1543980 - Permorange RDD shutdown hang on Win64-Debug

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, defect, P2)

Description

[Andreas Pehrson [:pehrsons]]

Enabling test_streams_element_capture.html to run on all of gPlayTests over in bug 1536766 made mochitest-media for Win10 x64 Debug permorange on a shutdown hang, [1].

Logs are not exactly explicit but what I can read out is:

1. The shutdown hang monitor takes down the parent process: MOZ_CRASH(Shutdown too long, probably frozen, causing a crash.)
2. Main thread is hung in mozilla::ipc::BrowserProcessSubThread::~BrowserProcessSubThread()
3. There's missing leakcheck output from RDD: TEST-UNEXPECTED-FAIL | leakcheck | rdd missing output line for total leaks!

Without too much knowledge this suggests to me that we're hanging waiting for RDD to shut down. It would be interesting to know whether RDD is still doing something, and if so what that is, or if it's gone.

[1] https://treeherder.mozilla.org/#/jobs?repo=try&revision=fe5e5371e66673c637251ca75df66bb8cea4aef6&selectedJob=239895018

Comment 1

[Michael Froman [:mjf]]

This only happens on debug, not opt?

Comment 2

[Andreas Pehrson [:pehrsons]]

Yes. See the treeherder link in comment 0.

Comment 3

[Andreas Pehrson [:pehrsons]]

This is not hit when AV1 is disabled in test_streams_element_capture.html.
https://treeherder.mozilla.org/#/jobs?repo=try&revision=7d37d9c275bed726095a6809ce104a362e722db8

Comment 4

[Alex Chronopoulos [:achronop]]

You could disable RDD, by switching the pref media.rdd-process.enabled, to by sure that the problem lies there.

Comment 5

[Andreas Pehrson [:pehrsons]]

(In reply to Alex Chronopoulos [:achronop] from comment #4)

You could disable RDD, by switching the pref media.rdd-process.enabled, to by sure that the problem lies there.

https://treeherder.mozilla.org/#/jobs?repo=try&revision=736061829991ba1067d6b7ccbd404b5cac5ce3a3

Comment 6

[Andreas Pehrson [:pehrsons]]

Note that bug 1536766 is landing with RDD disabled due to this bug. To repro this again, re-enable RDD by removing the rdd pref we're setting in dom/media/test/test_streams_element_capture.html.

Comment 7

[Karl Tomlinson (:karlt)]

Seems to no longer be an issue without a special media.rdd-process.enabled value and with the test re-enabled.
https://treeherder.mozilla.org/jobs?repo=try&revision=a9297be33999340ab9c65af09187ab00d8d22164

Comment 8

[Karl Tomlinson (:karlt)]

Attachment: Bug 1543980 revert special media.rdd-process.enabled pref value in test_streams_element_capture.html r?#media-playback-reviewers

The shutdown hang no longer occurs and media.rdd-process.enabled=false is
incompatible with media.rdd-process.enabled=false, which is the default on
Nightly since
https://hg.mozilla.org/mozilla-central/rev/e608dfe11fc705c543ec4050ee01403eb5f66a52?revcount=600#l18.18

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/db5ed361f71c
revert special media.rdd-process.enabled pref value in test_streams_element_capture.html r=media-playback-reviewers,alwu

Comment 10

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/db5ed361f71c