Reorder bindings

[FL33TW00D]

@group(0) @binding(0)
var<storage, read> X: array<f32>;

@group(0) @binding(1)
var<storage, read> W: array<f32>;

@group(0) @binding(2)
var<storage, read> B: array<f32>;

@group(0) @binding(3)
var<storage, read_write> Y: array<f32>;

Our kernel preamble currently looks like the following, seems fine right? WRONG! In reality, you want your bindings ordered in ascending order of change.

What does that mean? Your read_write bindgroup should be @group(0) @binding(0), because every operation has a single output. Simple, but boring change to make throughout the codebase.

[AmineDiro]

Hello ! I want to thank you first for this amazing project and I would love to contribute!

I have been looking for this kind of library for a while to write a GPU-powered wasm semantic search module (docvec ) .

As I understand it, to ensure the best performance across the board, you would prefer to have @group(0) contain the values that change least frequently and each @group contain data that changes at progressively higher frequencies. This logic is at group level does it also apply to BindGroupEntries ?

[FL33TW00D]

Hi @AmineDiro, Great to hear that you want to contribute, and docvec already looks very useful!

This issue was quickly written in response to reading the following: https://toji.dev/webgpu-best-practices/bind-groups#grouping-resources-based-on-frequency-of-change

As I understand it, we want to group resources based on frequency of change. Every(?) operation that runs on the GPU has 1 output, whereas the number of inputs is variadic. Therefore, if we reorder the bindings and have the read_write binding in it's own group, then we can avoid changing it!

I'm unsure if it will have a meaningful impact on performance, more reading needs to be done. I try and open these issues when ideas arise, it may not be a fruitful avenue.

Join the discord if you want to contribute/discuss more: https://discord.gg/XFe33KQTG4

[AmineDiro]

Thanks for the prompt response! I'll take a look a look at this and jump on the discord 👍🏼