Bug 259658

Summary:	REGRESSION (257403@main?): [ macOS ] http/tests/media/video-play-stall.html is a flaky failure
Product:	WebKit	Reporter:	Ben Schwartz <ben_schwartz>
Component:	Media	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	graouts, jean-yves.avenard, rackler, webkit-bot-watchers-bugzilla, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description Ben Schwartz 2023-07-31 12:57:25 PDT

http/tests/media/video-play-stall.html

This test has been a flaky failure on all platforms as far as the flakiness dashboard extends.

TEXT DIFF:

 EVENT(loadedmetadata)
 EVENT(loadeddata)
 EVENT(stalled)
-TEST(video.currentTime <= bufferedend) OK
+TEST(video.currentTime <= bufferedend) FAIL
 TEST(gotCanplay ? video.paused == false : video.paused == true) OK
 EXPECTED (video.playbackRate === '1') OK
 TEST(video.duration > bufferedend) OK

DIFF URL:

https://build.webkit.org/results/Apple-Ventura-Debug-AppleSilicon-WK2-Tests/266142@main%20(3111)/http/tests/media/video-play-stall-pretty-diff.html

Comment 1 Radar WebKit Bug Importer 2023-07-31 12:57:34 PDT

<rdar://problem/113157201>

Comment 2 Ben Schwartz 2023-07-31 14:42:38 PDT

I have marked this test as a flaky failure while this issue is investigated. (Link: https://github.com/WebKit/WebKit/pull/16240)

Comment 3 Ben Schwartz 2023-07-31 16:03:50 PDT

History link: https://results.webkit.org/?suite=layout-tests&test=http%2Ftests%2Fmedia%2Fvideo-play-stall.html

Comment 4 Ben Schwartz 2023-07-31 22:25:43 PDT

I was unable to reproduce this bug on macOS Ventura arm64; however, I suspect this may be due to how videos are loaded and buffered in certain environments (given that the error is because the video's current time is greater than the buffered time). Either way, more investigation is needed to be sure.

Comment 5 Karl Rackler 2023-08-01 07:15:21 PDT

This issue can be reproduced using command:
run-webkit-tests --release -f --clobber-old-results --exit-after-n-failures 1 --force  --child-processes=5 --iterations=100 http/tests/media/video-play-stall.html

Comment 6 EWS 2023-08-01 07:20:33 PDT

Test gardening commit 266474@main (c22c66c0cc2e): <https://commits.webkit.org/266474@main>

Reviewed commits have been landed. Closing PR #16240 and removing active labels.

Comment 7 Ryan Haddad 2023-10-20 15:23:45 PDT

It looks like https://commits.webkit.org/257403@main is when the test became flaky