100% CPU constant usage on "Data Decoder" and "GPU"

[rohitsaha29]

Windows 11 Pro 23H2
Intel i7-13700k & 2080ti

Version: [v.129.0.2] AVX2 and AVX

Hardware Acceleration is forced and on, stock no custom user js or anything

[gz83]

Isn't this the expected behavior with HW turned on?

[rohitsaha29]

Isn't this the expected behavior with HW turned on?

No it is not, i have a 100% cpu usage when I have HW acell on. This doesnt happen on stock firefox or any other fork of firefox. This even happens on the normal non AVX build of mercury.

[gz83]

Sorry, I didn't read your description clearly when I was typing that comment a few hours ago on my phone.

Can you confirm that you have installed the HEVC plugin from the Microsoft Store?

[rohitsaha29]

Sorry, I didn't read your description clearly when I was typing that comment a few hours ago on my phone.

Can you confirm that you have installed the HEVC plugin from the Microsoft Store?

Yes I do have it installed.

[Soromeister]

@rohitsaha29 Do you have Intel CPU with Intel Graphics and an NVidia GPU?

[rohitsaha29]

@Soromeister yes i do actually. is there something i need to change or do

[rohitsaha29]

has anyone found or know the fix for this please?

[Soromeister]

@rohitsaha29 I managed to fix this following the below:

• Go to about:config and set these values:

dom.webgpu.enabled = true
dom.webgpu.indirect-dispatch.enabled = true
dom.webgpu.workers.enabled = true
gfx.vsync.force-disable-waitforvblank = true
gfx.webrender.all = true
gfx.webrender.dcomp-video-hw-overlay-win-force-enabled = true
gfx.webrender.triple-buffering.enabled = false
media.hardware-video-decoding.force-enabled = true
security.sandbox.gpu.level = 0

• After doing this, please make sure you close all Mercury processes;
• In your Windows 11, go to Settings > System > Display > Graphics and find Mercury there. If it's not there, add it. Make sure that GPU Preference is set to High Performance with your NVidia GPU listed there.
• Open NVidia Control Panel, go to 3D Settings > Manage 3D Settings > Program Settings and select Mercury from the list, or simply add it via the "Add" button. Once Mercury is added / selected, set it to run using High Performance NVIDIA Processor and, from the list below, set Power Management Mode to Adaptive. Click on Apply to apply the settings.
• Preferably, to make sure this gets applied, reboot your computer and then start Mercury. Using Task Manager, you can monitor which GPU is being used (GPU 0 is Intel, GPU 1 is NVidia). Mercury should now show up as using GPU 1 and you shouldn't get the issue anymore.

[rohitsaha29]

@Soromeister unfortunately this did not work for me. I think its just a issue with mercury itself because my friend was able to replicate it on his system and the same happened for another PC of mine. and this issue doesn't happen on FF Dev or Stable. Hopefully Alex is aware of this issue and can fix it in the next release.

[Soromeister]

Technically, the security.sandbox.gpu.level = 0 should be enough to fix 100% GPU usage. Not sure about that "Data Decoder".

[rohitsaha29]

@Soromeister yeah i don't get it on GPU anymore but I get 100-150% on CPU usage for Data Decoder after all the thing you mentioned applied.