Bug 181957 – Layout Test http/tests/misc/resource-timing-resolution.html is a flaky failure

• Component: New Bugs
• Status: RESOLVED FIXED

[Ryan Haddad]

The following layout test is flaky on release testers

http/tests/misc/resource-timing-resolution.html

Probable cause:

Unknown.

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=http%2Ftests%2Fmisc%2Fresource-timing-resolution.html

--- /Volumes/Data/slave/highsierra-release-tests-wk1/build/layout-test-results/http/tests/misc/resource-timing-resolution-expected.txt
+++ /Volumes/Data/slave/highsierra-release-tests-wk1/build/layout-test-results/http/tests/misc/resource-timing-resolution-actual.txt
@@ -3,7 +3,7 @@
 On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
 
 
-PASS t0 !== t1 is true
+FAIL t0 !== t1 should be true. Was false.
 PASS shouldBeNearZeroOrOne < 1e-10 || Math.abs(shouldBeNearZeroOrOne - 1) < 1e-10 is true
 PASS successfullyParsed is true

[Ryan Haddad]

The earliest failure visible on the dashboard is https://trac.webkit.org/changeset/226646/webkit, but that change is unrelated.

[Matt Lewis]

Marked as flaky https://trac.webkit.org/changeset/227451/webkit

[Ryan Haddad]

This test has become very flaky after https://trac.webkit.org/changeset/238877/webkit

The diff is the same as the one above.

https://build.webkit.org/results/Apple%20Mojave%20Release%20WK1%20(Tests)/r238912%20(1467)/results.html

[Jiewen Tan]

(In reply to Ryan Haddad from comment #3)
> This test has become very flaky after
> https://trac.webkit.org/changeset/238877/webkit
> 
> The diff is the same as the one above.
> 
> https://build.webkit.org/results/Apple%20Mojave%20Release%20WK1%20(Tests)/
> r238912%20(1467)/results.html

I don’t think so. I tried to ran the test 1000 times before and after my change. It more or less reserves the same level of flakiness. Also, I don’t think there is anything my patch could affect this test case as it doesn’t have any iframes.

[Ryan Haddad]

(In reply to Jiewen Tan from comment #4)
> (In reply to Ryan Haddad from comment #3)
> > This test has become very flaky after
> > https://trac.webkit.org/changeset/238877/webkit
> > 
> > The diff is the same as the one above.
> > 
> > https://build.webkit.org/results/Apple%20Mojave%20Release%20WK1%20(Tests)/
> > r238912%20(1467)/results.html
> 
> I don’t think so. I tried to ran the test 1000 times before and after my
> change. It more or less reserves the same level of flakiness. Also, I don’t
> think there is anything my patch could affect this test case as it doesn’t
> have any iframes.

Hm, the flakiness dashboard shows a drastic increase in the number of failures starting yesterday. Even if it isn't your revision, something definitely changed.

[Jiewen Tan]

(In reply to Ryan Haddad from comment #5)
> (In reply to Jiewen Tan from comment #4)
> > (In reply to Ryan Haddad from comment #3)
> > > This test has become very flaky after
> > > https://trac.webkit.org/changeset/238877/webkit
> > > 
> > > The diff is the same as the one above.
> > > 
> > > https://build.webkit.org/results/Apple%20Mojave%20Release%20WK1%20(Tests)/
> > > r238912%20(1467)/results.html
> > 
> > I don’t think so. I tried to ran the test 1000 times before and after my
> > change. It more or less reserves the same level of flakiness. Also, I don’t
> > think there is anything my patch could affect this test case as it doesn’t
> > have any iframes.
> 
> Hm, the flakiness dashboard shows a drastic increase in the number of
> failures starting yesterday. Even if it isn't your revision, something
> definitely changed.

How about I fix the thing and relieve us all.

[Jiewen Tan]

Created attachment 356689 [details]
Patch

[Ryan Haddad]

(In reply to Jiewen Tan from comment #6)
> How about I fix the thing and relieve us all.

Works for me. Thanks, Jiewen!

[Jiewen Tan]

Comment on attachment 356689 [details]
Patch

Thanks Youenn for r+ it.

[WebKit Commit Bot]

Comment on attachment 356689 [details]
Patch

Clearing flags on attachment: 356689

Committed r238935: <https://trac.webkit.org/changeset/238935>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/46529944>