Hello, Arnold GPU
Arnold render farm
Arnold is one of the most popular **render**ers in animation and film production, the software and **render**ers supported by Fox **Renderfarm** including Arnold, we are also an Arnold **render** farm**. With the recent release of Arnold-188.8.131.52, the first version of the Arnold **GPU** (beta) has been officially released. We can share some of the results and thoughts about the pre-test of the Arnold **GPU**.
The principle of Arnold GPU More than two years ago, Marcos Fajardo (author of the Arnold) talked about the possibility of Arnold GPUs for the first time at SIGGRAPH2015. At the time, a full-platform-supported GPU renderer based on the OpenCL computing framework was designed. However, the current Arnold GPU is based on NVIDIA Optix rendering architecture, the bottom layer is CUDA language, CUDA is much more friendly than OpenCL, the development progress is certainly faster, and the most important thing is that CUDA is faster and more stable. With the release of the RTX series of graphics cards, vector intersection processing is getting faster and faster, and it is more suitable for GPU ray tracing algorithms.
Arnold CPU and GPU effects The original purpose of Arnold GPU rendering was to keep the CPU and GPU rendering results close to each other, which is the effect and speed of the different rendering modes of the beta version. Test environment:
Katana3.0 KtoA 184.108.40.206 gpu19 GeForce GTX 1080 Using 8 render threads Parameter settings: AA samples = 6 GI diffsue samples = 3 GI specular samples = 3 GI transmisson samples = 3 GI diffsue depth = 2 GI specular depth = 3 GI transmisson depth = 8 Light sampling is the default Metal Metal (CPU on the left, GPU on the right) Rendering time: CPU - 2m13s GPU - 10s In summary, the metal BRDF material does not require much computing performance, and can be well calculated on the GPU, so the CPU and GPU noise is less, GPU rendering is much faster. When there are many hard surface materials in the scene, the GPU will show more powerful speed and performance without losing the rendering quality. Glass
Glass (CPU on the left, GPU on the right) Rendering time: CPU - 31m57s GPU - 17s Glass BTDF material, ray tracing renderer is too slow and too inefficient. Although the Arnold GPU renders extremely fast, it is obvious that the rendering details are lost and the noise is dense. Still using the CPU to render slowly is more reliable. Subsurface scattering
Subsurface scattering (CPU on the left, GPU on the right) Rendering time: CPU - 6m39s GPU - 36s Subsurface scattering(SSS), also known as BSSRDF, is the biggest surprise for Arnold GPU in so many tests. The Arnold GPU implements the random_walk BSSRDF in standard_surface. First, the Arnold 5 comes with two types of SSS: Dif Random_walk Diffusion is an empirically based SSS model that renders results faster because many of the parameters are obtained by looking up the table. This empirical model is also commonly used today. Random_walk is a complete light reflection calculation based on a real physical model. Going back to the Arnold GPU, it doesn't support diffusion but uses random_walk directly. The results are perfect, the noise is small, and the rendering is very similar to the CPU. In actual production, this is a CG production requirement that is fully qualified for film. Cornell Box
Cornell_box (CPU on the left, GPU on the right) Rendering time: CPU - 23m37s GPU - 1m27s The result is perfect, although the rendering time is slow, but the effect is amazing. Compared with Redshift, the speed is fiasco, and the effect is over. The biggest problem with Redshift is that indirect lighting tends to be too bright and dark details are not enough. The effect of the Arnold GPU is basically the same as that of the CPU. At this point, it is the best known in the current renderer (prman doesn't know). Please note here that the reason why the rendering time of the GPU is significantly faster than the CPU is because the sampling is the same, and the sampling result is the same, the noise of the GPU rendering result is significantly more than the noise of the CPU rendering result. Arnold Beta Edition Limitations Because Arnold is still in the early beta version, many features are not available. It should be a little early to use the Arnold GPU for production. Here are some of the bigger drawbacks. General restrictions GPU rendering, based on the same sampling, more noise than CPU GPU rendering will read all textures into memory and video memory, not supporting