Live data from Hacker News

We were wrong about GPUs

fly.io

291–300 of 604 posts

Re: We were wrong about GPUs

#291
They were double wrong. I work at a GPU cloud provider and we can't bring on the machines fast enough. Demand has been overwhelming.

People aren't going to fly.io to rent GPUs. That's the actual reality here.

They thought they could sidecar it to their existing product offering for a decent revenue boost but they didn't win over the prospect's mind.

Fly has compelling product offerings and boring shovels don't belong in their catalog

Re: We were wrong about GPUs

#292
post #251

Earlier quoted context omitted.

It's worth noting that "container" and "process" are pretty similar abstractions. A lot of people don't realize this, but a container is sort of just a process with a different filesystem root (to oversimplify). That arguably is what a process should be on a server.

No, they are not. I'm not sure who started this whole container is just a process thing, but it's not a good analogy. Quite a lot of things you spin up containers for have multiple processes (databases, web servers, etc). Containers are inherently difficult to sum up in a sentence. Perhaps the most reasonable comparison is to liken them to a "lightweight" vm, but the reasons people use them are so drastically differe…

Having multiple processes under one user in an operating system is more akin to having multiple threads in one process than you think. The processes don't share a virtual memory space or kernel namespaces and they don't share PID namespaces, but that's pretty much all you get from process isolation (malware works because process isolation is relatively weak). The container adds a layer that goes around multiple processes (see cgroups), but the cgroup scheduling/isolation mechanism is very similar to the process isolation mechanism, just with a new root filesystem. Since everything Linux does happens through FDs, a new root filesystem is a very powerful thing to have. That new root filesystem can have a whole new set of libraries and programs in it compared to the host, but that's all you have to do to get a completely new looking computing environment (from the perspective of Python or Javascript).

A VM, in contrast, fakes the existence of an entire computer, hardware and all. That fake hardware comes with a fake disk on which you put a new root filesystem, but it also comes with a whole lot of other virtualization. In a VM, CPU instructions (eg CPUID) can get trapped and executed by the VM to fake the existence of a different processor, and things like network drivers are completely synthetic. None of that happens with containers. A VM, in turn, needs to run its own OS to manage all this fake hardware, while a container gets to piggyback on the management functions of the host and can then include a very minimal amount of stuff in its synthetic root.

Re: We were wrong about GPUs

#293
post #282

Earlier quoted context omitted.

Wild idea: maybe if more devs had good fundamental knowledge to begin with, the good systems engineering could be done along the way.

And if more systems engineers had more design knowledge, navigating the AWS console wouldn’t be like walking on hot coals. But it’s still $X0 billion/year business! We’re all different at good things, and it’s usually better to lean into your strengths than it is to paper over your weaknesses. We can wish everyone were good at everything, or we can try to actually get things done.

  > We can wish everyone were good at everything, or we can try to actually get things done.
False dichotomy. There's no reason we can't have both.

I want to be clear, there's no perfect code or a perfect understanding or any of that. But the complaint here about not knowing /enough/ fundamentals is valid. There is some threshold which we should recognize as a minimum. The disagreement is about where this threshold is, and no one is calling for perfection. But certainly there are plenty who want the threshold to not exist. Be that AI will replace coders or coding bootcamps get you big tech jobs. Zero to hero in a few months is bull.

Re: We were wrong about GPUs

#294
post #219
post #174

Earlier quoted context omitted.

At the company I work for, I routinely mock the software devs for solving every problem by adding yet another layer of abstraction. The piles of abstractions these people levy is mind numbingly absurd. Half the things they are fixing, if not more, are created by the abstractions in the first place.

Yeah, I remember watching a video of (I think?) a European professor who helped with an issue devs were having in developing The Witness. Turns out they had a large algorithm they developed in high level code (~2000 lines of code? can't remember) to place flora in the game world, which took minutes to process, and it was hampering productivity. He looked at it all, and redid almost all of it in something like Frankly…

That really sounds like no one bothered profiling the code. Which I'd say is underengineered, not over.

Re: We were wrong about GPUs

#295
post #282

Earlier quoted context omitted.

And if more systems engineers had more design knowledge, navigating the AWS console wouldn’t be like walking on hot coals. But it’s still $X0 billion/year business! We’re all different at good things, and it’s usually better to lean into your strengths than it is to paper over your weaknesses. We can wish everyone were good at everything, or we can try to actually get things done.

> We can wish everyone were good at everything, or we can try to actually get things done. False dichotomy. There's no reason we can't have both. I want to be clear, there's no perfect code or a perfect understanding or any of that. But the complaint here about not knowing /enough/ fundamentals is valid. There is some threshold which we should recognize as a minimum. The disagreement is about where this threshold is,…

It’s not a false dichotomy at all. You only have so many hours in a day. At a startup, it’s very unlikely (certainly not impossible!) that your differentiation will come from very cheap system orchestration - your time is likely better spent on building your product.

Minimum knowledge is one thing; minimum time to apply it is another.

