1186479 - Regression - OSX - Slow performance when hovering over the Window Control Buttons

Status: RESOLVED WORKSFORME

(Core :: Widget: Cocoa, defect)

Description

[Mehmet]

Attachment: Window control buttons.mov

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:42.0) Gecko/20100101 Firefox/42.0
Build ID: 20150722030205

Steps to reproduce:

1.) Hover over the Window Control Buttons in the left upper corner.



Actual results:

The red (x) yellow(-) green(+) should appear immediately.


Expected results:

They appear very slow.

A screencast is attached.

Comment 1

[Steven Michaud [:smichaud] (Retired)]

I see this too, intermittently (testing with today's m-c nightly on OS X 10.10.4).  It's much more likely to happen on some pages than others.  Here are two examples:

https://www.mozilla.org/en-US/firefox/nightly/firstrun/
https://vimeo.com/channels/staffpicks/132439890

I don't see the bug (or see a much less severe version) with these pages:

Nightly Start Page
Preferences Page
https://bugzilla.mozilla.org/show_bug.cgi?id=1186479

The symptoms seem the same whether e10s is on or off.

Comment 2

[Steven Michaud [:smichaud] (Retired)]

Regression range:

firefox-2015-07-07-03-02-06-mozilla-central
firefox-2015-07-08-03-02-04-mozilla-central
http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=e7e69cc8c07b&tochange=9b902b7669ae

Comment 3

[Steven Michaud [:smichaud] (Retired)]

I can't figure out just by looking which patch in the regression range is the trigger for this bug.  Though I'd guess it's probably one of the many patches for bug 1143575.

Comment 4

[Steven Michaud [:smichaud] (Retired)]

I also see this bug on OS X 10.7.5.  So it's presumably not OS-X-version-specific.

Comment 5

[Steven Michaud [:smichaud] (Retired)]

I see the bug with or without HiDPI mode.

Comment 6

[Wayne Mery (:wsmwk)]

> I'd guess it's probably one of the many patches for bug 1143575.

still the best culprit?

Comment 7

[Steven Michaud [:smichaud] (Retired)]

> still the best culprit?

I haven't looked at this (or thought about it) since my original comment.  So I'd have to say "yes".

Comment 8

[Tracy Walker [:tracy]]

This is WFM on 10.11, with latest Nightly 49.0a1, 20160518030234