# IndexShare (IndexShare)

> Nearby layers reuse the token selection computed by one DSA indexer.

Category: Sparse & compressed attention

Computing a DSA indexer in every layer still costs time. IndexShare computes the top-k selection once and lets the following layers (three, in GLM-5.2) reuse it.

The goal is to keep most of the quality of per-layer selection while cutting the indexer overhead.

**Trade-off:** Fewer indexer passes; the selection is slightly less tailored to each layer.

## Models using IndexShare (3)

- [Mistral Large 4 (1T)](https://llm-atlas-7or.pages.dev/models/mistral-large-4.md) — Mistral AI, 2026-10-29
- [Tencent Hy4-preview (770B-A49B)](https://llm-atlas-7or.pages.dev/models/tencent-hy4-preview-770b-a49b.md) — Tencent, 2026-08-28
- [GLM-5.2 (744B)](https://llm-atlas-7or.pages.dev/models/glm-5-2.md) — Z.ai, 2026-06-17

Full explainer with figures by Sebastian Raschka: https://sebastianraschka.com/llm-architecture-gallery/indexshare/
Web page: https://llm-atlas-7or.pages.dev/concepts/indexshare/