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arXiv · 2601.01444

RadixGraph: A Fast, Space-Optimized Data Structure for Dynamic Graph Storage (Extended Version)

Haoxuan Xie·Junfeng Liu·Siqiang Luo·Kai Wang
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Abstract

Dynamic graphs model many real-world applications, and as their sizes grow, efficiently storing and updating them becomes critical. We present RadixGraph, a fast and memory-efficient data structure for dynamic graph storage. RadixGraph features a carefully designed radix-tree-based vertex index that strikes an optimal trade-off between query efficiency and space among all pointer-array-based radix trees. For edge storage, it employs a hybrid snapshot-log architecture that enables amortized $O(1)$ update time. RadixGraph supports millions of concurrent updates per second while maintaining competitive performance for graph analytics. Experimental results show that RadixGraph outperforms the most performant baseline by up to $16.27\times$ across various datasets in ingesting graph updates, and reduces memory usage by an average of $40.1\%$. RadixGraph is open-source at https://github.com/ForwardStar/RadixGraph.

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Haoxuan Xie, Junfeng Liu, Siqiang Luo, Kai Wang. 2026-01-04. RadixGraph: A Fast, Space-Optimized Data Structure for Dynamic Graph Storage (Extended Version). https://arxiv.org/abs/2601.01444

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