Engineering Shared-Memory Parallel Shuffling to Generate Random Permutations In-Place

This repository contains the source code, relevant raw data, and analysis scripts used in "Engineering Shared-Memory Parallel Shuffling  to Generate Random Permutations In-Place" [Penschuck, SEA 2023]. If you intend to use our Rust implementation, we consider using the rip_shuffle crate.

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Shuffling is the process of placing elements into a random order such that any permutation occurs with equal probability.

It is an important building block in virtually all scientific areas.

We engineer, ---to the best of our knowledge--- for the first time, a practically fast, parallel shuffling algorithm with $\Oh{\sqrt{n}\log n}$ parallel depth that requires only poly-logarithmic auxiliary memory (with high probability).

In an empirical evaluation, we compare our implementations with a number of existing solutions on various computer architectures.

Our algorithms consistently achieve the highest through-put on all machines.

Further, we demonstrate that the runtime of our parallel algorithm is comparable to the time that other algorithms may take to acquire the memory from the operating system to copy the input.