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Llama3-8B

Overview

This tutorial explains how to run the model on vLLM using multiple RBLN NPUs. For this guide, we will use the meta-llama/Meta-Llama-3-8B-Instruct model.

Note

Rebellions Scalable Design (RSD) is available on ATOM™+ (RBLN-CA12 and RBLN-CA22) and ATOM™-Max (RBLN-CA25). You can check your RBLN NPU type using the rbln-stat command.

Note

Llama 3 is licensed under the LLAMA Community License, Copyright (c) Meta Platforms, Inc. All Rights Reserved.

Setup & Installation

Before you begin, ensure that your system environment is properly configured and that all required packages are installed. This includes:

Note

Please note that rebel-compiler requires an RBLN Portal account.

Note

Please note that the meta-llama/Meta-Llama-3-8B-Instruct model on HuggingFace has restricted access. Once access is granted, you can log in using the huggingface-cli command as shown below:

$ huggingface-cli login

    _|    _|  _|    _|    _|_|_|    _|_|_|  _|_|_|  _|      _|    _|_|_|      _|_|_|_|    _|_|      _|_|_|  _|_|_|_|
    _|    _|  _|    _|  _|        _|          _|    _|_|    _|  _|            _|        _|    _|  _|        _|
    _|_|_|_|  _|    _|  _|  _|_|  _|  _|_|    _|    _|  _|  _|  _|  _|_|      _|_|_|    _|_|_|_|  _|        _|_|_|
    _|    _|  _|    _|  _|    _|  _|    _|    _|    _|    _|_|  _|    _|      _|        _|    _|  _|        _|
    _|    _|    _|_|      _|_|_|    _|_|_|  _|_|_|  _|      _|    _|_|_|      _|        _|    _|    _|_|_|  _|_|_|_|

    To login, `huggingface_hub` requires a token generated from [https://huggingface.co/settings/tokens](https://huggingface.co/settings/tokens) .
Token: *****

Compile Llama3-8B

To begin, import the RBLNLlamaForCausalLM class from optimum-rbln. This class's from_pretrained() method downloads the Llama 3 model from the HuggingFace Hub and compiles it using the RBLN Compiler. When exporting the model, specify the following parameters:

  • export: Must be True to compile the model.
  • rbln_batch_size: Defines the batch size for compilation.
  • rbln_max_seq_len: Defines the maximum sequence length.
  • rbln_tensor_parallel_size: Defines the number of NPUs to be used for inference.

After compilation, save the model artifacts to disk using the save_pretrained() method. This will create a directory (e.g., rbln-Llama-3-8B-Instruct) containing the compiled model.

from optimum.rbln import RBLNLlamaForCausalLM

# Define the HuggingFace model ID
model_id = "meta-llama/Meta-Llama-3-8B-Instruct"

# Compile the model for 4 RBLN NPUs
compiled_model = RBLNLlamaForCausalLM.from_pretrained(
    model_id=model_id,
    export=True,
    rbln_batch_size=4,
    rbln_max_seq_len=8192,
    rbln_tensor_parallel_size=4,
)

compiled_model.save_pretrained("rbln-Llama-3-8B-Instruct")

Note

You can select an appropriate batch size based on the model size and the specifications of the NPUs. Since vllm-rbln supports continuous batching, it’s important to configure the batch size carefully to ensure optimal throughput and resource utilization. For information on enabling dynamic batching, see Inference with Dynamic Batch Sizes.

Use vLLM API for Inference

Note

Note that for Non-Flash Attention, block_size should match with max_seq_len.

You can use the compiled model with vLLM APIs. The following example shows how to set up the vLLM engine using a compiled model and run inference with it.

from transformers import AutoTokenizer
from vllm import LLM, SamplingParams

# Make sure the engine configuration
# matches the parameters used during compilation.
model_id = "rbln-Llama-3-8B-Instruct"
max_seq_len = 8192
batch_size = 4

llm = LLM(
    model=model_id,
    device="rbln",
    max_num_seqs=batch_size,
    max_num_batched_tokens=max_seq_len,
    max_model_len=max_seq_len,
    block_size=max_seq_len,
)

tokenizer = AutoTokenizer.from_pretrained(model_id)

sampling_params = SamplingParams(
  temperature=0.0,
  skip_special_tokens=True,
  stop_token_ids=[tokenizer.eos_token_id],
)

conversation = [
    {
        "role": "user",
        "content": "What is the first letter of English alphabets?"
    }
]

chat = tokenizer.apply_chat_template(
  conversation, 
  add_generation_prompt=True,
  tokenize=False
)

outputs = llm.generate(chat, sampling_params)
for output in outputs:
    prompt = output.prompt
    generated_text = output.outputs[0].text
    print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")

You can find more vLLM API usage examples for encoder-decoder models and multi-modal models in RBLN Model Zoo.

Please refer to the vLLM Docs for more information on the vLLM API.