[nemanja]

Compute overhead of H.264 encoder is non-negligible for a VM host where I want all my CPU cycles to go to user VMs. Datacenter-class Intel CPUs (Xeon) don't include H.264 encoders in hardware. QuickSync circuitry is generally limited to consumer-grade CPUs. Not to mention MPEG licensing issues.

AV1 eliminates MPEG licensing issues, but encoding in hardware is even more limited. Also, AV1 is great for encode-once use cases (e.g. YouTube) since it's heavily geared towards reducing bandwidth requirements vs. encode speed. It's workable for real-time streaming in the lowest settings, but H.264 is still better overall.

[tlamponi]

Note that this is a bit of a POV thing. For one, CPU cycles handling display also go (indirectly) to your user. And if your users gets a crisper and better picture with less bandwidth due to a modern codec then it can be also seen as win in my book.

Modern CPUs more often have the building blocks included for video encoding, and getting one of those, or a dedicated GPU, probably makes sense if the Users/VMs workload depends on graphical output.

That said, you're definitively also right that it won't be a win for every use case on every hardware, so definitively something to look at more closely, and if it really is worse than the status quo on systems without dedicate GPU and where the CPU has now HW accelleration than the status quo, which I doubt, then adding an opt-out will definitivelys make sense.

[concerndc1tizen]

Wouldn't it also be a problem that, IIUC, a CPU only has one encoding engine, so you could only have one active stream (at full speed), in a multi-tenant scenario?