> The contest is open to individuals or teams of individuals who are legal residents or citizens of the United States, United Kingdom, European Union, Canada, New Zealand, or Australia.

In Rust. These are Rust issues, not issues with safety in general.

The issue with bound checks for exemple is entirely avoidable if you prove that all your calls are within bounds before compiling, same thing for partial initialization.

The core issue is that the strategies Rust adopts to ensure memory safety are neither a panacea nor necessarily the right solution in every case. That being said, I think it's a very nice idea to try to write a decoder in Rust and have a bounty for optimization. Rust is popular so work on producing fast and safe Rust is good.

You cannot draw general conclusions by the experiences of one project one time. There are too many confounding factors. There are also projects who have experienced the opposite.

Which is exactly this for video decoders.

In fact, a bounty will show us who really is serious or not and even some interviewers don't have a clue why they ask for 'optimal algorithms' in the first place. Maybe just to show off that they Googled or used ChatGPT for the answer before the interview.

Well, you can't do it for this one. The one who improves this and can explain their changes will have a impressive show of expertise which puts lots of so-called 'SWEs' to shame.

Does that mean that rust devs earn 60k monthly minimum?

What kind of lunatic would pay that kind of money for a dev for a single week

So I doubt it's any religious thing between c and Rust.

1. Desktop - If both implementations run the same but one is faster, you run the faster one to stop the decode spluttering on those borderline cases.

2. Embedded - Where resources are limited, you still go for the faster one, even if it might one day leas to a zero day because you've weighed up the risk and reducing the BOM is an instant win and trying to factor in some unknown code element isn't.

3. Server - You accept media from unknown sources, so you are sandboxed anyway. Losing 5% of computing resources adds up to big $ over a year and at enough scale. At Youtube for example it could be millions of dollars a year of compute doing a decode and then re-encode.

Some other resistances:

1. Energy - If you have software being used in many places over the world, that cost saving is significant in terms of energy usage.

2. Already used - If the C implementation is working without issue, there would be high resistance to spend engineering time to put a slower implementation in.

3. Already C/C++ - If you already have a codebase using the same language, why would you now include Rust into your codebase?

4. Bindings - Commonly used libraries use the C version and are slow to change. The default may remain the C version in the likes of ffmpeg.

I'm really surprised that because something is in Rust and not in C, it would lead people to ignore a 5% performance degradation.

Seriously... when you get something that's 5% faster especially in the video codec space, why would you dismiss it just because it's not in your favorite language... That does sound like a silly reason to dismiss a faster implementation.

Why especially video decoders?

> I wonder if they really care or if this is one of those "we don't want to use Rust because of silly reasons and here's are reasonable-sounding but actually irrelevant technical justification"...

I would have thought video decoders are specifically one of the few cases where performance really is important enough to trump language guaranteed security. They're widely deployed, and need to work in a variety of environments; everything from low power mobile devices to high-throughput cloud infrastructure. They also need to be low latency for live broadcast/streaming.

That's not to say security isn't a concern. It absolutely is, especially given the wide variety of deployment targets. However, video decoders aren't something that necessarily need to continually evolve over time. If you prioritize secure coding practices and pair that with some formal/static analysis, then you ought to be able to squeeze out more performance than Rust. For example, Rust may be inserting bounds checks on repeated access — where as a C program could potentially validate this sort of information just the once up front and pass the "pre-validated" data structure around (maybe even across threads) "knowing" that it's valid data. Yes, there's a security risk involved, but it may be worth it.

There is a reason for this sentence: > « The dav1d and rav1d decoders share the exact same low-level assembly code optimizations—you cannot modify this assembly ».

So, it, kind of, makes the work easier, but it stills very complex I think.

It's similar to job descriptions written for specific candidates they plan to hire. The question shouldn't be "why is this bounty so low?" but "what toolchain makes $20K reasonable for someone?"

Performance work in my experience has been largely organizational friction: running projects in various conditions, collecting evidence maintainers accept, maximizing that limited slice of attention people give my CLs, getting compiler improvements merged. These coordination tasks have become much easier to automate with LLMs (e.g., analyzing maintainer comments to understand cryptic 1 line feedback, what are they actually looking for, what do they mean).

My guess is there's an engineer who's either optimized their feedback cycle to under an hour through specialized tooling (more arrows) or is much better at finding the right signal the first time (more wood). I'd like to understand what tools enable that efficiency.

This is being done to prove a point, that rust is just as efficient as c while being memory safe.

Your idea is misaligned with the goals of the contest and more a moral complaint on “fairness”. Where do you get this notion that any entity offering their own funds in a contest needs to distribute it evenly?

From what I can tell, way more than $20k has been invested into dav1d, and that investment has generated many performance optimisations already. Ostensibly, that's what this rav1d bounty is competing with.

I’m sitting at my desk doing 133t code challenges for free right now. The idea of optimizing something that both matters and could result in a payout of any amount sounds appealing given my context.

I think you underestimate the amount of people willing to do things for free or for the sake of knowledge itself.

And before you suggest that must mean I’m in a dire financial situation, I’m not.

Sounds like a bad way to port. Completely different languages. It took me some time to learn that one cannot simply write C code in Rust and expect the result to be any good. Should've started from scratch.