Bug 217114

Summary:	REGRESSION: [ iOS release wk2 ] compositing/debug-borders-dynamic.html is a flaky image failure
Product:	WebKit	Reporter:	Karl Rackler <rackler>
Component:	Compositing	Assignee:	Karl Rackler <rackler>
Status:	RESOLVED FIXED
Severity:	Normal	CC:	Morningstar, simon.fraser, webkit-bot-watchers-bugzilla, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description Karl Rackler 2020-09-29 18:24:42 PDT

Description:
compositing/debug-borders-dynamic.html

The first image failure that I see this on the dashboard was 09/29/20 at r267758, but does not appear to be relevant to what would have caused this.
There is only one day of test history with this being the only image failure on the dashboard so far.

The test was expecting to repaint 2px solid red border with transform, but seems to have returned without transform.

History:
https://results.webkit.org/?suite=layout-tests&test=compositing%2Fdebug-borders-dynamic.html&limit=50000&version_name=iOS%2014

Diff:
https://build.webkit.org/results/Apple-iOS-14-Simulator-Release-WK2-Tests/r267758%20(20)/compositing/debug-borders-dynamic-diffs.html

Comment 1 Radar WebKit Bug Importer 2020-09-29 18:25:27 PDT

<rdar://problem/69772621>

Comment 2 Karl Rackler 2020-09-29 18:38:59 PDT

I have marked this test as image failure while this issue is investigated.
https://trac.webkit.org/changeset/267776/webkit

Comment 3 Karl Rackler 2020-09-30 17:08:43 PDT

REPRODUCTION STEPS
Build 17H35:
I can reproduce this image failure with most recent available spade r267194.

Build 18A393:
I can reproduce this image failure on all spades tried between r262500 and ToT 267802.  The test will usually fail within the first 50 to 100 iterations.  Because the test was consistent in failures, I cannot pinpoint a change that could have caused this.

Command: 
run-webkit-tests --ios-simulator --iterations 2000 --exit-after-n-failures 1 --exit-after-n-crashes-or-timeouts 1 --debug-rwt-logging --no-retry --force --no-build -f compositing/debug-borders-dynamic.html

Result: 
Regressions: Unexpected image-only failures (1)
  compositing/debug-borders-dynamic.html [ ImageOnlyFailure ]

Comment 4 Dawn Morningstar 2022-03-07 15:52:19 PST

compositing/debug-borders-dynamic.html 
Is still a flaky failure on iOS Debug queue, as an expectation has not been set.

Comment 5 Simon Fraser (smfr) 2022-03-15 10:39:51 PDT

This should be solved with pixel tolerance (it's some pixel fuzz around the repaint counter).

Comment 6 Karl Rackler 2023-06-20 18:09:33 PDT

Pull request: https://github.com/WebKit/WebKit/pull/15124

Comment 7 Karl Rackler 2023-06-20 18:10:19 PDT

Adjusting pixel tolerance for the following test:
compositing/debug-borders-dynamic.html

Comment 8 EWS 2023-06-20 19:19:50 PDT

Committed 265343@main (98fc2d9d56ca): <https://commits.webkit.org/265343@main>

Reviewed commits have been landed. Closing PR #15124 and removing active labels.

Comment 9 Karl Rackler 2023-06-21 08:29:35 PDT

Adjusting pixel tolerance for the following test:
compositing/debug-borders-dynamic.html

Comment 10 Karl Rackler 2023-06-21 08:37:04 PDT

Re-opening for pull request https://github.com/WebKit/WebKit/pull/15145

Comment 11 EWS 2023-06-21 08:41:12 PDT

Committed 265360@main (5512c619b8aa): <https://commits.webkit.org/265360@main>

Reviewed commits have been landed. Closing PR #15145 and removing active labels.

Comment 12 Karl Rackler 2023-06-21 12:32:25 PDT

Remove test expectations

Comment 13 EWS 2023-06-21 12:36:02 PDT

Test gardening commit 265368@main (e6e95e294e70): <https://commits.webkit.org/265368@main>

Reviewed commits have been landed. Closing PR #15154 and removing active labels.