defect)

Description

[Katelyn Gadd (:kael)]

Attachment: about:support

I have a gmail tab pinned in my main Firefox window that I check a few times a day. Typically according to about:processes or about:performance, it's using 0-2% of background cpu and a few hundred megs of RAM.

In the last week I've come back twice to find the tab completely frozen and unresponsive - according to about:processes its CPU usage is 110% and the memory usage is bouncing between 400MB and 500MB. None of the normal mechanisms to recover a tab work - refresh, shift-refresh, etc. about:memory no longer works while the tab is hung so I can't capture a memory snapshot of it. There are no messages in the browser console and devtools don't work on the tab. Interacting with the tab doesn't show that little 'tab unresponsive' spinner either, and I can't manually navigate the tab to a new URL. That tab process is just dead.

If I dig the PID out in about:processes and kill it, FF properly spins up a new process for it and reloads it.

I don't see any unsubmitted crashes for these gmail tabs in about:crashes, either, so it seems like the crash reporter isn't catching it.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Performance' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Bas Schouten (:bas.schouten)]

Could you try to grab a profile when this happens? It's possible this may also not work.

I know we've had some issues in the past with events accumulating in background tabs. Olli, do you remember if any of those affected (or may still be affecting) gmail?

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

You're probably thinking the one where promise callbacks were accumulated. That was fixed (like a year+ ago) and I'm not aware of anything else.
And Gmail doesn't use alert() popup, right?

I haven't seen other reports like this.

Comment 4

[Katelyn Gadd (:kael)]

The default profiler in devtools, right? Or a different one? I'm not sure if devtools will successfully open when the tab is in a degraded state, but I'll try.

For what it's worth I haven't seen this in at least a month, so I'd be fine with closing it and then reopening if it comes back. It may be that Google made a change on their end.

Comment 5

[Olli Pettay [:smaug][[e-mail]]]

https://profiler.firefox.com/ is amazing profiler. Especially when one uses it with Nightly and with "Nightly" settings, I think it gives quite a bit information.

But marking this as WFM.