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Rohan Paul· @rohanpaul_ai · X·· 2026-07-10AI 评分42
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GLM-5.2 (744B MoE) 可在 25GB 显存的消费级机器上运行,但速度极慢。MoE 架构使每个 token 仅激活约 40B 参数。运行时将密集张量(注意力、嵌入等)常驻 RAM,经 int4 量化后约 9.9GB;路由专家则存储在本地 NVMe 上(约 370GB int4 模型)。解码时仅从磁盘加载被选中的专家权重。冷 token 解码速度仅约 0.05-0.1 tokens/s,需读取约 11GB 专家数据。系统通过 LRU 专家缓存、固定热门专家及 OS 页缓存复用缓解延迟,压缩 MLA KV 缓存降低长上下文内存压力,MTP 投机解码可在缓存预热后提升速度,但冷缓存时可能因验证额外专家而拖慢速度。

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GLM-5.2 (744B MoE) on a 25GB-RAM consumer machine 👌

Very slow, but possible.

MoE changes the memory requirement because each token activates about 40B parameters, not the full model.

Colibrì keeps the dense tensors resident in RAM, including attention, embeddings, and shared components.

Those resident tensors take about 9.9GB after int4 quantization.

The routed experts stay on local NVMe storage as a roughly 370GB int4 model.

During decoding, the router selects experts for each MoE layer and token.

The runtime then loads only those selected expert weights from disk.

This works because inactive experts do not need to occupy RAM.

The main drawback is throughput, not correctness or model size.

A cold token can require about 11GB of expert reads across 75 MoE layers.

That creates very low cold decoding speed, around 0.05 to 0.1 tokens per second.

The system reduces this cost with LRU expert caching, pinned hot experts, and OS page cache reuse.

Compressed MLA KV cache also lowers memory pressure during long context generation.

MTP speculative decoding can improve tokens per forward once the cache is warm.

The same speculation can hurt cold-cache latency because draft verification may load extra experts.

So the design is only possible because MoE sparsity reduces active parameters per token.

The cost is that SSD bandwidth, cache hit rate, and CPU matmul speed dominate latency.

来源:Rohan Paul · x.com