# Rock Matrix open-sources EdgeRock-4B, cutting Qwen3.5-4B's 256K KV cache to 72 MiB

> Original title: Rock Matrix Open-Sources EdgeRock-4B, Cutting Qwen3.5-4B's 256K KV Cache From 8 GiB to 72 MiB

- Source: Pandaily
- Published: 2026-10-27T02:52:23.000Z
- Bad Influence: https://badinfluence.news/items/lyxw58delsx1wd8w90hwaf4ko
- Original: https://pandaily.com/rock-matrix-edgerock-4b-open-source-bounded-state-model-qwen3-5-4b-72mib-kv-cache

## Summary

Rock Matrix, with HKUST and Carnegie Mellon University, has open-sourced EdgeRock-4B, a model converted from Alibaba's Qwen3.5-4B. Its KV cache is fixed at 72 MiB at 256K context, against 8 GiB for Qwen3.5-4B, a 99.1% cut. The team reports 6.42 times Qwen's throughput at its batch limit and 96.3% of Qwen's AIME score, with weights released under a license it says allows commercial use.