Warning Num Samples Per Thread Reduced To 32768 Rendering Might Be Slower Fix | 2026 |

This warning is a specific performance message generated by the rendering engine (developed by ), typically when using GPU rendering (CUDA or RTX engines). Warning Meaning This message indicates that V-Ray has hit a memory (VRAM) ceiling on your graphics card. Chaos Forums

. You are asking the machine to do "brute force" work rather than "smart" work. Lower the Global Max Samples:

While slower than a fully operational GPU render, switching V-Ray entirely to CPU production mode eliminates VRAM hardware limitations. It will leverage your system's RAM, which is far easier and cheaper to expand.

On a technical level, the number 32,768 is a known limit for some GPU resources. For example, on many CUDA‑capable GPUs, . While the sample‑per‑thread cap is not directly the same as register count, both point to a hardware boundary where the rendering engine has to scale back its work distribution to stay within the physical limits of the GPU.

With fewer samples per thread, the system may need to split the workload into more thread batches, increasing overhead. This can reduce performance, especially for complex scenes/high sample counts. This warning is a specific performance message generated

: Excessive use of displacement maps, high-resolution textures (8K+), or V-Ray Fur. SketchUp Community Recommended Actions

: Ensure you are using the latest version of V-Ray, as newer versions have better "out-of-core" texture rendering to handle scenes larger than the VRAM. Chaos Forums Are you rendering a specific high-resolution scene , or does this happen even with simple test files

Adding dozens of render elements (render passes) to a single render job can push VRAM usage over the limit.

Go to your Octane Kernel settings and try these adjustments: You are asking the machine to do "brute

Plan:

Render with vray memory error - Extensions - SketchUp Community

Make sure to include the exact keyword phrase in the title and throughout. Use code blocks for command lines or console output. Provide actionable advice. Write in English. Length: around 1500-2000 words. Understanding the Warning: "Num Samples Per Thread Reduced to 32768, Rendering Might Be Slower"

In the world of high-end rendering—specifically when working with engines like On a technical level, the number 32,768 is

: Check for unnecessary displacement or high-poly models. You can try disabling "Displacement" in Global Swatches to see if memory usage drops significantly. Monitor Memory : Use a tool like

To grasp the warning, we first need to understand how modern renderers handle sampling and threading.

💡 : If you see this warning, your sample settings are likely overkill. Modern AI Denoisers (like OIDN or OptiX) allow you to get clean images at 512–2048 samples, making the 32,768 limit unnecessary for most scenes.

This warning, most commonly seen in and occasionally other GPU renderers like Arnold , indicates that your scene is nearing or has hit the memory (VRAM) ceiling of your graphics card . What This Means