Deploy with Cerebrium

Cerebrium is a serverless AI infrastructure platform that makes it easier for companies to build and deploy AI based applications. They offer Serverless GPU's with low cold start times with over 12 varieties of GPU chips that auto scale and you only pay for the compute you use.

Setup Cerebrium

First, we install Cerebrium and login to get authenticated.

pip install cerebrium
cerebrium login

Then let us create our first project

cerebrium init mistral-vllm

Setup Environment and Hardware

You set up your environment and hardware in the cerebrium.toml file that was created using the init function above. Here we are using a Ampere A10 GPU etc. You can read more here

[cerebrium.deployment]
name = "mistral-vllm"
python_version = "3.11"
docker_base_image_url = "debian:bookworm-slim"
include = "[./*, main.py, cerebrium.toml]"
exclude = "[.*]"

[cerebrium.hardware]
cpu = 2
memory = 14.0
compute = "AMPERE_A10"
gpu_count = 1
provider = "aws"
region = "us-east-1"

[cerebrium.dependencies.pip]
sentencepiece = "latest"
torch = ">=2.0.0"
vllm = "latest"
transformers = ">=4.35.0"
accelerate = "latest"
xformers = "latest"

Setup inference

Running code in Cerebrium is like writing normal python with no special syntax. In your main.py specify the following:

from vllm import LLM, SamplingParams
from huggingface_hub import login
from cerebrium import get_secret

# Your huggingface token (HF_AUTH_TOKEN) should be stored in your project secrets on your Cerebrium dashboard
login(token=get_secret("HF_AUTH_TOKEN"))

# Initialize the model
llm = LLM(model="mistralai/Mistral-7B-Instruct-v0.3", dtype="bfloat16", max_model_len=20000, gpu_memory_utilization=0.9)

We need to add our Hugging Face token to our Cerebrium Secrets since using the Mistral model requires authentication. Please make sure the Huggingface token you added, has WRITE permissions. On first deploy, it will download the model and store it on disk therefore for subsequent calls it will load the model from disk.

Add the following to your main.py:

def run(prompt: str, temperature: float = 0.8, top_p: float = 0.75, top_k: int = 40, max_tokens: int = 256, frequency_penalty: int = 1):
  
    sampling_params = SamplingParams(
        temperature=temperature,
        top_p=top_p,
        top_k=top_k,
        max_tokens=max_tokens,
        frequency_penalty=frequency_penalty
    )

    outputs = llm.generate([item.prompt], sampling_params)

    generated_text = []
    for output in outputs:
        generated_text.append(output.outputs[0].text)

    return {"result": generated_text}

Every function in Cerebrium is callable through and API endpoint. Code at the top most layer (ie: not in a function) is instantiated only when the container is spun up the first time so for subsequent calls, it will simply run the code defined in the function you call.

Our final main.py should look like this:

from vllm import LLM, SamplingParams
from huggingface_hub import login
from cerebrium import get_secret

# Your huggingface token (HF_AUTH_TOKEN) should be stored in your project secrets on your Cerebrium dashboard
login(token=get_secret("HF_AUTH_TOKEN"))

# Initialize the model
llm = LLM(model="mistralai/Mistral-7B-Instruct-v0.3", dtype="bfloat16", max_model_len=20000, gpu_memory_utilization=0.9)

def run(prompt: str, temperature: float = 0.8, top_p: float = 0.75, top_k: int = 40, max_tokens: int = 256, frequency_penalty: int = 1):
  
    sampling_params = SamplingParams(
        temperature=temperature,
        top_p=top_p,
        top_k=top_k,
        max_tokens=max_tokens,
        frequency_penalty=frequency_penalty
    )

    outputs = llm.generate([item.prompt], sampling_params)

    generated_text = []
    for output in outputs:
        generated_text.append(output.outputs[0].text)

    return {"result": generated_text}

Run on the cloud

cerebrium deploy

You will see your application deploy, install pip packages and download the model. Once completed it will output a CURL request you can use to call your endpoint. Just remember to end the url with the function you would like to call - in this case /run.

curl --location --request POST 'https://api.cortex.cerebrium.ai/v4/p-<YOUR PROJECT ID>/mistral-vllm/run' \
--header 'Authorization: Bearer <YOUR TOKEN HERE>' \
--header 'Content-Type: application/json' \
--data-raw '{
    "prompt: "What is the capital city of France?"
}'

You should then get a message looking like this:

{
  "run_id": "nZL6mD8q66u4lHTXcqmPCc6pxxFwn95IfqQvEix0gHaOH4gkHUdz1w==",
  "message": "Finished inference request with run_id: `nZL6mD8q66u4lHTXcqmPCc6pxxFwn95IfqQvEix0gHaOH4gkHUdz1w==`",
  "result": {
    "result": ["\nA: Paris"]
  },
  "status_code": 200,
  "run_time_ms": 151.24988555908203
}