_A_akhe·Apr 24, 2024
GPU vs CPU:
It's faster to use a GPU. If you tried to play a game on a laptop with onboard gfx vs buying a good external graphics card, it might technically work but a good GPU gives you more processing power and VRAM to make it a faster experience. Same thing here.
When is GPU needed:
You need it for both initial training (which it sounds like you've done) and also when someone prompts the LLM and it parses their query (called inference). So to answer your question - your web server that handles LLM queries coming in also needs a great GPU because with any amount of user activity it will be running effectively 24/7 as users are continually prompting it, as they would use any other site you have online.
When is GPU not needed:
Computationally, inference is just "next token prediction", but depending on how the user enters their prompt som
Read the rest
etimes it's able to provide those predictions (called completions) with pre-computed embeddings, or in other words by performing a simple lookup, and the GPU is not invoked. For example in this autocompletion/token-prediction library I wrote that uses an ngram language model (https://github.com/bennyschmidt/next-token-prediction), GPU is only needed for initial training on text data, but there's no inference component to it - so completions are fast and don't invoke the GPU, they are effectively lookups. An LM like this could be trained offline and deployed cheaply, no cloud GPU needed. And you will notice that LLMs sometimes will work this way, especially with follow-up prompting once it already has the needed embeddings from the initial prompt - for some responses, an LLM is fast like this.
On-prem:
Beyond the GPU requirement, it's not fundamentally different than any other web server. You can buy/build a gaming PC with a decent GPU, forward ports, get a domain, install a cert, run your model locally, and now you have an LLM server online. If you like Raspberry Pi, you might look into the NVIDIA Jetson Nano (https://www.nvidia.com/en-us/autonomous-machines/embedded-sy...) as it's basically a tiny computer like the Pi but with a GPU and designed for AI. So you can cheaply and easily get an AI/LLM server running out of your apartment.
Cloud & serverless:
Hosting is not very different from conventional web servers except that their hardware has more VRAM and their software is designed for LLM access rather than a web backend (different db technologies, different frameworks/libraries). Of course AWS already has options for deploying your own models and there are a number of tutorials showing how to deploy Ollama on EC2. There's also serverless providers - Replicate, Lightning.AI - these are your Vercels and Herokus that you might pay a little more for but get convenience so you can get up and running quickly.
TLDR: It's like any other web server except you need more GPU/VRAM to do training and inference. Whether you want to run it yourself on-prem, host in the cloud, use a PaaS, etc. those are mostly the same decisions as any other project.