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arXiv · 2203.02505

ARM 4-BIT PQ: SIMD-based Acceleration for Approximate Nearest Neighbor Search on ARM

Yusuke Matsui·Yoshiki Imaizumi·Naoya Miyamoto·Naoki Yoshifuji
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Abstract

We accelerate the 4-bit product quantization (PQ) on the ARM architecture. Notably, the drastic performance of the conventional 4-bit PQ strongly relies on x64-specific SIMD register, such as AVX2; hence, we cannot yet achieve such good performance on ARM. To fill this gap, we first bundle two 128-bit registers as one 256-bit component. We then apply shuffle operations for each using the ARM-specific NEON instruction. By making this simple but critical modification, we achieve a dramatic speedup for the 4-bit PQ on an ARM architecture. Experiments show that the proposed method consistently achieves a 10x improvement over the naive PQ with the same accuracy.

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Yusuke Matsui, Yoshiki Imaizumi, Naoya Miyamoto, Naoki Yoshifuji. 2022-03-03. ARM 4-BIT PQ: SIMD-based Acceleration for Approximate Nearest Neighbor Search on ARM. https://arxiv.org/abs/2203.02505

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