Live data from Hacker News

An Update on Apple M1/M2 GPU Drivers

lwn.net

271–280 of 291 posts

Re: An Update on Apple M1/M2 GPU Drivers

#271

Earlier quoted context omitted.

As a former insider, this is NOT remotely how I would describe reality. I have signed NDAs and don't feel comfortable going into any detail, other than saying that there is a TON going on inside GPUs that is not "basically all emulated".

Maybe a tall ask, but have you considered writing down all your experiences into a book, and release it after all NDAs expire? I’d love to read more about low level hardware and the behind the scenes stuff involved. I’m sure you’ve got a lot of good stories.

Nope in all accounts, I'm afraid.

But, in summary, it was grinding, grinding, and more grinding, with large dollops of impostor syndrome on top of it.

Met lots of nice smart people, but none were as impressive as the folks at NVidia. I was not worthy of being there.

Re: An Update on Apple M1/M2 GPU Drivers

#272

Earlier quoted context omitted.

Maybe a tall ask, but have you considered writing down all your experiences into a book, and release it after all NDAs expire? I’d love to read more about low level hardware and the behind the scenes stuff involved. I’m sure you’ve got a lot of good stories.

> I’d love to read more about low level hardware and the behind the scenes stuff involved. I’m sure you’ve got a lot of good stories. I don't know why you think there's anything resembling "good stories" (I don't even know what would constitute a good story - swash buckling adventures?). It's just grimy-ass runtime/driver/firmware code interfacing with hardware features/flaws.

Exactly right.

95% difficult, stressful and surprisingly tedious work

4% panic, despair, insecurities

1% friendly banter with very smart people

If I had to do it all over again, I wouldn't, even though it allowed me to retire early.

Re: An Update on Apple M1/M2 GPU Drivers

#273
post #75

Earlier quoted context omitted.

> for reasons that go way over my head In fairness to you I think a lot of the stuff involving hardware goes over everyone's heads :D I've seen comments in a number of articles (and I think a few comments in this thread) saying that there are a few features in Vulcan/opengl/direct3d that were standardized ("standardized" in the D3D case?)/required that turned out to be really expensive to implement, hard to implement…

Mesh shaders are actually useful. Or at least game engine people love them, which was not the case for geometry shaders or even tessellation really. They are extremely painful to add support for though. Aside from Apple I don't think any mobile IHVs have a working implementation.

I think (prior to this article) I had assumed they were synonymous :D

Re: An Update on Apple M1/M2 GPU Drivers

#274

Earlier quoted context omitted.

Not really. Tiny Glade is a recent ray-traced title that has no goal of photorealism whatsoever, and it looks gorgeous with RT lighting and shadows: https://youtu.be/QAUSBxxgIbQ You can scale these same principles to even less photorealistic games like the Borderlands series or a Grand Theft Auto game. Ray tracing is less about photorealism (although it is a potent side effect) and more about creating dynamic lightin…

The question isn't " can you achieve your look with RT?" but "do you need RT to achieve your look?". As long as traditional lighting is enough (and given that it has for the last 2 decades or so), RT remains a gimmick.

Let me get this 100% straight, rendering light the exact same way reality itself does it is a gimmick?

In any case, RT isn't just about getting pretty graphics. It massively lowers the artists' workload since there's no need to painstakingly go through each in-game area and add fake lights to make everything look good.

No gaming studio will pass up on the opportunity to get better graphics and better productivity. It really is just a matter of waiting a few years for the hardware to get good enough.

Re: An Update on Apple M1/M2 GPU Drivers

#275
post #102

Earlier quoted context omitted.

You'll have to see what the instruction set / features are capable of, but most likely the "hardware ray tracing" support means it can do ray-BVH and ray-triangle intersection in hardware. You can reuse ray-box and ray-triangle intersection for collision detection. The other parts of ray tracing like shading and so on, are usually just done on the general compute.

> You can reuse ray-box and ray-triangle intersection for collision detection. The problem with doing so, though, and with GPU physics in general is that it's too high latency to incorporate effectively into a typical game loop. It'll work fine for things that don't impact the world, like particle simulations or hair/cloth physics, but for anything interactive the latency cost tends to kill it. That and also the GPU…

I don't follow. You would do intersection tests every frame, right? Run the intersection tests, feed the results into the next frame calculation. Results may be delayed 1 frame, but at 60Hz or 120Hz that isn't really a problem.

Re: An Update on Apple M1/M2 GPU Drivers

#276

Earlier quoted context omitted.

> I’d love to read more about low level hardware and the behind the scenes stuff involved. I’m sure you’ve got a lot of good stories. I don't know why you think there's anything resembling "good stories" (I don't even know what would constitute a good story - swash buckling adventures?). It's just grimy-ass runtime/driver/firmware code interfacing with hardware features/flaws.

