claude-memory/graph/insights/embedding-model-size-barely-affects-speed-gpu-memory-bandwid-329d3c.md

13 lines
835 B
Markdown

---
id: 329d3c3d-4cb5-4274-8613-df8bdfa9e3b2
type: insight
title: "Embedding model size barely affects speed — GPU memory bandwidth is the bottleneck"
tags: [ollama, embedding, performance, gpu, insight]
importance: 0.7
confidence: 0.8
created: "2026-02-19T20:53:16.955487+00:00"
updated: "2026-02-19T20:53:16.955487+00:00"
---
nomic-embed-text (137M, F16) and qwen3-embedding:8b (7.6B, Q4_K_M) embed 430 memories in roughly the same time (~27-30s) on RTX 4080 SUPER. Reason: embedding is a single forward pass per batch (not autoregressive generation), texts are short (50-100 tokens), batched 50 at a time (only ~9 batches). GPU memory bandwidth, not compute, is the bottleneck. Quantized 8B model fits in ~5.7GB VRAM. This means there's no practical speed penalty for using the highest quality embedding model that fits in VRAM.