Build RAG Chatbot with Llamaindex, Pgvector, Jamba Large, and jina-colbert-v2
Introduction to RAG
Retrieval-Augmented Generation (RAG) is a game-changer for GenAI applications, especially in conversational AI. It combines the power of pre-trained large language models (LLMs) like OpenAI’s GPT with external knowledge sources stored in vector databases such as Milvus and Zilliz Cloud, allowing for more accurate, contextually relevant, and up-to-date response generation. A RAG pipeline usually consists of four basic components: a vector database, an embedding model, an LLM, and a framework.
Key Components We'll Use for This RAG Chatbot
This tutorial shows you how to build a simple RAG chatbot in Python using the following components:
- Llamaindex: a data framework that connects large language models (LLMs) with various data sources, enabling efficient retrieval-augmented generation (RAG). It helps structure, index, and query private or external data, optimizing LLM applications for search, chatbots, and analytics.
- Pgvector: an open-source extension for PostgreSQL that enables efficient storage and querying of high-dimensional vector data, essential for machine learning and AI applications. Designed to handle embeddings, it supports fast approximate nearest neighbor (ANN) searches using algorithms like HNSW and IVFFlat. Since it is just a vector search add-on to traditional search rather than a purpose-built vector database, it lacks scalability and availability and many other advanced features required by enterprise-level applications. Therefore, if you prefer a much more scalable solution or hate to manage your own infrastructure, we recommend using Zilliz Cloud, which is a fully managed vector database service built on the open-source Milvus and offers a free tier supporting up to 1 million vectors.)
- Jamba Large: Jamba Large is a robust language model built for high-performance tasks requiring deep contextual understanding. It offers strong capabilities in generating complex responses and handling intricate queries, making it ideal for advanced applications like virtual assistants, content creation, and conversational AI in enterprise solutions.
- Jina-ColBERT-v2: A dense passage retrieval model optimized for semantic search and document ranking. It combines ColBERT's contextualized late interaction with efficient indexing, delivering high accuracy in understanding query intent and matching relevant text. Ideal for large-scale enterprise search, Q&A systems, and content discovery platforms requiring nuanced semantic understanding and rapid retrieval.
By the end of this tutorial, you’ll have a functional chatbot capable of answering questions based on a custom knowledge base.
Note: Since we may use proprietary models in our tutorials, make sure you have the required API key beforehand.
Step 1: Install and Set Up Llamaindex
pip install llama-index
Step 2: Install and Set Up Jamba Large
%pip install llama-index-llms-ai21
from llama_index.llms.ai21 import AI21
llm = AI21(
model="jamba-large", api_key=api_key, max_tokens=100, temperature=0.5
)
Step 3: Install and Set Up jina-colbert-v2
%pip install llama-index-embeddings-jinaai
You may also need other packages that do not come direcly with llama-index.
!pip install Pillow
from llama_index.embeddings.jinaai import JinaEmbedding
embed_model = JinaEmbedding(
api_key=jinaai_api_key,
model="jina-colbert-v2",
# choose `retrieval.passage` to get passage embeddings
task="retrieval.passage",
)
Step 4: Install and Set Up Pgvector
%pip install llama-index-vector-stores-postgres
from llama_index.core import VectorStoreIndex
from llama_index.vector_stores.postgres import PGVectorStore
vector_store = PGVectorStore.from_params(
database=db_name,
host=url.host,
password=url.password,
port=url.port,
user=url.username,
table_name="your_table_name",
embed_dim=1536, # openai embedding dimension
hnsw_kwargs={
"hnsw_m": 16,
"hnsw_ef_construction": 64,
"hnsw_ef_search": 40,
"hnsw_dist_method": "vector_cosine_ops",
},
)
Step 5: Build a RAG Chatbot
Now that you’ve set up all components, let’s start to build a simple chatbot. We’ll use the Milvus introduction doc as a private knowledge base. You can replace it with your own dataset to customize your RAG chatbot.
import requests
from llama_index.core import SimpleDirectoryReader
# load documents
url = 'https://raw.githubusercontent.com/milvus-io/milvus-docs/refs/heads/v2.5.x/site/en/about/overview.md'
example_file = 'example_file.md' # You can replace it with your own file paths.
response = requests.get(url)
with open(example_file, 'wb') as f:
f.write(response.content)
documents = SimpleDirectoryReader(
input_files=[example_file]
).load_data()
print("Document ID:", documents[0].doc_id)
storage_context = StorageContext.from_defaults(vector_store=vector_store)
index = VectorStoreIndex.from_documents(
documents, storage_context=storage_context, embed_model=embed_model
)
query_engine = index.as_query_engine(llm=llm)
res = query_engine.query("What is Milvus?") # You can replace it with your own question.
print(res)
Example output
Milvus is a high-performance, highly scalable vector database designed to operate efficiently across various environments, from personal laptops to large-scale distributed systems. It is available as both open-source software and a cloud service. Milvus excels in managing unstructured data by converting it into numerical vectors through embeddings, which facilitates fast and scalable searches and analytics. The database supports a wide range of data types and offers robust data modeling capabilities, allowing users to organize their data effectively. Additionally, Milvus provides multiple deployment options, including a lightweight version for quick prototyping and a distributed version for handling massive data scales.
Optimization Tips
As you build your RAG system, optimization is key to ensuring peak performance and efficiency. While setting up the components is an essential first step, fine-tuning each one will help you create a solution that works even better and scales seamlessly. In this section, we’ll share some practical tips for optimizing all these components, giving you the edge to build smarter, faster, and more responsive RAG applications.
