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arXiv · 2504.01994

PIM-LLM: A High-Throughput Hybrid PIM Architecture for 1-bit LLMs

Jinendra Malekar·Peyton Chandarana·Md Hasibul Amin·Mohammed E. Elbtity·Ramtin Zand
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Abstract

In this paper, we propose PIM-LLM, a hybrid architecture developed to accelerate 1-bit large language models (LLMs). PIM-LLM leverages analog processing-in-memory (PIM) architectures and digital systolic arrays to accelerate low-precision matrix multiplication (MatMul) operations in projection layers and high-precision MatMul operations in attention heads of 1-bit LLMs, respectively. Our design achieves up to roughly 80x improvement in tokens per second and a 70% increase in tokens per joule compared to conventional hardware accelerators. Additionally, PIM-LLM outperforms previous PIM-based LLM accelerators, setting a new benchmark with at least 2x and 5x improvement in GOPS and GOPS/W, respectively.

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Jinendra Malekar, Peyton Chandarana, Md Hasibul Amin, Mohammed E. Elbtity, Ramtin Zand. 2025-03-31. PIM-LLM: A High-Throughput Hybrid PIM Architecture for 1-bit LLMs. https://arxiv.org/abs/2504.01994

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