Caspy7 Reporter
	Description • 7 years ago

Here's a recent post from a redditor.
https://www.reddit.com/r/firefox/comments/76bzmi/possible_solution_to_choppy_1080p_60_fps_youtube/

They indicate getting very poor performance for 1080p 60 FPS YouTube playback (which was not true previously), at least on 56 and 57.  They were able to resolve this by disabling the GPU process.

I've seen several reports of poor video performance with some even indicating that 57 is awesome, except for the video, and I wonder if this may be a part of the reason.

	Jean-Yves Avenard [:jya]
	Comment 2 • 7 years ago

my bad, this was for another bug

	Matt Woodrow (:mattwoodrow)
	Comment 3 • 7 years ago

I can't reproduce this on my machine at least, so could be hardware specific.

Do you know if this happens for all videos, or just h264 ones? The GPU process decoder should only affect h264 videos (unless they have hardware vp9 decoding), but most of youtube is vp9.

About:support for affected users would be really useful, along with the 'stats for nerds' output on affected videos.

	Caspy7 Reporter
	Comment 4 • 7 years ago

> About:support for affected users would be really useful, along with the 'stats for nerds' output on affected videos.

I requested that the original reddit submitter share these details.

I also noticed a comment pointing to previous similar reports on mozillazine:
http://forums.mozillazine.org/viewtopic.php?p=14755116#p14755116
http://forums.mozillazine.org/viewtopic.php?p=14755136#p14755136

I don't really use mozillazine (or haven't in many years) and that post is apparently locked, so I suppose the users could be contacted individually if mozillazine allows it. (Hm, clicking their usernames get's me to an "unable to connect" page.)

That second linked comment says in part:
> GPU Process seems to work very well with Intel GPUs, but not so well with AMD GPUs.

	Jean-Yves Avenard [:jya]
	Comment 5 • 7 years ago

I can't reproduce on my Dell XPS 15 9560.
However,disabling e10s all together makes a massive difference. It goes from jerky to super smooth

	Jean-Yves Avenard [:jya]
	Comment 7 • 7 years ago

Example of impacted graphic adapter (from bug 1418660)
GPU #1
Active: Yes
Description: AMD Radeon (TM) R7 360 Series
Vendor ID: 0x1002
Device ID: 0x665f
Driver Version: 23.20.788.0
Driver Date: 11-2-2017
Drivers: aticfx64 aticfx64 aticfx64 amdxc64 aticfx32 aticfx32 aticfx32 amdxc32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64
Subsys ID: 00000000
RAM: 2048

I can't think of anything on why hardware video decoding would be that impacted by performing the decoding in the GPU process.

	Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)
	Comment 8 • 7 years ago

(In reply to Jean-Yves Avenard [:jya] from comment #7)
> I can't think of anything on why hardware video decoding would be that
> impacted by performing the decoding in the GPU process.

Maybe the compressed frames aren't making it to the GPU process fast enough for some odd reason?

	Markus Igeland
	Comment 9 • 6 years ago

Hi,
I just wanted to chime in that I'm also having very stuttery video playback on 60fps videos, but only when the video if above a certain size. I'm using this video for testing https://www.youtube.com/watch?v=VCterYOoRb0.

When the video is in normal or theater mode, the 60fps video plays very nice. However, if I switch to full screen or the embed-link (semi-full screen (https://www.youtube.com/embed/VCterYOoRb0)), the video will be played showing approximately one frame every one to five seconds, while the audio is playing normally. I can't find anything in the debug info or stats for nerds that suggests the video is not being played normally.

I've tried using h264ify (https://addons.mozilla.org/en-US/firefox/addon/h264ify/) to force youtube to use H.264 instead of VP8/VP9, but the results are the same (except from the codec info in stats for nerds). The same addon can also block 60fps videos, and this makes the problem disappear both for VP8/VP9 and H.264 (although, the video doesn't look as smooth when played at 30fps compared to 60fps, but when 60fps results in 0.2fps the addon definitely is an upgrade).

I've tried all the about:config settings mentioned in both this issue and in https://bugzilla.mozilla.org/show_bug.cgi?id=1418660, but nothing makes a difference.

I'm currently on 57.0.4, and I've tried using beta (59.0b4) and nightly (60.0a1), and the problem is present in all three.

The same issue is present both on my desktop computer and on my laptop. My desktop is running Fedora 27, with an i5 2500k and AMD R9 390 using Mesa 17.2.4. My laptop is running Fedora 26, with an Intel Celeron P4500 using it's integrated GPU, also using Mesa 17.2.4.

If there is any more information I can give from any of my two computers to help find the source of this problem, just say what and I'll provide it.

	Michael MacEachern
	Comment 10 • 6 years ago

I can confirm this issue is still happening on the latest stable version of Firefox as of this writing.  So far it's only happening with videos that are being GPU decoded (H.264, but NOT VP9).

So far my workaround has been setting layers.gpu-process.enabled to false, but leaving media.gpu-process-decoder set to true.  If I set media.gpu-process-decoder to false, then Imgur's newer Beta front page will hard lock up and crash Firefox entirely.  Only problem with this, is that H.264 is no longer GPU accelerated, but it's a compromise I need to make to make this work.

What I have been able to determine with this, is that my AMD Radeon GPU's are the ones affected by this bug, whereas my Nvidia GPU's are working without issue and are not affected by it.

	FancyCicada
	Comment 11 • 5 years ago

I have the same problem but only on linux (Solus). I have 1080 with G-Sync monitor. I noticed that I have smooth video on tiny window, but when I do full screen then I have massive stutters.