1275481 - Suspend background video decoders on timer

Status: RESOLVED FIXED

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

Description

[u480271]

Use a timer to control the suspending of videos in backgrounds tabs so that quick tab away and back doesn't introduce a suspend-then-seek.

Comment 1

[u480271]

Attachment: MozReview Request: Bug 1275481: Suspend video decoding via timer. r?jwwang

Suspend decoding of video in background tabs once timer fires. The timer
is trigger on switch to invisible and reset each time becomes
visible. Default timer is set at 10 seconds and is controlled via pref
media.suspend-bkgnd-video.delay-ms.

Review commit: https://reviewboard.mozilla.org/r/56198/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/56198/

Comment 2

[Chris Pearce [:cpearce (Not reading bugmail)]]

Comment on attachment 8757787 [details]
MozReview Request: Bug 1275481: Suspend video decoding via timer. r?jwwang

I think JW is the best person to review MDSM code now.

Comment 3

[JW Wang [:jwwang] [:jw_wang]]

Comment on attachment 8757787 [details]
MozReview Request: Bug 1275481: Suspend video decoding via timer. r?jwwang

https://reviewboard.mozilla.org/r/56198/#review53030

::: dom/media/MediaDecoderStateMachine.h:936
(Diff revision 1)
> +  // True if video decoding is suspended.
> +  bool mVideoDecodeSuspended;
> +
> +  // Track enabling video decode suspension via timer
> +  RefPtr<MediaTimer> mVideoDecodeSuspendTimer;
> +  MozPromiseRequestHolder<MediaTimerPromise> mVideoDecodeSuspendRequest;

DelayedScheduler should be easier to use.

::: dom/media/MediaDecoderStateMachine.cpp:205
(Diff revision 1)
>        "media.video-queue.send-to-compositor-size", VIDEO_QUEUE_SEND_TO_COMPOSITOR_SIZE);
>    }
>  }
>  
> +// Default delay of 10 seconds.
> +#define SUSPEND_BACKGROUND_VIDEO_DELAY_MS (10*1000)

Favor static const over macro.

::: dom/media/MediaDecoderStateMachine.cpp:211
(Diff revision 1)
> +
>  static bool sSuspendBackgroundVideos = true;
>  
> +// Delay, in milliseconds, that tabs needs to be in background before video
> +// decoding is suspended.
> +static uint32_t sSuspendBackgroundVideoTimerMS;

Use TimeDuration to save worries about confusion between ms and us.

::: dom/media/MediaDecoderStateMachine.cpp:223
(Diff revision 1)
>    static bool sSetupPrefCache = false;
>    if (!sSetupPrefCache) {
>      sSetupPrefCache = true;
>      Preferences::AddBoolVarCache(&sSuspendBackgroundVideos,
>                                   "media.suspend-bkgnd-video.enabled", false);
> +    sSuspendBackgroundVideoTimerMS = Preferences::GetUint(

We should use MediaPrefs whenever possible.

Comment 4

[u480271]

Comment on attachment 8757787 [details]
MozReview Request: Bug 1275481: Suspend video decoding via timer. r?jwwang

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/56198/diff/1-2/

Comment 5

[JW Wang [:jwwang] [:jw_wang]]

Comment on attachment 8757787 [details]
MozReview Request: Bug 1275481: Suspend video decoding via timer. r?jwwang

https://reviewboard.mozilla.org/r/56198/#review53494

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/3206ef153b98
Suspend video decoding via timer. r=jwwang

Comment 7

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/3206ef153b98