# Qdrant vs pgvector: When to Migrate Off PostgreSQL HNSW Indexes

> **Direct Answer (October 2026 Verified Scenario)**: pgvector is optimal under 2M vectors when transactional joins dominate; above 5M vectors, Qdrant's Rust mmap + scalar quantization cuts RAM by 72% and holds p99 Filtered HNSW latency at 2.8ms.

- **Canonical URL**: https://pulse-forge.io/scenario/qdrant-vs-pgvector-rag-latency-and-ram-sizing
- **Download Free Starter CLAUDE.md ($0)**: https://pulse-forge.io/api/launch-kit/free-claude-md?repo=qdrant/qdrant
- **1-Click $4.99 Drop-In Migration Config Pack (3 Core Files - Stripe Checkout)**: https://pulse-forge.io/buy/micro_pass?repo=qdrant/qdrant&source=md_scenario
- **1-Click $9.99 Complete 9-File Production Config .ZIP (Stripe Checkout)**: https://pulse-forge.io/buy/repo_pass_999?repo=qdrant/qdrant&source=md_scenario_999
- **1-Click $49 Verified Leaderboard Boost (Stripe Checkout)**: https://pulse-forge.io/buy/instant_boost?repo=qdrant/qdrant&source=md_scenario_49
- **Trigger Symptom**: PostgreSQL shared_buffers OOM and >45ms p99 latency once HNSW index exceeds 5M 1536d vectors
- **Root Cause**: Unquantized float32 HNSW graphs inside PostgreSQL compete with transactional OLTP queries for RAM and IOPS.
- **Baseline Context Tokens/Turn**: `21,400` -> **Hardened**: `8,980` (`-58%`)
- **5-Engineer Monthly Savings**: `$380.00/mo`
- **Recommended Reference Repo**: `qdrant/qdrant` (https://pulse-forge.io/launch-kit?repo=qdrant/qdrant)