streaming texture GPU rendering does not support bucket rendering, all supported AOVs are left in memory GPU rendering does not support OpenVDB Shaders restrictions OSL Shaders is not supported yet Third-party Shaders are not supported at this time Does not support AOVs write, does not support write_aov Lights restrictions Cylinder_light is not supported yet Disk_light is not supported at this time Mesh_light is not supported yet Light_links is not supported at this time Light_filters is not supported at this time The future of Arnold GPU Arnold wants to use GPU rendering for movie-level projects, but because of the GPU's own shortcomings, many renderings must be calculated using the CPU, which is more efficient. Therefore, it is very important to switch between rendering between CPU and GPU freely. Based on this, Arnold can provide high quality CPU unidirectional ray tracing rendering while providing efficient GPU Optix ray tracing rendering. A set of APIs supports CPU and GPU Arnold was originally designed to use a set of APIs that are compatible with CPU and GPU rendering. Now Arnold GPUs are beginning to be compatible with some of the Maya native materials available in MtoA, at least for this, Arnold has made some progress. Support for OSL Shaders The latest news, from the developer forum, NVIDIA is working with Sony to develop OSL GPU-based compatibility, including several important features of OSL: Closure and LPEs. Will join the Arnold GPU soon. Rendering consistency Now it seems that Arnold still does a good job of restoring effects. GPU rendering tries to move closer to CPU rendering because the two rendering architectures are different and no longer extend. Reference: MIYAZAKI
What Is the Difference Between GPU Mining and GPU Render Farm?
The mining here is a blockchains categoryA blockchain is a shared transaction record database of a system of all participating nodes based on the Bitcoin protocol, which is a publicly available book.Mining is the process of adding transaction records to the public account book. Mining is done by the mining machine. A block contains information such as block headers and transaction data. Among them, the ruler of the blockchain stipulates that the SHA-256 hash value of the block header must start with multiple 0s, which makes the calculation of the hash value difficult, and most of the time requires multiple attempts (each attempt is based on the nonce value) to determine how many zeros the hash value begins, you can get a hash value that is recognized by all nodes in the chain. At this time, you can write transaction data to form a block.Obviously, the more nodes, the more difficult it is to calculate the hash value. The process of calculating this hash value is the mining process.According to the mining ecosystem, mining can be divided into CPU mining, GPU mining, FPGA mining, ASIC mining and so on.CPU Mining The early mining operation method is to use the CPU to calculate the hash value. As the number of blocks increases, the difficulty level of calculating the hash value increases to a certain extent. The electricity cost of the operation exceeds the return obtained by calculating the hash value, and the CPU mining method has no practical value.GPU MiningIt is to use the GPU to calculate the hash value. GPU mining has the advantage of faster computing speed than CPU mining because:The CPU has the computing burden of the system and all programs running on the system;The CPU can execute 4 32-bit (128-bit SSE instructions) operations per clock cycle, while GPUs such as the Radeon HD 5970 can perform 3200 32-bit (3200 ALU instructions) operations. The GPU operation speed is more than 800 times the CPU speed. . Although the CPU can increase its core count to 6, 8, 12, etc., the GPU is still much faster than the CPU.GPU mining is to calculate the hash value of the new block, write the transaction data, generate the block to connect to the blockchain, and obtain virtual currency returns, such as bitcoin, Ethereum, and so on.GPU rendering is the use of GPU computing units for graphics processing, such as calculating the light and material of a pixel in the projection surface of the camera, and finally coloring the pixel, obtaining image information, and writing to a file or displaying it on a display device.A GPU render farm is a network of computing nodes with many GPU devices installed, usually dedicated to GPU rendering to obtain image files. Such as the foxrender**farm.Of course, GPU** render farm can be retrofitted for GPU mining.