Long delays in Maya if opening render settings with IPR running

[GregCooper]

I've noticed this ever since updating to Vray 5. Not sure what changed from V-Ray Next to 5 but there is always a delay in responseviness when opening the render settings with an IPR running (GPU only), and I think even with standard renders. In lighter scenes the delay isn't too much of an issue, with heavier scenes the delay can be 30s - 1minute long. This is in Maya btw

I'll pre-empt someone advising not to use the display GPU because this wasn't the case with Vray Next even when using the display GPU so something must have changed between versions.

This has been the case for me across two systems now, an older one with 1080tis which I assumed was maybe due to updated software and older hardware... but now also on a new machine with 3090 GPUs. It just has the effect of slowing my workflow down and making VRay feel sluggish to use.

Anyone else have this experience?

[Muhammed_Hamed]

Hey!

Do you use "Low GPU Thread Priority" for this?
If you are using the same GPU for display and GPU rendering, this option might be helpful



You can also lower the Ray Bundle Size to 64 or 32, this will put less pressure on the GPU and may reduce lags

On 3 machines here I cannot reproduce this lag, one machine uses 3060 for Display and dedicated 3090 for rendering
Using this 3060 for display + Vray GPU there is barely any noticeable lags, the experience is identical to using a 3090(for UI and viewport preformance)

https://www.youtube.com/watch?v=bCV4vt3a5so

For the next release we will rework the low GPU thread priority setting, and it will be selectable per each rendering device.
Could you please record a video of the lags you get on the machine with Ampere GPUs, it will be helpful to us, as well as listing CPU, OS and V-Ray and Nvidia driver versions. Thanks!

Best,
Muhammed

[GregCooper]

Thanks Muhammed, gave all those a try, the only thing that seemed to have an effect was playing with the ray bundle and rays per pixel, but there is still a weird lag when first opening the render settings. Its not a deal breaker but its just behaviour that was never there for me with Vray Next so thought it worth mentioning