Engineering Compressed Matrix Multiplication with the Fast Walsh-Hadamard Transform

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Andersson, Joel, Karppa, Matti
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866918289075077120
author Andersson, Joel
Karppa, Matti
author_facet Andersson, Joel
Karppa, Matti
contents We present an implementation of Pagh's compressed matrix multiplication algorithm, a randomized algorithm that constructs sketches of matrices to compute an unbiased estimate of their product. By leveraging fast polynomial multiplication via the FFT, the algorithm achieves high performance when the product matrix is sparse or contains only a small number of entries with magnitudes significantly larger than the rest. We show empirically that the algorithm is practical and can outperform state-of-the-art DGEMM implementations when the product matrix has few nonzero entries or is otherwise dominated by a small subset of elements with large magnitude. As a minor theoretical contribution, we replace the FFT with the Fast Walsh-Hadamard Transform (FWHT) in sketched multiplication, preserving all correctness and variance guarantees of the original algorithm. Experiments with our carefully engineered multithreaded CPU implementation for dense double-precision matrices on 64-core CPU nodes across a range of synthetic benchmarks, exhibiting variable sparsity patterns, show that the FWHT variant is up to 4 times faster than the FFT-based version. Under favorable sparsity and magnitude patterns in the product matrix, our FWHT-based implementation achieves a speedup of up to 40 over DGEMM from Intel MKL, with low probability of error in the estimates. Our implementation is released as free software and comes with NumPy-compatible Python bindings.
format Preprint
id arxiv_https___arxiv_org_abs_2601_09477
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Engineering Compressed Matrix Multiplication with the Fast Walsh-Hadamard Transform
Andersson, Joel
Karppa, Matti
Data Structures and Algorithms
F.2.1
We present an implementation of Pagh's compressed matrix multiplication algorithm, a randomized algorithm that constructs sketches of matrices to compute an unbiased estimate of their product. By leveraging fast polynomial multiplication via the FFT, the algorithm achieves high performance when the product matrix is sparse or contains only a small number of entries with magnitudes significantly larger than the rest. We show empirically that the algorithm is practical and can outperform state-of-the-art DGEMM implementations when the product matrix has few nonzero entries or is otherwise dominated by a small subset of elements with large magnitude. As a minor theoretical contribution, we replace the FFT with the Fast Walsh-Hadamard Transform (FWHT) in sketched multiplication, preserving all correctness and variance guarantees of the original algorithm. Experiments with our carefully engineered multithreaded CPU implementation for dense double-precision matrices on 64-core CPU nodes across a range of synthetic benchmarks, exhibiting variable sparsity patterns, show that the FWHT variant is up to 4 times faster than the FFT-based version. Under favorable sparsity and magnitude patterns in the product matrix, our FWHT-based implementation achieves a speedup of up to 40 over DGEMM from Intel MKL, with low probability of error in the estimates. Our implementation is released as free software and comes with NumPy-compatible Python bindings.
title Engineering Compressed Matrix Multiplication with the Fast Walsh-Hadamard Transform
topic Data Structures and Algorithms
F.2.1
url https://arxiv.org/abs/2601.09477