Revolutionizing GPU Programming with Rust

Host

Welcome to our podcast! Today, we’re diving into an exciting topic that’s making waves in the tech community: running Rust on every GPU. Joining us is Christian Legnitto, the maintainer of Rust GPU and Rust CUDA. Christian, thanks for being here!

Expert

Thanks for having me! I'm excited to talk about this.

Host

To kick things off, can you explain what you mean by running Rust on every GPU? It sounds groundbreaking!

Expert

Absolutely! Traditionally, programming GPUs meant using specialized languages like GLSL or HLSL, which are specific to certain GPU architectures. Our approach with Rust is to compile standard Rust code directly to various GPU targets, which eliminates the need for those complex shader languages.

Host

That sounds like a huge simplification! Can you break down some of the major platforms you’re targeting?

Expert

Sure! We’re supporting CUDA for NVIDIA GPUs, SPIR-V for Vulkan-compatible devices, Metal for Apple, DirectX 12 for Windows, and even WebGPU for browsers. And if someone doesn’t have a GPU, we have a CPU fallback.

Host

Wow, that’s impressive! So, you’ve created a demo that uses a single Rust codebase for all these platforms?

Expert

Yes, this demo showcases a simple bitonic sort algorithm, and the same compute logic runs on every platform. It’s all written in regular Rust without having to switch languages.

Host

For our listeners who might not be familiar, what exactly is a bitonic sort?

Expert

Great question! A bitonic sort is a parallel sorting algorithm that works by dividing an array into two halves and sorting them in opposite directions. It’s particularly well-suited for GPU execution because it can handle multiple data elements simultaneously.

Host

That makes sense! And you mentioned that the code is available on GitHub. Why is sharing it important?

Expert

Sharing it allows other developers to experiment, contribute, and build upon our work. Collaboration is key in open-source projects, and we want to encourage innovation in GPU programming with Rust.

Host

Now, you also talked about the challenges in the GPU terminology. Can you elaborate on that?

Expert

Definitely! Terms like 'Host', 'Device', 'Driver API', and 'Backend' can get pretty confusing. Simply put: the Host is where the Rust code runs on the CPU, the Device is where the compute happens, the Driver API is the interface to communicate with the Device, and the Backend is the Rust library that targets the Driver API.

Host

That clarifies a lot! Now, you mentioned that there are still rough edges to work out. What’s next for the project?

Expert

We have a lot ahead of us! We want to refine the current implementation and expand the features. We’re also exploring the possibility of compiling multiple backends into a single binary, which could really streamline things.

Host

Exciting times ahead! Thank you, Christian, for sharing your insights on Rust GPU. It’s fascinating to see how far we’ve come with GPU programming.

Expert

Thank you for having me! It’s been a pleasure.

Host

And thank you to our listeners for tuning in. Don’t forget to check out the GitHub repository to explore the demo for yourself. Until next time!