1924100 - 15.03 - 2.03% wikipedia fcp / wikipedia loadtime + 12 more (Linux) regression on Wed October 9 2024

Status: RESOLVED FIXED

(Core :: Widget: Gtk, defect)

Description

[Treeherder Bug Filer]

Perfherder has detected a browsertime performance regression from push 0bf3e92d26d3bd05bd97d6ccd5cd002303876650. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)	Performance Profiles
15%	wikipedia fcp	linux1804-64-shippable-qr	cold fission webrender	973.60 -> 1,119.97	Before/After
13%	wikipedia PerceptualSpeedIndex	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,075.27 -> 1,214.09	Before/After
12%	wikipedia FirstVisualChange	linux1804-64-shippable-qr	cold fission webrender	1,081.83 -> 1,210.53	Before/After
12%	wikipedia largestContentfulPaint	linux1804-64-shippable-qr	cold fission webrender	1,127.70 -> 1,261.34	Before/After
12%	wikipedia ContentfulSpeedIndex	linux1804-64-shippable-qr	cold fission webrender	1,083.03 -> 1,210.83	Before/After
12%	wikipedia PerceptualSpeedIndex	linux1804-64-shippable-qr	cold fission webrender	1,087.60 -> 1,215.24	Before/After
12%	wikipedia SpeedIndex	linux1804-64-shippable-qr	cold fission webrender	1,095.51 -> 1,222.77	Before/After
11%	wikipedia fcp	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,004.87 -> 1,118.11	Before/After
11%	wikipedia largestContentfulPaint	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,145.85 -> 1,266.38	Before/After
10%	wikipedia ContentfulSpeedIndex	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,098.15 -> 1,212.63	Before/After
10%	wikipedia FirstVisualChange	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,097.60 -> 1,212.04	Before/After
10%	wikipedia PerceptualSpeedIndex	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,103.19 -> 1,216.86	Before/After
10%	wikipedia SpeedIndex	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,111.00 -> 1,224.14	Before/After
2%	wikipedia loadtime	linux1804-64-shippable-qr	bytecode-cached cold fission webrender	1,476.21 -> 1,506.14	Before/After

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests. Please follow our guide to handling regression bugs and let us know your plans within 3 business days, or the patch(es) may be backed out in accordance with our regression policy.

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a sheriff to do that for you.

You can run all of these tests on try with ./mach try perf --alert 2422

The following documentation link provides more information about this command.

For more information on performance sheriffing please see our FAQ.

If you have any questions, please do not hesitate to reach out to [e-mail].

Comment 1

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 1922872

Comment 2

[Emilio Cobos Álvarez [:emilio]]

I don't really see how this can happen, but let's try nerfing the patch to confirm....

Accent-color:

• https://perf.compare/compare-results?baseRev=b24fc2115024e4ab59fd755ffb20f454cfbea56e&newRev=a3fa8711abfd652dec9f4dca0b524ddf94996fc8&baseRepo=try&newRepo=try&framework=13

Contrast:

• https://perf.compare/compare-results?baseRev=b24fc2115024e4ab59fd755ffb20f454cfbea56e&newRev=e7d4b16c894a3a7226ce07126ca47ffdacb698e4&baseRepo=try&newRepo=try&framework=13

Comment 3

[Emilio Cobos Álvarez [:emilio]]

Hmm, how likely is this to be correct?

• My patch doesn't have anything particularly independent to wikipedia.
• The relevant code doesn't show up in either profiles.
• Automation doesn't even use Adwaita (it uses Yaru because it's ubuntu).
• Nerfing it (comment 2) doesn't show confident results one way or the other.

Trying with a full backout just in case:

• https://perf.compare/compare-results?baseRev=adba913f732f7261f835c23c5a68c20a382db4fb&newRev=f3d029f4a18c6e1a48a99da5d5149bda515577fe&baseRepo=try&newRepo=try&framework=13

Comment 4

[Andra Esanu (needinfo me)]

The graphs indicate to have a culprit for this push.
:sparky Could you please help with providing more context for this?

Comment 5

[Emilio Cobos Álvarez [:emilio]]

Yeah I guess the full backout indicates some high confidence improvements. I'm still confused as to how but ok, let me dig more...

Comment 6

[Emilio Cobos Álvarez [:emilio]]

Trying to see if it's a hunch of mine: https://perf.compare/compare-results?baseRev=cbe29dff022e6e807f3a4df7c7af2df9729e9ad2&newRev=cccf7a63d228b572dbe187df35fc23d09ccc06f5&baseRepo=try&newRepo=try&framework=13

Comment 7

[Donal Meehan [:dmeehan]]

:emilio Fx133 goes to beta on Monday 2024-10-28. Do you plan on adding a patch before then?

Comment 8

[Emilio Cobos Álvarez [:emilio]]

Yes, or we should back out from beta. I am actively investigating this now.

Comment 9

[Emilio Cobos Álvarez [:emilio]]

https://perf.compare/compare-results?baseRev=9e1d15d88b9abbab091110af69dd6d32d8053e09&newRev=c763169ea83c31019f32b27e3f70a62aaf271a5e&baseRepo=try&newRepo=try&framework=13

Comment 10

[Donal Meehan [:dmeehan]]

(In reply to Emilio Cobos Álvarez (:emilio) from comment #8)

Yes, or we should back out from beta. I am actively investigating this now.

Thanks, I'll back out from beta if you don't land a patch before then

Comment 11

[Emilio Cobos Álvarez [:emilio]]

https://perf.compare/compare-results?baseRev=9e1d15d88b9abbab091110af69dd6d32d8053e09&newRev=699495728e15e3992d0f2d935eeec72b2ccc9083&baseRepo=try&newRepo=try&framework=13

Comment 12

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1924100 - More fine-grained settings change. r=stransky

Avoid calling OnSettingsChange when we start watching dbus if nothing
changed.

OnSettingsChanged already checks sIgnoreChangedSettings.

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/703fb617c8b7
More fine-grained settings change. r=stransky

Comment 14

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/703fb617c8b7

Comment 15

[Andrej (:aglavic)]

We've seen the changes on our side, thanks for all the work! :)

Perfherder has detected a talos performance change from push 703fb617c8b70339e2c95cc43de4b8116d867f3e.

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
29%	ts_paint_webext	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	692.92 -> 494.33
28%	ts_paint	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	691.50 -> 495.25
23%	ts_paint	linux1804-64-shippable-qr	e10s fission stylo webrender	837.08 -> 647.00
22%	ts_paint	linux1804-64-shippable-qr	e10s fission stylo webrender	833.25 -> 647.00
22%	ts_paint_webext	linux1804-64-shippable-qr	e10s fission stylo webrender	831.75 -> 646.67
...	...	...	...	...
14%	startup_about_home_paint	linux1804-64-shippable-qr	e10s fission stylo webrender	1,272.00 -> 1,098.08

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests.

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a sheriff to do that for you.

You can run these tests on try with ./mach try perf --alert 42377

For more information on performance sheriffing please see our FAQ.