e5623d288e
Older weighted_shuffle is based on a heuristic which results in biased
samples as shown in:
https://github.com/solana-labs/solana/pull/18343
and can be replaced with WeightedShuffle.
Also, as described in:
https://github.com/solana-labs/solana/pull/13919
weighted_best can be replaced with rand::distributions::WeightedIndex,
or WeightdShuffle::first.
(cherry picked from commit db23295e1c)
Co-authored-by: behzad nouri <behzadnouri@gmail.com>
29 lines
690 B
Rust
29 lines
690 B
Rust
#![feature(test)]
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extern crate test;
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use {
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rand::{Rng, SeedableRng},
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rand_chacha::ChaChaRng,
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solana_gossip::weighted_shuffle::WeightedShuffle,
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std::iter::repeat_with,
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test::Bencher,
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};
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fn make_weights<R: Rng>(rng: &mut R) -> Vec<u64> {
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repeat_with(|| rng.gen_range(1, 100)).take(1000).collect()
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}
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#[bench]
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fn bench_weighted_shuffle(bencher: &mut Bencher) {
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let mut seed = [0u8; 32];
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let mut rng = rand::thread_rng();
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let weights = make_weights(&mut rng);
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bencher.iter(|| {
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rng.fill(&mut seed[..]);
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WeightedShuffle::new("", &weights)
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.shuffle(&mut ChaChaRng::from_seed(seed))
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.collect::<Vec<_>>()
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});
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}
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