Re: We were wrong about GPUs

#296

> The biggest problem: developers don’t want GPUs. They don’t even want AI/ML models. They want LLMs. System engineers may have smart, fussy opinions on how to get their models loaded with CUDA, and what the best GPU is. But software developers don’t care about any of that. When a software developer shipping an app comes looking for a way for their app to deliver prompts to an LLM, you can’t just give them a GPU. I'm…

> There's an (increasingly small) group of software developers who don't like "magic" and want to understand where their code is running and what it's doing. These developers gravitate toward open source solutions like Kubernetes Kubernetes is not the first thing that comes to mind when I think of "understanding where their code is running and what it's doing"...

Core kubernetes (deployments, services etc..) is fairly easy to understand. lot of other stuff in the cncf ecosystem is immature. I don't think most people need to use all the operators, admission controllers, otel, service mesh though.

If you're running one team with all services trusting each other, you don't have problems solved by these things. Whenever you introduce a CNCF component outside core kubernetes, invest time in understanding it and why it does what it does. Nothing is "deploy and forget" and will need to be regularly checked and upgraded, and when issues come up you need some architecture-level of the component to troubleshoot because so many moving parts are there.

So if I can get away writing my own cronjob in 1000 lines rather than installing something from GitHub with a helm chart, I will go with the former option.

(Helm is crap though, but you often won't have much choice).

Re: We were wrong about GPUs

#297

Earlier quoted context omitted.

It's more that the God of Moore's Law have given us so many transistors that we are essentially always I/O blocked, so it effectively doesn't matter how good our assembly is for all but the most specialized of applications. Good assembly, bad assembly, whatever, the point is that your thread is almost always going to be blocked waiting for I/O (disk, network, human input) rather than something that a fancy optimizati…

> It's more that the God of Moore's Law have given us so many transistors that we are essentially always I/O blocked this is again just more brash confidence without experience. you're wrong. this is a post about GPUs and so i'll tell you that as a GPU compiler engineer i spend my entire day (work day) staring/thinking about asm in order to affect register pressure and ilp and load/store efficiency etc. > rather than…

I just want to second this. Some of my close friends are PL people working on compilers. I was in HPC before coming to ML, having written a fair amount of CUDA kerenls, a lot of parallelism, and dealing with I/O.

While yes, I/O is often a computational bound, I'd be shy to really say that in a consumer space when we aren't installing flash buffers, performing in situ processing, or even pre-fetching. Hell, in many programs I barely even see any caching! TBH, most stuff can greatly benefit from asynchronous and/or parallel operations. Yeah, I/O is an issue, but I really would not call anything I/O bound until you've actually gotten into parallelism and optimizing code. And even not until you apply this to your I/O operations! There is just so much optimization that a compiler can never do, and so much optimization that a compiler won't do unless you're giving it tons of hints (all that "inline", "const", and stuff you see in C. Not to mention the hell that is template metaprogramming). Things you could never get out of a non-typed language like python, no matter how much of the backend is written in C.

That said, GPU programming is fucking hard. Godspeed you madman, and thank you for your service.

Re: We were wrong about GPUs

#298

> The biggest problem: developers don’t want GPUs. They don’t even want AI/ML models. They want LLMs. System engineers may have smart, fussy opinions on how to get their models loaded with CUDA, and what the best GPU is. But software developers don’t care about any of that. When a software developer shipping an app comes looking for a way for their app to deliver prompts to an LLM, you can’t just give them a GPU. I'm…

> There's an (increasingly small) group of software developers who don't like "magic" and want to understand where their code is running and what it's doing. These developers gravitate toward open source solutions like Kubernetes Kubernetes is not the first thing that comes to mind when I think of "understanding where their code is running and what it's doing"...

If you have a system that's actually big or complex enough to warrant using Kubernetes, which, to be frank, isn't really that much considering the realities of production, the only thing more complex than Kubernetes is implementing the same concepts but half-assed.

I really wonder why this opinion is so commonly accepted by everyone. I get that not everything needs most Kubernetes features, but it's useful. The Linux kernel is a dreadfully complex beast full of winding subsystems and full of screaming demons all over. eBPF, namespaces, io_uring, cgroups, SE Linux, so much more, all interacting with eachother in sometimes surprising ways.

I suspect there is a decent likelihood that a lot of sysadmins have a more complete understanding of what's going on in Kubernetes than in Linux.

Re: We were wrong about GPUs

#299
post #266

Earlier quoted context omitted.

But you just said that you had issues with ceph? How is that not a CSI problem? And CNI problems are extremely normal. Pretty much anyone that didn't just use weavenet and called it a day has had to spend quiet a bit of time to figure it out. If you already know networking by heart it's obviously going to be easier, but few devs do.

Very fair, although with managed services which are increasingly available, you don't typically need to think about CSI or CNI.

Hence

> Kubernetes is not the first thing that comes to mind when I think of "understanding where their code is running and what it's doing"...

Re: We were wrong about GPUs

#300
post #137

I have a timeline that I am still trying to work through but it goes like this : 2012 - moores law basically ends - nand gates do t get smaller just more cleverly wrapped. Single threaded execution more or less stops at 2 GHz and has remained there. 2012-2022 - no one notices single threaded is stalled because everything moves to VMs in the cloud - the excess parallel compute from each generation is just shared out i…

>someone can run their code 1 million times faster than a competitor I’d bet most code we use every day spends most time just waiting for things like disk and network. Not to mention it’s probably inherently sequential.

Most code I use spends time waiting while I solve the captcha.
Post reply on HN