1751733 - High frequency Linux/Windows browser/base/content/test/performance/browser_tabopen.js | unexpected changed rect: ({x1:213, x2:230, y1:4, y2:39, w:18, h:36}), window width: 1280 -

Status: RESOLVED FIXED

(Firefox :: General, defect, P5)

Description

[Treeherder Bug Filer]

Filed by: smolnar [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=365236037&repo=autoland
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/J1fbjOsJTwaztdgAayNBCg/runs/0/artifacts/public/logs/live_backing.log

---

INFO - TEST-PASS | browser/base/content/test/performance/browser_tabopen.js | 0 unexpected reflows - true == true - 
[task 2022-01-24T14:39:13.052Z] 14:39:13     INFO - comparing 4 frames
[task 2022-01-24T14:39:13.053Z] 14:39:13     INFO - Buffered messages finished
[task 2022-01-24T14:39:13.054Z] 14:39:13     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_tabopen.js | unexpected changed rect: ({x1:213, x2:230, y1:4, y2:39, w:18, h:36}), window width: 1280 - 
[task 2022-01-24T14:39:13.054Z] 14:39:13     INFO - Stack trace:
[task 2022-01-24T14:39:13.056Z] 14:39:13     INFO - chrome://mochikit/content/browser-test.js:test_ok:1375
[task 2022-01-24T14:39:13.057Z] 14:39:13     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/head.js:reportUnexpectedFlicker/rects<:633
[task 2022-01-24T14:39:13.058Z] 14:39:13     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/head.js:reportUnexpectedFlicker:624
[task 2022-01-24T14:39:13.059Z] 14:39:13     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/head.js:withPerfObserver:693
INFO - data:image/png;base64
INFO - data:image/png;base64
 INFO - Not taking screenshot here: see the one that was previously logged
[task 2022-01-24T14:39:13.238Z] 14:39:13     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_tabopen.js | should have 0 unknown flickering areas - Got 1, expected +0
[task 2022-01-24T14:39:13.239Z] 14:39:13     INFO - Stack trace:
[task 2022-01-24T14:39:13.240Z] 14:39:13     INFO - chrome://mochikit/content/browser-test.js:test_is:1403
[task 2022-01-24T14:39:13.241Z] 14:39:13     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/head.js:reportUnexpectedFlicker:650
[task 2022-01-24T14:39:13.242Z] 14:39:13     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/head.js:withPerfObserver:693
[task 2022-01-24T14:39:13.242Z] 14:39:13     INFO - Leaving test bound 
[task 2022-01-24T14:39:13.243Z] 14:39:13     INFO - GECKO(4279) | MEMORY STAT | vsize 20984129MB | residentFast 1888MB
[task 2022-01-24T14:39:13.244Z] 14:39:13     INFO - TEST-OK | browser/base/content/test/performance/browser_tabopen.js | took 1491ms

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Dao, do you know how to best deal with this? This is not totally unexpected, and before it was happening just racily because of the delay in setting visibility... Should I just whitelist the rect?

Comment 2

[Daniel Holbert [:dholbert]]

So this is from browser_tabopen.js's usage of withPerfObserver which takes an allowed list of differing-rects and complains if there are changes that don't match that list.

The data URI screenshots show Firefox...
(1) just as the new tab is starting to appear (its "x" is barely visible, nothing else)
(2) after the new tab has finished opening.

This seems fine. The differences between the two are entirely contained in the tab-strip (in the area that the new tab occupies).

And browser_tabopen.js seems to intend to allow differences there, per its comment // We expect all changes to be within the tab strip.

So: seems like we likely need to adjust/add to the allowed-rect-list here.

Comment 3

[Daniel Holbert [:dholbert]]

Attachment: screenshot before the reported "flicker"

Comment 4

[Daniel Holbert [:dholbert]]

Attachment: screenshot after the reported "flicker"

Comment 5

[Daniel Holbert [:dholbert]]

Attachment: diffs between the two screenshots (produced by imagemagick `compare`)

Comment 6

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1751733 - Refactor condition for readability in browser_tabopen.js. r=florian

Comment 7

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1751733 - Account for some padding in exception. r=florian

From looking at the screenshot I think this should do, but lmk if you
think otherwise or I got the wrong padding here... Also dump more
information for the next time the test fails.

Depends on D136783

Comment 8

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1751733 - Dump some debug info in test. r=florian

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/393e2d7c6bd5
Refactor condition for readability in browser_tabopen.js. r=florian

Comment 10

[Narcis Beleuzu [:NarcisB]]

Emilio, the changes didn`t fix the failure.
The failure rate it is still high -> https://treeherder.mozilla.org/jobs?repo=autoland&selectedTaskRun=X8OqIXoXSce7n2fLFcLQFw.0&resultStatus=success%2Ctestfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=393e2d7c6bd57457f2d1f9981151e8c46296a8ca&searchStr=linux%2C18.04%2Cx64%2Cwebrender%2Casan%2Copt%2Cmochitests%2Cwith%2Csoftware%2Cwebrender%2Cand%2Cfission%2Cenabled%2Ctest-linux1804-64-asan-qr%2Fopt-mochitest-browser-chrome-swr-fis-e10s%2Cbc4

Comment 11

[Emilio Cobos Álvarez (:emilio)]

Yes, that's expected, see the other two patches.

