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Building Meta's GenAI infrastructure

engineering.fb.com

211–220 of 314 posts

Re: Building Meta's GenAI infrastructure

#211

Earlier quoted context omitted.

To date, facebook has built, or is building, 47,100,000 sq ft of space, totaling nearly $24bn in investment. Based on available/disclosed power numbers and extrapolating per sqft, I get something like 4770MW. Last I updated my spreadsheet in 2019, Google had $17bn in investments across their datacenters, totaling 13,260,000 sq ft of datacenter space. Additional buildings have been built since then, but not to the sca…

But Google built data centers aren't the only data centers google is running their machine fleet in...

Yeah, Google buys servers in public datacenters like those from Equinix. One "region" needn't be one datacenter, and sometimes AWS and GCP will even have computers in the same facility. It's actually quite annoying that "region" is such an opaque construct and they don't have any clear way to identify what physical building is hosting the hardware you rent from them.

Re: Building Meta's GenAI infrastructure

#212

So, I'd love to work on optimizing pipelines like this. How does one "get into" it? It seems a ML scientist with some C/C++ and infra knowledge just dips down into the system when required? Or is it CUDA/SIMD experts who move "up" into ML?

start with something small - take some kernel function in C, and try to optimize it for your laptops assembly SIMD instruction set.

Re: Building Meta's GenAI infrastructure

#213

So, I'd love to work on optimizing pipelines like this. How does one "get into" it? It seems a ML scientist with some C/C++ and infra knowledge just dips down into the system when required? Or is it CUDA/SIMD experts who move "up" into ML?

I know someone who works on this in Meta. His resume is computer science heavy, with a masters in Machine Learning. On the previous experience side, before getting into Meta, he had about a decade working as a Software Engineer with Machine Learning system in multiple languages, such as Go, C++ and Python. To get the job he applied for a spot I'm Software Engineer applied in Machine Learning, he went through the mult…

This is helpful thank you. There's always some luck.

I have a PhD in CS, and lots of experience in optimization and some in throughput/speedups (in an amdahl sense) for planning problems. My biggest challenge is really getting something meaty with high constraints or large compute requirements. By the time I get a pipeline set up it's good enough and we move on. So it's tough to build up that skillset to get in the door where the big problems are.

Re: Building Meta's GenAI infrastructure

#214

So, I'd love to work on optimizing pipelines like this. How does one "get into" it? It seems a ML scientist with some C/C++ and infra knowledge just dips down into the system when required? Or is it CUDA/SIMD experts who move "up" into ML?

Our group works on some of this stuff at Meta, and we have a pretty good diversity of backgrounds - high performance computing (the bulk), computer systems, compilers, ML engineers, etc. We are hiring. Feel free to DM me to learn more.

I will, thank you. Any info is very helpful.

Re: Building Meta's GenAI infrastructure

#217

Earlier quoted context omitted.

But Google built data centers aren't the only data centers google is running their machine fleet in...

Yeah, Google buys servers in public datacenters like those from Equinix. One "region" needn't be one datacenter, and sometimes AWS and GCP will even have computers in the same facility. It's actually quite annoying that "region" is such an opaque construct and they don't have any clear way to identify what physical building is hosting the hardware you rent from them.

Those are almost lost in the noise, compared to the big datacenters. (I've been inside two Atlanta facilities, one leased and one built from scratch, and the old Savvis one in Sunnyvale).

Re: Building Meta's GenAI infrastructure

#218

float8 got a mention! x2 more FLOPs! Also xformers has 2:4 sparsity support now so another x2? Is Llama3 gonna use like float8 + 2:4 sparsity for the MLP, so 4x H100 float16 FLOPs? Pytorch has fp8 experimental support, whilst attention is still complex to do in float8 due to precision issues, so maybe attention is in float16, and RoPE / layernorms in float16 / float32, whilst everything else is float8?

care to explain why attention has precision issues with fp8?

Re: Building Meta's GenAI infrastructure

#219
post #174

float8 got a mention! x2 more FLOPs! Also xformers has 2:4 sparsity support now so another x2? Is Llama3 gonna use like float8 + 2:4 sparsity for the MLP, so 4x H100 float16 FLOPs? Pytorch has fp8 experimental support, whilst attention is still complex to do in float8 due to precision issues, so maybe attention is in float16, and RoPE / layernorms in float16 / float32, whilst everything else is float8?

Is it safe to assume this is the same float16 that exists in Apple m2 chips but not m1?

Clarification: bfloat16

“bfloat16 data type and arithmetic instructions (AI and others)”

https://eclecticlight.co/2024/01/15/why-the-m2-is-more-advan...

Re: Building Meta's GenAI infrastructure

#220

Earlier quoted context omitted.

Facebook has more datacenter space and power than Amazon, Google, and Microsoft -- possibly more than Amazon and Microsoft combined...

To date, facebook has built, or is building, 47,100,000 sq ft of space, totaling nearly $24bn in investment. Based on available/disclosed power numbers and extrapolating per sqft, I get something like 4770MW. Last I updated my spreadsheet in 2019, Google had $17bn in investments across their datacenters, totaling 13,260,000 sq ft of datacenter space. Additional buildings have been built since then, but not to the sca…

Does the square footage take into account multiple floors? What's the source? It can be misleading, because you don't know the compute density of what's inside. Using just public data, power is a more accurate proxy. Until at least 5-6 years ago, Google was procuring more electricity than Amazon. Before that, it had a further advantage from lower PUE, but I bet the big names are all comparable on that front by now. Anyone that has worked at several of them can infer that FB is not the largest (but it's still huge).

As for the dollars, were they just in 2019 or cumulative? The Google ones seem low compared to numbers from earnings.

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