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Pixar's Render Farm

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81–90 of 323 posts

Re: Pixar's Render Farm

#81
post #68

Can anyone comment on why Pixar uses standard CPU for processing instead of custom hardware or GPU? I'm wondering why they haven't invested in FPGA or completely custom silicon that speeds up common operations by an order of magnitude. Is each show that different that no common operations are targets for hardware optimization?

FPGA is really expensive for the scale of a modern studio render farm, we're talking around 40~100k cores per datacenter. Because 40~100k cores isn't Google scale either it also doesn't seem to make sense to invest in custom silicon. There's a huge I/O bottleneck as well as you're reading huge textures (I've seen textures as big as 1 TB) and writing constantly to disk the result of the renderer. Other than that, most…

I'm assuming these 1TiB textures are procedural generated or composites? Where do this large of textures come up?

Re: Pixar's Render Farm

#82

Can anyone comment on why Pixar uses standard CPU for processing instead of custom hardware or GPU? I'm wondering why they haven't invested in FPGA or completely custom silicon that speeds up common operations by an order of magnitude. Is each show that different that no common operations are targets for hardware optimization?

In addition to what others have said, I remember reading somewhere that CPUs give more reliably accurate results, and that that's part of why they're still preferred for pre-rendered content

I believe this to be historically true as GPUs often “cheated” with floating point math to optimize hardware pipelines for game rasterization where only looks matter. This is probably not true as GPGPU took hold over the last decade.

Re: Pixar's Render Farm

#83
post #62

Earlier quoted context omitted.

If you're interested in production rendering for films, there's a great deep dive into all the major studio renderers https://dl.acm.org/toc/tog/2018/37/3 As for your questions: > Is rendering of video games more similar to rendering for movies, or VFX? This question is possibly based on an incorrect assumption that feature (animated) films are rendered differently than VFX. They're identical in terms of most tech st…

Thanks! (I was also reading the OP which says "...Our world works quite a bit differently than VFX in two ways..." hence my curiosity)

One way that animated feature films are different than VFX is schedules. Typically, an animated feature from Disney or Pixar will take 4-5 years from start to finish, and everything you see in the movie will need to be created and rendered from scratch.

VFX schedules are usually significantly more compressed, typically 6-12 months, so often times it is cheaper and faster to throw more compute power at a problem rather than paying a group of highly knowledgeable rendering engineers and technical artists to optimize it (although, VFX houses will still employ rendering engineers and technical artists that know about optimization). Pixar has a dedicated group of people called Lightspeed technical artists whose sole job is to optimize scenes so that they can be rendered and re-rendered faster.

Historically, Pixar is also notorious for not doing a lot of "post-work" to their rendered images (although they are slowly starting to embrace it on their most recent films). In other words, what you see on film is very close to what was produced by the renderer. In VFX, to save time, you often render different layers of the image separately and then composite them later in a software package like Nuke. Doing compositing later allows you to fix mistakes, or make adjustments in a faster way than completely re-rendering the entire frame.

Re: Pixar's Render Farm

#84
post #64

Earlier quoted context omitted.

It's very unintuitive that when you open a Thread, the "back" arrow means "back to something else" and you have to scroll up above "line 0" to see the context of the thing being replied to. I forget this every single time I open a tweet thread and try to figure out the context. Once you scroll up, it sort of makes sense -- each tweet with a line connecting user icons but then suddenly the expanded tweet thread has th…

I am not saying it is intuitive. I'm saying it's usable. I'm saying that complaining about it makes people look like they think they're royalty who need everything just so or their whole day is ruined... And now they can't tell the butler to take Poopsie for a walk because they're so shaken by the experience.

I usable all we can expect from one of the world's most popular websites?

Re: Pixar's Render Farm

#85
post #68

Earlier quoted context omitted.

FPGA is really expensive for the scale of a modern studio render farm, we're talking around 40~100k cores per datacenter. Because 40~100k cores isn't Google scale either it also doesn't seem to make sense to invest in custom silicon. There's a huge I/O bottleneck as well as you're reading huge textures (I've seen textures as big as 1 TB) and writing constantly to disk the result of the renderer. Other than that, most…

I'm assuming these 1TiB textures are procedural generated or composites? Where do this large of textures come up?

Can be either. You usually have digital artists creating them.

https://en.wikipedia.org/wiki/Texture_artist

Re: Pixar's Render Farm

#86
post #62

Earlier quoted context omitted.

If you're interested in production rendering for films, there's a great deep dive into all the major studio renderers https://dl.acm.org/toc/tog/2018/37/3 As for your questions: > Is rendering of video games more similar to rendering for movies, or VFX? This question is possibly based on an incorrect assumption that feature (animated) films are rendered differently than VFX. They're identical in terms of most tech st…

Thanks! (I was also reading the OP which says "...Our world works quite a bit differently than VFX in two ways..." hence my curiosity)

I suspect they mean more in approaches to renderfarm utilization and core stealing.

A lot of VFX studios use off the shelf farm management solutions that package up a job as a whole to a node.

I don't believe core stealing like they describe is unique to Pixar, but is also not common outside Pixar either, which is what they allude to afaik. It's less an animation vs VFX comparison, as just studio vs studio infrastructure comparison.

Re: Pixar's Render Farm

#87

Earlier quoted context omitted.

In addition to what others have said, I remember reading somewhere that CPUs give more reliably accurate results, and that that's part of why they're still preferred for pre-rendered content

I believe this to be historically true as GPUs often “cheated” with floating point math to optimize hardware pipelines for game rasterization where only looks matter. This is probably not true as GPGPU took hold over the last decade.

Ah, that makes sense

Re: Pixar's Render Farm

#88

For those that can't stand Twitter's UI: https://threadreaderapp.com/thread/1345146328058269696.html

> JavaScript is not available. We've detected that JavaScript is disabled in this browser. Please enable JavaScript or switch to a supported browser to continue using twitter.com. You can see a list of supported browsers in our Help Center.

So much for Pixar's render farm.

Re: Pixar's Render Farm

#89
post #59
post #47

Earlier quoted context omitted.

It's very painful to follow a conversation on Twitter. I'm not sure why they think the way they've done things makes sense.

It was never supposed to support conversation in the first place. People were supposed to shoot short, simple, single messages and other people maybe react to this with their own short, single messages.

You are describing a chat

Re: Pixar's Render Farm

#90
post #71

In case someone is curious, the optimization they describe is trivial to do in Kubernetes - just enter a resource request for cpu without adding a limit.

It is far from trivial actually. Kubernetes and Render Farms are trying to optimize for very different goals.
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