Large-scale language models (LLMs) have demonstrated outstanding performance on various tasks, but their deployment poses challenges due to their enormous model size. In this paper, we identify that the main challenge in quantizing LLMs stems from the different activation ranges between the channels, rather than just the issue of outliers.We propose a novel reorder-based quantization approach, RPTQ, that addresses the issue of quantizing the activations of LLMs. RPTQ rearranges the channels in the activations and then quantizing them in clusters, thereby reducing the impact of range difference of channels. In addition, we reduce the storage and computation overhead by avoiding explicit reordering. By implementing this approach, we achieved a significant breakthrough by pushing LLM models to 3 bit activation for the first time.
翻译:大规模语言模型(LLMs)在各类任务中展现出卓越性能,但其庞大的模型规模给部署带来挑战。本文指出,量化LLMs的主要挑战源自通道间激活值范围的差异,而不仅仅是异常值问题。我们提出了一种新颖的基于重排序的量化方法RPTQ,专门解决LLMs激活值量化难题。RPTQ通过对激活值的通道进行重排后分簇量化,有效降低了通道间范围差异的影响。此外,我们通过避免显式重排操作来减少存储与计算开销。采用该方法,我们首次成功将LLM模型的激活值量化至3比特,实现了重要突破。