1761967 - High memory usage (>1GB) in layout / display-list-arena for the browser window

Status: RESOLVED DUPLICATE of bug 1760847

(Core :: Web Painting, defect, P2)

Description

[Henrik Skupin [:whimboo][⌚️UTC+2]]

I have a huge block of memory being used by display-list-arena that is marked with LISTNODE. Here the details from a verbose memory measurement from about:memory:

2,336,908,383 B (100.0%) -- explicit
├──1,455,169,872 B (62.27%) -- window-objects
│  ├──1,313,206,864 B (56.19%) -- top(chrome://browser/content/browser.xhtml, id=3)/active
│  │  ├──1,310,619,400 B (56.08%) -- window(chrome://browser/content/browser.xhtml)
│  │  │  ├──1,301,971,608 B (55.71%) -- layout
│  │  │  │  ├──1,291,769,344 B (55.28%) -- display-list-arena
│  │  │  │  │  ├──1,291,041,824 B (55.25%) ── LISTNODE

Comment 1

[Miko Mynttinen]

Yikes, that is not good.

Comment 2

[Miko Mynttinen]

Henrik, what did you do before checking the memory measurements and is this on Nightly?

Comment 3

[Henrik Skupin [:whimboo][⌚️UTC+2]]

It was on Nightly, yes. The process was running for quite some time (more than a week) and as such I did a lot but also put the machine asleep (hibernation) a lot. Maybe this could be related?

Comment 4

[Miko Mynttinen]

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+1] from comment #3)

It was on Nightly, yes. The process was running for quite some time (more than a week) and as such I did a lot but also put the machine asleep (hibernation) a lot. Maybe this could be related?

Do you think it's possible that this was without the patch for bug 1760847, meaning Nightly older than 2022-03-23?

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Oh yes, definitely. I had 20220320213921 installed before. Sorry that I missed the version info in my initial comment. So it means that this is already fixed?

Comment 7

[Miko Mynttinen]

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+1] from comment #6)

Oh yes, definitely. I had 20220320213921 installed before. Sorry that I missed the version info in my initial comment. So it means that this is already fixed?

Yes, I believe so.

To be safe, I also went through this code again and added assertions to check that
1) list node allocations and deallocations are balanced inside nsDisplayList.
2) arena allocator has every allocated memory chunk in its freelist when expected.

Neither of these assertions were triggered in any of our tests on try. I'll keep this bug open for a while to see if we get reports with a newer Nightly version.

Comment 8

[Miko Mynttinen]

Because all the reports have so far been for older Nightly, I'll close this as duplicate. If anyone experiences the same issue with Nightly newer than 2022-03-23, please reopen.