Choosing the right vector database is critical when building high-performance RAG systems and open-source LLM workloads. This breakdown compares pgvector, Pinecone, and Qdrant across performance, hybrid search, cost, scalability, and latency benchmarks — especially for models like LLaMA, Mistral, and Ollama. If you're deploying production-grade private AI or experimenting with local inference, this comparison will help you choose the right stack for your architecture.