Comment 12

[Daniel Holbert [:dholbert]]

Note (given that the fixes are pending review): if the failure rate is painfully high and is a burden on sheriffs, I think it'd be fine to backout bug 1751484 for now (which should stop the failures), and we can re-land that bug's patch once we've got a full stack of r+'d patches here.

Comment 13

[Intermittent Failures Robot]

193 failures in 585 pushes (0.33 failures/push) were associated with this bug yesterday.

** This test has failed more than 150 times in the last 21 days. It should be disabled until it can be fixed. **

Repository breakdown:

• autoland: 172
• mozilla-central: 21

Platform and build breakdown:

• linux1804-64-asan-qr: 53
  • opt: 53
• linux1804-64-qr: 69
  • debug: 25
  • opt: 44
• windows7-32-qr: 4
  • opt: 4
• windows10-64-2004-qr: 23
  • debug: 16
  • opt: 7
• linux1804-64-shippable-qr: 15
  • opt: 15
• windows10-64-2004-shippable-qr: 8
  • opt: 8
• windows10-32-2004-qr: 4
  • debug: 4
• windows10-64-2004-asan-qr: 3
  • opt: 3
• macosx1100-64-shippable-qr: 8
  • opt: 8
• linux1804-64-tsan-qr: 3
  • opt: 3
• linux1804-64-ccov-qr: 1
  • opt: 1
• windows7-32-shippable-qr: 1
  • opt: 1
• windows10-64-2004-ccov-qr: 1
  • opt: 1

For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1751733&startday=2022-01-24&endday=2022-01-24&tree=all

Comment 14

[Cristian Tuns]

This happens on windows too: https://treeherder.mozilla.org/logviewer?job_id=365321255&repo=autoland

Comment 15

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/393e2d7c6bd5

Comment 16

[Andreea Pavel [:apavel]]

Recent failures have been fixed by backout: https://hg.mozilla.org/integration/autoland/rev/302ff8c8329a7fcf31571b700e62873512a679d4

Comment 17

[Intermittent Failures Robot]

155 failures in 697 pushes (0.222 failures/push) were associated with this bug yesterday.

** This test has failed more than 150 times in the last 21 days. It should be disabled until it can be fixed. **

Repository breakdown:

• autoland: 101
• try: 24
• mozilla-central: 30

Platform and build breakdown:

• linux1804-64-qr: 38
  • debug: 12
  • opt: 26
• linux1804-64-asan-qr: 18
  • opt: 18
• linux1804-64-tsan-qr: 1
  • opt: 1
• windows10-64-2004-qr: 34
  • opt: 10
  • debug: 24
• windows10-64-2004-asan-qr: 16
  • opt: 16
• windows10-32-2004-qr: 4
  • debug: 4
• windows7-32-qr: 7
  • opt: 7
• windows10-64-2004-shippable-qr: 10
  • opt: 10
• linux1804-64-shippable-qr: 12
  • opt: 12
• macosx1100-64-shippable-qr: 5
  • opt: 5
• linux1804-64-ccov-qr: 2
  • opt: 2
• windows7-32-shippable-qr: 2
  • opt: 2
• windows10-64-2004-ccov-qr: 2
  • opt: 2
• linux1804-64-devedition-qr: 2
  • opt: 2
• windows10-64-2004-devedition-qr: 2
  • opt: 2

For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1751733&startday=2022-01-25&endday=2022-01-25&tree=all

Comment 18

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/279369667f3a
Dump some debug info in test. r=Gijs

Comment 19

[Atila Butkovits]

https://hg.mozilla.org/mozilla-central/rev/279369667f3a

Comment 20

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1751733 - Account for tab close icon size in browser_tabopen.js. r=florian,Gijs

Whether the overflow happens intentionally or not, it wasn't caused by
the regressing patch so I think we should probably just do this for now.

Comment 21

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/086074bf3060
Account for tab close icon size in browser_tabopen.js. r=florian

Comment 22

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/086074bf3060

Comment 23

[Intermittent Failures Robot]

365 failures in 3445 pushes (0.106 failures/push) were associated with this bug in the last 7 days.

This is the #1 most frequent failure this week.

** This test has failed more than 150 times in the last 21 days. It should be disabled until it can be fixed. **

Repository breakdown:

• autoland: 282
• mozilla-central: 52
• try: 31

Platform and build breakdown:

• linux1804-64-asan-qr: 71
  • opt: 71
• linux1804-64-qr: 110
  • debug: 38
  • opt: 72
• windows7-32-qr: 11
  • opt: 11
• windows10-64-2004-qr: 66
  • debug: 44
  • opt: 22
• windows10-32-2004-qr: 10
  • debug: 8
  • opt: 2
• windows10-64-2004-asan-qr: 19
  • opt: 19
• linux1804-64-shippable-qr: 29
  • opt: 29
• windows10-64-2004-shippable-qr: 19
  • opt: 19
• macosx1100-64-shippable-qr: 13
  • opt: 13
• linux1804-64-tsan-qr: 4
  • opt: 4
• linux1804-64-ccov-qr: 3
  • opt: 3
• windows7-32-shippable-qr: 3
  • opt: 3
• windows10-64-2004-ccov-qr: 3
  • opt: 3
• linux1804-64-devedition-qr: 2
  • opt: 2
• windows10-64-2004-devedition-qr: 2
  • opt: 2

For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1751733&startday=2022-01-24&endday=2022-01-30&tree=all