FairyFuse: Multiplication-Free LLM Inference on CPUs via Fused Ternary Kernels
- URL: http://arxiv.org/abs/2604.20913v1
- Date: Wed, 22 Apr 2026 02:42:10 GMT
- Title: FairyFuse: Multiplication-Free LLM Inference on CPUs via Fused Ternary Kernels
- Abstract summary: We present FairyFuse, an inference system that enables multiplication-free execution on commodity CPUs.<n>Roofline analysis shows that 16x weight compression shifts memory-bound GEMV toward the compute regime on bandwidth-limited CPUs.<n>End-to-end, FairyFuse achieves 32.4 tokens per second on a single Intel Xeon 8558P, outperforming llama.
- Score: 2.339485034137561
- License: http://creativecommons.org/publicdomain/zero/1.0/
- Abstract: Large language models are increasingly deployed on CPU-only platforms where memory bandwidth is the primary bottleneck for autoregressive generation. Weight quantization to four bits or below reduces memory pressure, yet existing systems still dequantize weights and perform floating-point multiplications, limiting the achievable gains. Ternary weights in {-1, 0, +1} provide a more efficient alternative, replacing multiplications with conditional additions, subtractions, or no-ops. While Fairy2i shows that ternary LLMs can match FP16 quality, its runtime does not exploit this structure. We present FairyFuse, an inference system that enables multiplication-free execution on commodity CPUs by fusing the eight real-valued sub-GEMVs of each widely-linear layer into a single AVX-512 loop using masked additions and subtractions, with zero floating-point multiplications. Roofline analysis shows that 16x weight compression shifts memory-bound GEMV toward the compute regime on bandwidth-limited CPUs, yielding a 29.6x kernel speedup while offering little benefit on GPUs. End-to-end, FairyFuse achieves 32.4 tokens per second on a single Intel Xeon 8558P, outperforming llama.cpp Q4_K_M by 1.24x with near-lossless quality (WikiText-2 perplexity 5.52 vs. 5.47 FP16; downstream accuracy 66.0%).
Related papers
- Fast NF4 Dequantization Kernels for Large Language Model Inference [10.293114205183166]
Large language models (LLMs) have grown beyond the memory capacity of single GPU devices.<n> NF4 (4-bit NormalFloat) quantization enables 4$times$ memory reduction but requires expensive dequantization back to FP16 format.<n>This paper presents a lightweight shared memory optimization that addresses this gap through principled memory hierarchy exploitation.
arXiv Detail & Related papers (2026-04-02T22:15:57Z) - FPGA Co-Design for Efficient N:M Sparse and Quantized Model Inference [0.8749675983608171]
Large language models (LLMs) have demonstrated remarkable performance across a wide range of language processing tasks.<n>This work introduces an automation framework that leverages weight pruning and low-bit quantization.<n>We present a hardware-software co-design method that generates accelerators on the Field-Programmable Gate Array (FPGA) platform.
arXiv Detail & Related papers (2025-12-31T08:27:40Z) - Bridging the Gap Between Promise and Performance for Microscaling FP4 Quantization [77.67818998672516]
We present the first comprehensive study of MXFP4 and NVFP4 for post-training quantization.<n>We introduce Micro-Rotated-GPTQ (MR-GPTQ), a variant of the classic GPTQ quantization algorithm.<n>We show that MR-GPTQ matches or outperforms state-of-the-art accuracy.
arXiv Detail & Related papers (2025-09-27T09:22:21Z) - APT-LLM: Exploiting Arbitrary-Precision Tensor Core Computing for LLM Acceleration [5.075697428779204]
Large language models (LLMs) have revolutionized AI applications, yet their enormous computational demands severely limit deployment and real-time performance.<n>This is primarily due to the limited support for the GPU Cores, inefficient memory management, and inflexible kernel optimizations.<n>We propose a comprehensive acceleration scheme for arbitrary precision LLMs, namely APT-LLM.
arXiv Detail & Related papers (2025-08-26T14:48:29Z) - SVDQuant: Absorbing Outliers by Low-Rank Components for 4-Bit Diffusion Models [61.474101404805545]
Diffusion models can generate high-quality images, but as they scale, rising memory demands and higher latency pose deployment challenges.<n>We propose SVDQuant, a new 4-bit quantization paradigm to overcome this limitation.<n>We reduce the memory usage for the 12B FLUX.1 models by 3.5$times$, achieving 3.0$times$ speedup over the 4-bit weight-only quantization (W4A16) baseline.
arXiv Detail & Related papers (2024-11-07T18:59:58Z) - COMET: Towards Partical W4A4KV4 LLMs Serving [37.30529940231099]
Quantization is a compression technology to reduce the overhead of serving large language models (LLMs) on terminal devices and in cloud data centers.
We propose a novel mixed-precision quantization algorithm (FMPQ) that compresses most activations into 4-bit with negligible accuracy loss.
We integrate the optimized W4Ax kernel into our inference framework, COMET, and provide efficient management to support popular LLMs.
arXiv Detail & Related papers (2024-10-16T02:16:53Z) - MARLIN: Mixed-Precision Auto-Regressive Parallel Inference on Large Language Models [58.3342517278868]
This paper describes the design of Mixed-precision AutoRegressive LINear kernels.
It shows that batchsizes up to 16-32 can be supported with close to maximum ($4times$) quantization speedup.
MarLIN accomplishes this via a combination of techniques, such as asynchronous memory access, complex task scheduling and pipelining.
arXiv Detail & Related papers (2024-08-21T16:10:41Z) - QServe: W4A8KV4 Quantization and System Co-design for Efficient LLM Serving [52.31791050376249]
Quantization can accelerate large language model (LLM) inference.<n>We introduce QoQ, a W4A8KV4 quantization algorithm with 4-bit weight, 8-bit activation, and 4-bit KV cache.<n>QServe improves the maximum achievable serving of Llama-3-8B by 1.2x on A100, 1.4x on L40S; and Qwen-721.5B by 2.4x on A100, 3.5x on L40S.
arXiv Detail & Related papers (2024-05-07T17:59:30Z) - SmoothQuant+: Accurate and Efficient 4-bit Post-Training
WeightQuantization for LLM [13.035063417593534]
Large language models (LLMs) have shown remarkable capabilities in various tasks.
Currently, 4-bit post-training quantization (PTQ) has achieved some success in LLMs.
We propose SmoothQuant+, an accurate and efficient 4-bit weight-only PTQ.
arXiv Detail & Related papers (2023-12-06T11:10:55Z) - QUIK: Towards End-to-End 4-Bit Inference on Generative Large Language
Models [57.04178959678024]
We show that the majority of inference computations for large generative models can be performed with both weights and activations being cast to 4 bits.
We achieve this via a hybrid quantization strategy called QUIK, which compresses most of the weights and activations to 4-bit.
We provide GPU kernels matching the QUIK format with highly-efficient layer-wise runtimes, which lead to practical end-to-end throughput improvements of up to 3.4x.
arXiv Detail & Related papers (2023-10-13T17:15:05Z) - SpQR: A Sparse-Quantized Representation for Near-Lossless LLM Weight
Compression [76.73007709690306]
We introduce the Sparse-Quantized Representation (SpQR), a new compressed format and quantization technique.
SpQR achieves relative accuracy losses of less than 1% in perplexity for highly-accurate LLaMA and Falcon LLMs.
This makes it possible to run 33B parameter LLM on a single 24 GB consumer GPU without any performance degradation at 15% speedup.
arXiv Detail & Related papers (2023-06-05T17:53:28Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.