AttentionIndex Speeds Learned Sparse Attention on GLM-5.3 and DeepSeek-V4-Flash
The method cuts indexer cost, which accounts for over half of prefill time at one million tokens, without the recall degradation that two-stage block approaches like HiSA suffer as context grows. Serving teams running long-context inference on models with learned sparse attention, such as GLM-5 or DeepSeek-V4, can use it to raise prefill throughput 1.3-1.8 times while preserving retrieval accuracy. Both target models come from Chinese labs, making it directly relevant to practitioners deploying these open-weight models.