Picasso: Memory-Efficient Graph Coloring Using Palettes With Applications in Quantum Computing

S M Ferdous; Reece Neff; Bo Peng; Salman Shuvo; Marco Minutoli; Sayak Mukherjee; Karol Kowalski; Michela Becchi; Mahantesh Halappanavar

arXiv · 2401.06713

Picasso: Memory-Efficient Graph Coloring Using Palettes With Applications in Quantum Computing

S M Ferdous·Reece Neff·Bo Peng·Salman Shuvo·Marco Minutoli·Sayak Mukherjee·Karol Kowalski·Michela Becchi·Mahantesh Halappanavar

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Abstract

A coloring of a graph is an assignment of colors to vertices such that no two neighboring vertices have the same color. The need for memory-efficient coloring algorithms is motivated by their application in computing clique partitions of graphs arising in quantum computations where the objective is to map a large set of Pauli strings into a compact set of unitaries. We present Picasso, a randomized memory-efficient iterative parallel graph coloring algorithm with theoretical sublinear space guarantees under practical assumptions. The parameters of our algorithm provide a trade-off between coloring quality and resource consumption. To assist the user, we also propose a machine learning model to predict the coloring algorithm's parameters considering these trade-offs. We provide a sequential and a parallel implementation of the proposed algorithm. We perform an experimental evaluation on a 64-core AMD CPU equipped with 512 GB of memory and an Nvidia A100 GPU with 40GB of memory. For a small dataset where existing coloring algorithms can be executed within the 512 GB memory budget, we show up to 68x memory savings. On massive datasets we demonstrate that GPU-accelerated Picasso can process inputs with 49.5x more Pauli strings (vertex set in our graph) and 2,478x more edges than state-of-the-art parallel approaches.

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BibTeX RIS

S M Ferdous, Reece Neff, Bo Peng, Salman Shuvo, Marco Minutoli, Sayak Mukherjee, Karol Kowalski, Michela Becchi, Mahantesh Halappanavar. 2024-02-12. Picasso: Memory-Efficient Graph Coloring Using Palettes With Applications in Quantum Computing. https://arxiv.org/abs/2401.06713

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