1810275 - On a JS demo (http://nkunited.de/blog/particles/landscape/SinusLandscape.min.html) Nightly is slower than Chrome (in certain cases)

Status: NEW

(Core :: JavaScript Engine, task, P3)

Description

[Mayank Bansal]

1. Go to http://nkunited.de/blog/particles/landscape/SinusLandscape.min.html

2. Click on "Open Controls" -> General Settings
   2.1Increase the "Particle Amount" to maximum

3.Click on Open Controls -> Display settings
Check "Z-sorting"

AR: Nightly is much more slower than Chrome.

Nightly: https://share.firefox.dev/3kf5tps
Chrome: https://share.firefox.dev/3CPhQyZ

Comment 1

[Jan de Mooij [:jandem]]

Are you sure that Chrome trace was with Z-sorting enabled? In your Nightly profile I see a lot of time is spent sorting an array but I don't see that in your Chrome profile at all. Looking at the code, this sorting only happens if Z-sorting is enabled.

Comment 2

[Mayank Bansal]

(In reply to Jan de Mooij [:jandem] from comment #1)

Are you sure that Chrome trace was with Z-sorting enabled? In your Nightly profile I see a lot of time is spent sorting an array but I don't see that in your Chrome profile at all. Looking at the code, this sorting only happens if Z-sorting is enabled.

https://share.firefox.dev/3QGREfN
The first 5 seconds are without z-sorting. After that, I enabled z-sorting.

Comment 3

[Jan de Mooij [:jandem]]

(In reply to Mayank Bansal from comment #2)

https://share.firefox.dev/3QGREfN
The first 5 seconds are without z-sorting. After that, I enabled z-sorting.

Ah yes, now the sort callback shows up, as "(anonymous)". I suspect this is mostly a sorting thing.

Comment 4

[Mayank Bansal]

Profile with latest Nightly(that contains fixes from bug 1884360) : https://share.firefox.dev/3TXVLYc

Comment 5

[Mayank Bansal]

This is what I get on the latest Nightly (which contains fix from bug 1889685 : https://share.firefox.dev/3WoXNlx

Comment 6

[Jan de Mooij [:jandem]]

How does performance compare to Chrome now? Eyeballing the profile, we spend a lot less (relative) time sorting now.

Comment 7

[Mayank Bansal]

Subjectively, Nightly feels slower.

Nightly: https://share.firefox.dev/3JFZZ0o
Chrome: https://share.firefox.dev/3Wm0HaB

Comment 8

[Mayank Bansal]

Attachment: bandicam 2024-04-30 13-15-53-451.mp4

Comment 9

[Jan de Mooij [:jandem]]

One remaining difference is the number of comparator calls: in Nightly that's about 1.2-1.3 million calls per sort call (it varies quite a bit), but with Chrome it's 0.9-0.95 million. So we're doing more work.. V8 uses Timsort so this could be bug 720677, or something else.

Safari has fewer comparator calls than us, but they're pretty similar (they're closer to us than to Chrome).

Comment 10

[Mayank Bansal]

Profile with fix from bug 1893977: https://share.firefox.dev/3JKuRwJ