Closed Bug 1832332 Opened 2 years ago Closed 2 years ago

3.01 - 2.83% nytimes PerceptualSpeedIndex / nytimes PerceptualSpeedIndex (Windows) regression on Wed May 3 2023

Categories

(Core :: JavaScript Engine, defect)

Product:
Core
Component:
JavaScript Engine
Type:
defect

Tracking

()

Status:
RESOLVED WONTFIX
Tracking Flags:
Tracking Status
firefox-esr102 --- unaffected
firefox113 --- unaffected
firefox114 --- wontfix
firefox115 --- wontfix

People

(Reporter: aesanu, Unassigned)

References

(Regression)

Details

(Keywords: perf, perf-alert, regression)

Perfherder has detected a browsertime performance regression from push 803bd3263cb90b8c89446934393eab7ef50852b8. 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)
3% nytimes PerceptualSpeedIndex windows10-64-shippable-qr fission warm webrender 411.29 -> 423.67
3% nytimes PerceptualSpeedIndex windows10-64-shippable-qr fission warm webrender 410.12 -> 421.75

Improvements:

Ratio Test Platform Options Absolute values (old vs new)
5% nytimes loadtime windows10-64-shippable-qr cold fission webrender 1,518.66 -> 1,444.17

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 offending 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.

For more information on performance sheriffing please see our FAQ.

Flags: needinfo?(jdemooij)

Set release status flags based on info from the regressing bug 1830727

status-firefox113: --- → unaffected
status-firefox114: --- → affected
status-firefox-esr102: --- → unaffected

This might be caused by differences in bytecode size: many self-hosted functions should have shorter bytecode now, which could affect our inlining decisions among other things. Bug 1830727 should be a clear improvement, because fewer bytecode ops, fewer branches and fewer Baseline ICs.

It's also curious that "nytimes loadtime cold" improved by 5% and "nytimes PerceptualSpeedIndex warm" regressed by 3%.

I'm leaning to WONTFIX based on this.

I'm closing this, see comment 2.

Status: NEW → RESOLVED
Closed: 2 years ago
Flags: needinfo?(jdemooij)
Resolution: --- → WONTFIX
You need to log in before you can comment on or make changes to this bug.