LlamaIndex optimization tips
To optimize LlamaIndex for a Retrieval-Augmented Generation (RAG) setup, structure your data efficiently using hierarchical indices like tree-based or keyword-table indices for faster retrieval. Use embeddings that align with your use case to improve search relevance. Fine-tune chunk sizes to balance context length and retrieval precision. Enable caching for frequently accessed queries to enhance performance. Optimize metadata filtering to reduce unnecessary search space and improve speed. If using vector databases, ensure indexing strategies align with your query patterns. Implement async processing to handle large-scale document ingestion efficiently. Regularly monitor query performance and adjust indexing parameters as needed for optimal results.
pgvector optimization tips
To optimize pgvector in a Retrieval-Augmented Generation (RAG) setup, consider indexing your vectors using GiST or IVFFlat to significantly speed up search queries and improve retrieval performance. Make sure to leverage parallelization for query execution, allowing multiple queries to be processed simultaneously, especially for large datasets. Optimize memory usage by tuning the vector storage size and using compressed embeddings where possible. To further enhance query speed, implement pre-filtering techniques to narrow down search space before querying. Regularly rebuild indexes to ensure they are up to date with any new data. Fine-tune vectorization models to reduce dimensionality without sacrificing accuracy, thus improving both storage efficiency and retrieval times. Finally, manage resource allocation carefully, utilizing horizontal scaling for larger datasets and offloading intensive operations to dedicated processing units to maintain responsiveness during high-traffic periods.
Jamba Large optimization tips
Optimizing Jamba Large in a RAG setup involves utilizing its advanced capabilities for complex queries and multi-turn conversations. Leverage fine-tuning to improve domain-specific understanding, ensuring that the model can generate more relevant and accurate results. Optimize your retrieval pipeline by using well-structured, concise document chunks that maintain context without overwhelming the model’s input size. Reduce inference time by batching queries when possible and using efficient hardware acceleration, such as GPUs. Experiment with dynamic prompt adjustments to improve response quality, and ensure that document reranking is utilized for highly relevant results during retrieval.
jina-colbert-v2 optimization tips
To optimize jina-colbert-v2 in a RAG setup, ensure input text is preprocessed by truncating or chunking documents to fit its 512-token limit, preserving context. Use batch inference for dense embeddings to maximize GPU utilization. Fine-tune on domain-specific data to improve relevance. Leverage ColBERT’s late interaction by precomputing document embeddings and caching them for faster retrieval. Adjust the compression ratio for query-document token tensors to balance speed and accuracy. Filter irrelevant documents early using metadata to reduce computational overhead. Monitor retrieval latency and accuracy to iteratively refine parameters.
By implementing these tips across your components, you'll be able to enhance the performance and functionality of your RAG system, ensuring it’s optimized for both speed and accuracy. Keep testing, iterating, and refining your setup to stay ahead in the ever-evolving world of AI development.
RAG Cost Calculator: A Free Tool to Calculate Your Cost in Seconds
Estimating the cost of a Retrieval-Augmented Generation (RAG) pipeline involves analyzing expenses across vector storage, compute resources, and API usage. Key cost drivers include vector database queries, embedding generation, and LLM inference.
RAG Cost Calculator is a free tool that quickly estimates the cost of building a RAG pipeline, including chunking, embedding, vector storage/search, and LLM generation. It also helps you identify cost-saving opportunities and achieve up to 10x cost reduction on vector databases with the serverless option.
Calculate your RAG cost
What Have You Learned?
Congratulations! After diving into this tutorial, you’ve taken significant strides toward mastering the exciting integration of a RAG (Retrieval-Augmented Generation) system by harnessing powerful tools such as a robust framework—LlamaIndex, a vector database—Pgvector, a large language model—Jamba Large, and an embedding model—jina-colbert-v2. You've learned how each of these components plays a unique role in creating a dynamic RAG pipeline, allowing you to efficiently retrieve and generate information tailored to specific user queries. With LlamaIndex, you’ve unlocked a streamlined way to manage and curate your data, while Pgvector enables seamless storage and retrieval of high-dimensional embeddings. Coupling these with Jamba Large's language generation capabilities and the sophisticated embeddings from jina-colbert-v2 means you now possess a powerful arsenal for augmenting your projects.
But that’s not all! The tutorial also offered handy optimization tips to enhance your system's performance and even provided a free RAG cost calculator to help you forecast expenses as you scale your innovations. The potential applications of what you’ve learned are limitless, from enhancing customer support with intelligent chatbots to powering content generation tools. So, don't stop here! Dive into building, optimizing, and experimenting with your own RAG applications. Embrace your creativity and let this journey lead you to innovative solutions that can truly make an impact. Go ahead—get started, and let your imagination soar!
Further Resources
🌟 In addition to this RAG tutorial, unleash your full potential with these incredible resources to level up your RAG skills.
- How to Build a Multimodal RAG | Documentation
- How to Enhance the Performance of Your RAG Pipeline
- Graph RAG with Milvus | Documentation
- How to Evaluate RAG Applications - Zilliz Learn
- Generative AI Resource Hub | Zilliz
We'd Love to Hear What You Think!
We’d love to hear your thoughts! 🌟 Leave your questions or comments below or join our vibrant Milvus Discord community to share your experiences, ask questions, or connect with thousands of AI enthusiasts. Your journey matters to us!
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- Introduction to RAG
- Key Components We'll Use for This RAG Chatbot
- Step 1: Install and Set Up Llamaindex
- Step 2: Install and Set Up Jamba Large
- Step 3: Install and Set Up jina-colbert-v2
- Step 4: Install and Set Up Pgvector
- Step 5: Build a RAG Chatbot
- Optimization Tips
- RAG Cost Calculator: A Free Tool to Calculate Your Cost in Seconds
- What Have You Learned?
- Further Resources
- We'd Love to Hear What You Think!
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