1380331 - [e10s a11y] Letting the machine go into hibernation and waking it up results in performance degradation in focus events, switching tabs etc.

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect, P2)

Description

[Marco Zehe (:MarcoZ)]

Rough STR:
1. Start NVDA and Firefox in E10S mode on a Windows 10 Creators Update machine. The actual edition might not matter, it's just what I have.
2. Use it for a while. Notice that focus changes, tab switching etc. are all quite snappy if the load doesn't get too heavy on the browser (like on Facebook or Twitter).
3. Pause your activity, leaving the current tab open. Let your machine go to screen lock/hibernation or whatever it does after a few minutes of not using it. My system turns off the screen and falls into a slumber.
4. After a few minutes, wake it up again, and log back in.
5. Continue using Firefox and NVDA together.

Result: On first try, the slow-down is subtle. If I repeat steps 2 through 5 twice or three times more, the slow-down in focus changes, tab switching, document loading etc. becomes really pronounced.

This is not a new problem, it's been there for longer I presume, but I am now noticing it since I am using E10S all the time during my daily usage. After 4 or 5 slumbers, Firefox becomes almost unusable for me, and I have to shut it down and restart. After I do that, things return to normal, until the next slumber.

Comment 1

[u554753]

Putting needinfo on myself to look at this during Pre-Beta testing.

Comment 2

[David Bolter [:davidb] (NeedInfo me for attention)]

standup meeting update: we're not going to block on this per MarcoZ.

Comment 3

[u554753]

Reproducible. Restarting Firefox usually fixes this issue.

Comment 4

[James Teh [:Jamie]]

Marco, can you still reproduce this?

Comment 5

[Marco Zehe (:MarcoZ)]

Yes. At least on one machine, running Windows 10 19H1, after waking up from hibernation, Firefox and NVDA become very slow. I have to shut down Firefox and restart it to get it back to a normal working state. It is kind of similar now to the behavior we sometimes observe when Firefox slows down to a crawl after working for several hours. So in that sense, the problem has become even more reproducible for me, but only on my Surface Laptop 2. The Dell which I use for work doesn't exhibit this problem. Don't know why.

Comment 6

[Negritas Sergiu, Desktop QA]

Hello! I have tried to reproduce the issue on Windows 10 and NVDA with firefox 96.0a1(2021-11-15), 95.0b7 and 94.0.1. Adding the QA-not-reproducible flag since we could not reproduce the issue.

Marco is this issue still valid or we can close it as WFM?

Thank you!

Comment 7

[James Teh [:Jamie]]

I suspect this is a different manifestation of bug 1572915 with the same underlying symptoms and cause. We're still getting user reports of this, even though it's somewhat intermittent and not easy to reproduce on demand.

Comment 8

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

In the process of migrating remaining bugs to the new severity system, the severity for this bug cannot be automatically determined. Please retriage this bug using the new severity system.

Comment 9

[James Teh [:Jamie]]

This is resolved by Cache the World, which is enabled by default in Firefox 113.