4k (HDR) x265 → 1080p (SDR) x264, slow speed and low resource utilization

[ToiletDuck]

Helluh,

Iam testing an 4K to 1080p encoding currently. 

And to my surprise, i only achieve like near 20 fps.. 

Now, iam using an R9-5900x cpu and Multiple cores peaking at 5.0ghz (PBO2), yet for some reason the encode is going verryy slow.. peaking at 20fps 😐

Have checked a couple filters, and none are cpu/gpu intensive though !  i.e color:basic, detail sharpen, debanding and HDRtoSDR .. that's pretty much it..

Furthermore, cpu utilizes like 30 - 50% , Gpu 12 - 25% .. so very low resources are required for some reason , if you ask me  !?

Did something significant / fundamental changed about the codecs  ?
   
Currently using Hybrid latest 2024.06.16.1 ..


EDIT: Only the Debanding filter is somewhat gpu intensive, and is the bottleneck there, but by 5 - 6 fps.. So yes, i could have sworn i have had more fps with this cpu converting 4K to 1080p in the past..  When using no gpu intesive filters , all cores peak at 4650 Mhz .. so cpu gets utilized for atleast 99% .

Pretty shocked 4K is still a thing for modern cpu's even for gpu (Nvenc) !?

ta ta