1654980 - Extreme performance degradation in Firefox 78.0

Status: RESOLVED WORKSFORME

(Core :: Performance, defect, P3)

Description

[Jens Reimann]

User Agent: Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0

Steps to reproduce:

Upgrade to Firefox 78.0.2

Actual results:

I experience extreme performance degradation. Everything becomes supper laggy. Typing text, loading pages, … and this is only inside the Firefox web browser. The rest of the system is just fine.

I also don't see any spikes in CPU usages from Firefox.

I created a performance profile, but have no idea how to read it: https://share.firefox.dev/2CyOKYX

Expected results:

No performance degradation.

Comment 1

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

Compositor is busy doing something but the profile is rather restricted, so it is hard to see what.

Jens, could you see if you can reproduce using Nightly (https://nightly.mozilla.org/) and share another profile?
And could you perhaps share yet another 78 profile - looking at couple different profile might reveal where the issue could be.
It would be nice to see also the urls, but I understand if you don't want to share that kind of information.

Comment 2

[Daniel Holbert [:dholbert]]

(In reply to Olli Pettay [:smaug] from comment #1)

And could you perhaps share yet another 78 profile - looking at couple different profile might reveal where the issue could be.
It would be nice to see also the urls, but I understand if you don't want to share that kind of information.

Reporter, just following up -- would you mind capturing a new profile? Also, is Firefox 79 (released this week) affected?

Comment 3

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

(Still waiting for reply to the needinfo.)

Comment 4

[Bas Schouten (:bas.schouten)]

With no answer from the reporter, we don’t have enough data to reproduce and/or fix this issue. Please reopen or file a new bug with more information if you see it again.