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

835 B

id type title tags importance confidence created updated
329d3c3d-4cb5-4274-8613-df8bdfa9e3b2 insight Embedding model size barely affects speed — GPU memory bandwidth is the bottleneck
ollama
embedding
performance
gpu
insight
0.7 0.8 2026-02-19T20:53:16.955487+00:00 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.