# Meta Andromeda retrieval model scores over one billion ads per second

> Original title: Meta Andromeda: Powering the Next Generation of Ads Retrieval Through Model-System Co-Design

- Source: Engineering at Meta
- Published: 2026-10-28T16:00:01.000Z
- Bad Influence: https://badinfluence.news/items/tgahkb519cq1ebp284lj1byj3
- Original: https://engineering.fb.com/2026/10/28/ml-applications/meta-andromeda-next-gen-ads-retrieval-gpu-co-design/

## Summary

Meta's Andromeda ads retrieval system now scores every eligible ad with near ranking-level model performance and surfaces top candidates at over one billion ads per second, a 100x lift over the 2024 system. The new architecture uses LLM-inspired mixture-of-experts and runs at approximately 300x fewer inference-time FLOPs than the 2024 Andromeda retrieval model. Meta says Andromeda has delivered a 2.4% increase in Facebook conversions since 2025.