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arXiv · 2403.06898

SFVInt: Simple, Fast and Generic Variable-Length Integer Decoding using Bit Manipulation Instructions

Gang Liao·Ye Liu·Yonghua Ding·Le Cai·Jianjun Chen
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Abstract

The ubiquity of variable-length integers in data storage and communication necessitates efficient decoding techniques. In this paper, we present SFVInt, a simple and fast approach to decode the prevalent Little Endian Base-128 (LEB128) varints. Our approach effectively utilizes the Bit Manipulation Instruction Set 2 (BMI2) in modern Intel and AMD processors, achieving significant performance improvement while maintaining simplicity and avoiding overengineering. SFVInt, with its generic design, effectively processes both 32-bit and 64-bit unsigned integers using a unified code template, marking a significant leap forward in varint decoding efficiency. We thoroughly evaluate SFVInt's performance across various datasets and scenarios, demonstrating that it achieves up to a 2x increase in decoding speed when compared to varint decoding methods used in established frameworks like Facebook Folly and Google Protobuf.

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Gang Liao, Ye Liu, Yonghua Ding, Le Cai, Jianjun Chen. 2024-03-11. SFVInt: Simple, Fast and Generic Variable-Length Integer Decoding using Bit Manipulation Instructions. https://arxiv.org/abs/2403.06898

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