CasparCG 2160p6000 Lag issue

Was trying for the first time to go from 1080p6000 to 2160p600 configuration.
I’m using a setup with AMD CPU 3950X and RTX 2080 Ti Xtreme 11G, full SSD with Decklink 4k card

I tried to :

  • Retrieve 1080p6000 input from Decklink card
  • Mix this input into 1920x1080 center of the screen consumer. (Dosn’t change input size)
  • Display to 4K Screen consumer

Using : 2.1.10 NRK, 2.2.0 Stable, 2.2 Last build

Results are not really good whatever casparcg version I use : The video “lags” and is not smooth on the consumer, with CPU going to >60% and performance issue logs on 2.1.10 NRK. (Not seen on 2.2 but I read few months ago the message appears more frequently on 2.1 so I guess this is normal).
Video is “ok” if I put settings below, starting at 2160p3000. (But I didn’t test with many layers / html processing / images / videos that will add more processing and I’m pretty sure in this case I’ll go back to lags)

On the other hand, with the same setup I tried running Vmix with 4k output , which takes my Decklink 1080p60 input and this runs way better without any lag on the output , the processor usage being less than 7%.

Do you know what could cause this huge difference between the two softs ?
What value / data could I provide to help devs to find it?

Thanks ,

The screen consumer is a performance beast. Have you tried using a Decklink card?

I didn’t. I’ll give a try even if I wanted to avoid the use of Decklink card as output (need a 4k model) and make the CG works instead to output to 4K with simple HDMI that I’ll retrieve for my stage screen LED (4k input)

One thing to notice too is that official client (both old and new one) is not able to handle 4k correctly since when I try to add a simple MIXER FILL I’m not able to select values (stay at 0, input is blocked and not able to set anything or use the slider) , sending custom command works though.