several performance issues with muon based on C69

[kjozwiak]

Test plan

1. Launch Brave on macOS
2. Resize the window a bunch. Try to do it fast and ensure that behavior matches our existing live version (0.23.107)
3. Try loading a lot of tabs and bookmarks (as @LaurenWags describes in several performance issues with muon based on C69 #15202 (comment)) and quit / relaunch. Performance should match 0.23.107

Description

There seems to be a few performance issues with muon that includes C69. So far we've noticed the following area's that seem a bit slower/jankier compared to the current 0.23.107 6f2fc65 build which is based on 68.0.3440.84:

• window resizing
• application launch time
• detaching tabs from a window

Steps to Reproduce

1. install 0.23.107 6f2fc65 and resize the window several times (note the performance)
2. install 0.23.206 80a5ac1 and resize the window several times (note the performance)

You'll notice a big difference in performance between 0.23.107 and 0.23.206 when it comes to resizing windows.

Actual result:

Resizing windows on 0.23.206 80a5ac1 is a lot slower/jankier compared to 0.23.107 6f2fc65 which feels a lot more snappier. Definitely seems like the performance has decreased with 0.23.206 80a5ac1.

Expected result:

Resizing windows on 0.23.206 80a5ac1 should be as performant as 0.23.107 6f2fc65.

Reproduces how often:

100% reproducible using the above STR.

Brave Version

about:brave info:

Brave: 0.23.206 
V8: 6.9.427.22 
rev: 80a5ac134e251a9cb3565023e2447d6d7b4487a7 
Muon: 8.1.5 
OS Release: 17.7.0 
Update Channel: Release 
OS Architecture: x64 
OS Platform: macOS 
Node.js: 7.9.0 
Brave Sync: v1.4.2 
libchromiumcontent: 69.0.3497.92

Reproducible on current live release:

No, not reproducible under 0.23.107 6f2fc65 which is currently the released version based on C68.

Additional Information

[LaurenWags]

Using macOS, I did some comparisons of 0.23.107 to 0.23.206 in the following areas:

1. tab resizing - verified resizing a window isn’t as smooth on 0.23.206
2. launch - tried two ways first way was with a profile with 1 window, 7 tabs. in both versions Brave took about 3 to 3.5 seconds to launch. second way tried was a profile with 4 windows, each window has 150 tabs. with 0.23.107 Brave launched in about 9.5-10s, and in 0.23.206 Brave launched in about 10-10.5s. slightly slower on 0.23.206 but not absurdly so.
3. tab detach - I’m not noticing much of a difference between the two versions in this area. 0.23.206 might be a tiny bit slower, but it’s not obvious on my machine.

[kjozwiak]

@bsclifton I went through all the C69 that were uploaded. Hopefully this helps you narrow down the issue but it seems like it's been in C69 since the start:

• 0.23.206 80a5ac1 - reproduced resizing issue (CR: 69.0.3497.92)
• 0.23.205 81396b3 - reproduced resizing issue (CR: 69.0.3497.92)
• 0.23.204 b71d170 - reproduced resizing issue (CR: 69.0.3497.81)
• 0.23.203 16c2c19 - reproduced resizing issue (CR: 69.0.3497.72)
• 0.23.202 bfbd176 - reproduced resizing issue (CR: 69.0.3497.72)
• 0.23.201 17d2d17 - reproduced resizing issue (CR: 69.0.3497.57)

[srirambv]

App response on Windows is pretty fast same as previous versions. The new tab image load time is slow. On Linux, resizing tab is a little choppy but the new tab image load is pretty instant.

[bsclifton]

Fixed with brave/muon@6c2f235

[bridiver]

also https://github.com/brave/browser-laptop-bootstrap/commit/657c7178e81bb30ddfb687800161b4dcc9caf3e1

[LaurenWags]

Verified with macOS 10.12.6 using

• 0.23.207 281de88
• Muon 8.1.6
• libchromiumcontent 69.0.3497.100

1. tab resizing - verified resizing is much smoother with 0.23.207 and works like 0.23.107
2. launch - verified with a profile with 4 windows, each window has 150 tabs, version 0.23.207 of Brave launched in about 10-10.5s.
3. tab detach - verified tab detach appears to be the same on 0.23.107 and 0.23.207 and there is not a noticeable difference.

[kjozwiak]

With a clean profile using 0.23.207, ensured that the following cases felt fast and didn't have any noticeable performance regressions:

• resizing multiple windows
• moving the windows around the screen
• opening tabs (normal, PT, Tor PT & session)
• detaching/re-attaching tabs
• restarting after about:preferences changes
• restoring sessions

I also went through the above cases using a large profile that has 3 windows and ~150 tabs.

Verified on macOS 10.13.6 using the following build:

• 0.23.207 281de88
• muon: 8.1.6
• libchromiumcontent: 69.0.3497.100