# Real Long-Term Memory for AI: A 50-Million-Token Window That Is Faster and Cheaper Than Recompute > Source: > Published: 2026-10-10 08:21:05+00:00 [Reddit](https://www.reddit.com/r/huggingface/s/x2OAv4Xgee). A large language model can only use the text that fits in its context window, and it recomputes its internal key-value (KV) state for a prompt every time the prompt is sent. We test a memory layer, the public package galahad-kv, that saves the KV state of each block of about 16,000 tokens to encrypted local NVMe disk and loads it back later, byte-exact, without recomputing it. We ran it on 50,000,000 tokens