KVarN: new KV-cache quant from Huawei. 3–5× KV cache compression with actual speed-up instead of slow-down, and unlike TurboQuant it holds up on reasoning (Apache 2.0, vLLM single flag)

The KV-cache quant race just got more interesting. Huawei just open-sourced KVarN, a KV-cache quantization method under Apache 2.0, drops into vLLM with one flag. Posting because the tradeoff it's claiming is genuinely different from what's already in the stack, and I'd like to see it stress-tested.