腾讯论文发现 MoE 模型的数学、代码等领域技能分散在跨专家的零散神经元中,因此按神经元而非整个专家剪枝可在压缩模型的同时保留大部分能力。其 RAMP 方法按神经元的路由贡献打分,剪掉最无用的 25% 神经元后,6 个模型仍保留 91% 至 98% 的性能。剪掉 50% 神经元时,GPU 显存下降 36% 至 43%,批量 prefill 吞吐提升 17% 至 39%。
New Tencent paper shows domain skills (like math or coding ) in Mixture of Experts models sit in scattered neurons across expert.
so cutting weak neurons instead of whole experts shrinks the models while keeping most skills.
In their experiment, Mixture of Experts AI models kept 91% to 98% of their performance after their least useful 25% of expert neurons were cut.
MoE models send each token to a few experts, which suggests each expert handles a domain like math or code. Other work finds routing mostly tracks token type instead.
They scored each neuron's routed contribution with a measure called RAMP. Neurons picked for one domain overlapped 58% to 74% across samples of that domain, versus 15% to 24% across domains, and sat in mixed experts.
RAMPr prunes by these scores across all experts and kept 91% to 98% of original performance with 75% of neurons left, across 6 models. With 50% left, GPU memory fell 36% to 43% and batched prefill throughput rose 17% to 39%.
If you compress MoE models, prune neurons inside experts by their routed contribution instead of treating each expert as a single unit.
来源:Rohan Paul · x.com