1905863 - 9.11 - 7.85% cpstartup content-process-startup / cpstartup content-process-startup + 1 more (Windows) regression on Fri June 14 2024

Status: RESOLVED FIXED

(Core :: Security: Process Sandboxing, defect)

Description

[Acasandrei Beatrice (needinfo me)]

Perfherder has detected a talos performance regression from push 5d8fe1ab20de59caa9861b8f2984ad136f32cb92. 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)
9%	cpstartup content-process-startup	windows10-64-shippable-qr	e10s fission stylo webrender	63.08 -> 68.83
9%	cpstartup content-process-startup	windows10-64-shippable-qr	e10s fission stylo webrender-sw	62.83 -> 68.50
8%	cpstartup content-process-startup	windows10-64-shippable-qr	e10s fission stylo webrender	63.12 -> 68.08

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 these tests on try with ./mach try perf --alert 904

For more information on performance sheriffing please see our FAQ.

Comment 1

[Acasandrei Beatrice (needinfo me)]

I linked all the bugs that could have caused this performance regression since it's difficult for me to tell which one is the culprit. Please update the Regressed by field accordingly. Thank you!

Comment 2

[Bob Owen (:bobowen)]

I think that this has already been fixed by bug 1903523.
I think that bug 1903523 was the cause of the reversing alert: https://treeherder.mozilla.org/perfherder/alerts?id=985

Comment 3

[Acasandrei Beatrice (needinfo me)]

Based on the graphs you are correct and I think we can close this since there is no action item needed.

Comment 4

[Bob Owen (:bobowen)]

Fixed by patch in bug 1903523.

Comment 5

[Bob Owen (:bobowen)]

I think bug 1901554 was the main regressor here.
Looking into allowing those DLLs to load later, without preloading.