Exactly right. 95% difficult, stressful and surprisingly tedious work 4% panic, despair, insecurities 1% friendly banter with very smart people If I had to do it all over again, I wouldn't, even though it allowed me to retire early.

My experience to a T, down to the 1% friendly banter (because while there are lots of smart people working on hardware, almost none of them know how to banter lol).

Re: An Update on Apple M1/M2 GPU Drivers

#277
post #274

Earlier quoted context omitted.

The question isn't " can you achieve your look with RT?" but "do you need RT to achieve your look?". As long as traditional lighting is enough (and given that it has for the last 2 decades or so), RT remains a gimmick.

Let me get this 100% straight, rendering light the exact same way reality itself does it is a gimmick? In any case, RT isn't just about getting pretty graphics. It massively lowers the artists' workload since there's no need to painstakingly go through each in-game area and add fake lights to make everything look good. No gaming studio will pass up on the opportunity to get better graphics and better productivity. It…

> Let me get this 100% straight, rendering light the exact same way reality itself does it is a gimmick?

Yes, because "Rendering light the exact same way reality itself does it" was never the assignment, outside of nvidia desperately trying to find excuses to sell more GPUs.

Maybe some games would benefit from it in some cases... but you have to weigh that marginal improvement against the increased costs, both economic and ecological.

> It massively lowers the artists' workload since there's no need to painstakingly go through each in-game area and add fake lights to make everything look good.

This is a laughable claim, as long as you're going for anything more than fixed ambient lighting you're going to need to massage and QA that the lighting works for what you're trying to show.

---

In short, yes. Ray tracing as a headline feature is a gimmick, made to appeal to the same clueless HNers who think AI will eliminate our need to understand anything or express ourselves.

Re: An Update on Apple M1/M2 GPU Drivers

#278

Earlier quoted context omitted.

> My daily-driver laptop at home is a T420 from 2011 with a Core 2 Duo, SSD and 8GB RAM. Works fine still. I am not sure I would be productive with that. Any Core 2 Duo is 10x slower single core and 20x slower multi-core than a current generation laptop CPU at this point. Eg: https://browser.geekbench.com/v6/cpu/compare/8588187?baselin... I think it would mostly be good as an SSH terminal, but doing any real work loc…

The problem is software, though. I have a X200s with 4 GiB RAM from 2009. It was interesting to see how Firefox got slower and slower over the years. Granted, it not only is Firefox but also retard websites which use loads and loads of JS to display static content in the end. In return, it is not like JS didn't exist back then: The XhtmlRequest thingy for dynamic website updates or whatever the name for that was has…

This depends on the workflow heavily. For working with text, listening to music, or even doing some light paint work my museum 75mhz K5 running windows 2000 is enough. For building a multi-platform python package embedding a compiler you really want lots of cores. At this point we are talking about 20x+ difference between Core 2 Duo and a modern part. For modern day web experience you want something in between.

Re: An Update on Apple M1/M2 GPU Drivers

#279

Earlier quoted context omitted.

> You can reuse ray-box and ray-triangle intersection for collision detection. The problem with doing so, though, and with GPU physics in general is that it's too high latency to incorporate effectively into a typical game loop. It'll work fine for things that don't impact the world, like particle simulations or hair/cloth physics, but for anything interactive the latency cost tends to kill it. That and also the GPU…

I don't follow. You would do intersection tests every frame, right? Run the intersection tests, feed the results into the next frame calculation. Results may be delayed 1 frame, but at 60Hz or 120Hz that isn't really a problem.

It is a problem. You've generated an entire impossible world state and shown it to the user before discovering it's bad and needing to rewind it.

The faster your fps, the more flickery this ends up looking as you're constantly pulling back the camera or player or whatever a frame after it collided. The lower the fps, the more sluggish and unresponsive it feels.

Alternatively you need to pipeline your entire world state and now you've got some pretty bad input latency

Re: An Update on Apple M1/M2 GPU Drivers

#280

Alyssa's solution to the 4KB vs. 16KB page size discrepancy by running everything in a virtual machine feels like both a clever hack and a potential performance bottleneck. It makes me wonder about the long-term implications of such workarounds. Are we reaching a point where the complexity of bridging these gaps outweighs the benefits, especially when dealing with proprietary hardware designed to be a closed ecosyste…

> This closed ecosystem not only complicates the work for open-source contributors but also stifles innovation that could benefit all users.

from their perspective, motivated devs are doing all the heavy-lifting for them. from this side of ecosystem, they would mainly care about native app compatibility and comparable AI (inference) experience.

both of the above seem to be taken care of, sometimes through combined efforts. other than this, they are happy to lock things down as much as they can get away with. the community unfortunately gravitates towards overall appeal rather than good open initiatives.

Post reply on HN