diff --git a/Cargo.toml b/Cargo.toml index f70f184f..040cf901 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -29,6 +29,16 @@ num_cpus = "1.12.0" [dev-dependencies] rand = "0.7" +rayon = "1.3" +criterion = "0.3" + +[[bench]] +name = "flurry_dashmap" +harness = false + +[[bench]] +name = "flurry_hashbrown" +harness = false [patch.crates-io] crossbeam-epoch = { git = "https://github.com/cynecx/crossbeam.git", branch = "fix-unsoundness" } diff --git a/benches/README.md b/benches/README.md new file mode 100644 index 00000000..9960052d --- /dev/null +++ b/benches/README.md @@ -0,0 +1,35 @@ +## Benchmarks + +Currently, benchmarks following those of [`dashmap`](https://github.com/xacrimon/dashmap/tree/master/benches) and [`hashbrown`](https://github.com/rust-lang/hashbrown/blob/master/benches/bench.rs) are provided. +To compare against other hashmap implementations, the benchmarks located in the respective repositories may be executed. +Note that `flurry`, like `dashmap`, uses [`criterion`](https://docs.rs/criterion/0.3.1/criterion/) (and [`rayon`](https://docs.rs/rayon/1.3.0/rayon/) for parallel testing), while `hashbrown` uses [`test::bench`](https://doc.rust-lang.org/test/bench/index.html). + +To run the `flurry` benchmarks, just run + +```console +$ cargo bench +``` + +or + +```console +$ cargo bench +``` + +to only run benches containing `` in their names. + +To run the original `dashmap` benchmarks: + +```console +$ git clone https://github.com/xacrimon/dashmap.git +$ cd dashmap +$ cargo bench [] +``` + +To run the original `hashbrown` benchmarks: + +```console +$ git clone https://github.com/rust-lang/hashbrown.git +$ cd hashbrown +$ cargo bench [] +``` \ No newline at end of file diff --git a/benches/dashmap.LICENSE b/benches/dashmap.LICENSE new file mode 100644 index 00000000..3c32766b --- /dev/null +++ b/benches/dashmap.LICENSE @@ -0,0 +1,21 @@ +MIT License + +Copyright (c) 2019 Acrimon + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. \ No newline at end of file diff --git a/benches/flurry_dashmap.rs b/benches/flurry_dashmap.rs new file mode 100644 index 00000000..62258fc3 --- /dev/null +++ b/benches/flurry_dashmap.rs @@ -0,0 +1,181 @@ +/* Benchmarks from `dashmap` (https://github.com/xacrimon/dashmap), + * adapted to flurry for comparison: + * + * This benchmark suite contains benchmarks for concurrent insertion + * and retrieval (get). + * Currently, this file provides two versions of each test, one which + * follows the original implementation in using `par_iter().for_each()`, + * which necessitates creating a new guard for each operation since + * guards are not `Send + Sync`, and one version which uses threads + * spawned in scopes. The latter version is able to create only one + * guard per thread, but incurs overhead from the setup of the more + * heavyweight threading environment. + * + * For the associated license information, please refer to dashmap.LICENSE. + */ + +use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion, Throughput}; +use flurry::{epoch, HashMap}; +use rayon; +use rayon::prelude::*; +use std::sync::Arc; + +/* DASHMAP */ +const ITER: u64 = 32 * 1024; + +fn task_insert_flurry_u64_u64_guard_every_it() -> HashMap { + let map = HashMap::with_capacity(ITER as usize); + (0..ITER).into_par_iter().for_each(|i| { + let guard = epoch::pin(); + map.insert(i, i + 7, &guard); + }); + map +} + +fn insert_flurry_u64_u64_guard_every_it(c: &mut Criterion) { + let mut group = c.benchmark_group("insert_flurry_u64_u64_guard_every_it"); + group.throughput(Throughput::Elements(ITER as u64)); + let max = num_cpus::get(); + + for threads in 1..=max { + group.bench_with_input( + BenchmarkId::from_parameter(threads), + &threads, + |b, &threads| { + let pool = rayon::ThreadPoolBuilder::new() + .num_threads(threads) + .build() + .unwrap(); + pool.install(|| b.iter(task_insert_flurry_u64_u64_guard_every_it)); + }, + ); + } + + group.finish(); +} + +fn task_insert_flurry_u64_u64_guard_once(threads: usize) -> HashMap { + let map = Arc::new(HashMap::with_capacity(ITER as usize)); + let inc = ITER / (threads as u64); + + rayon::scope(|s| { + for t in 1..=(threads as u64) { + let m = map.clone(); + s.spawn(move |_| { + let start = t * inc; + let guard = epoch::pin(); + for i in start..(start + inc) { + m.insert(i, i + 7, &guard); + } + }); + } + }); + Arc::try_unwrap(map).unwrap() +} + +fn insert_flurry_u64_u64_guard_once(c: &mut Criterion) { + let mut group = c.benchmark_group("insert_flurry_u64_u64_guard_once"); + group.throughput(Throughput::Elements(ITER as u64)); + let max = num_cpus::get(); + + for threads in 1..=max { + group.bench_with_input( + BenchmarkId::from_parameter(threads), + &threads, + |b, &threads| { + let pool = rayon::ThreadPoolBuilder::new() + .num_threads(threads) + .build() + .unwrap(); + pool.install(|| b.iter(|| task_insert_flurry_u64_u64_guard_once(threads))); + }, + ); + } + + group.finish(); +} + +fn task_get_flurry_u64_u64_guard_every_it(map: &HashMap) { + (0..ITER).into_par_iter().for_each(|i| { + let guard = epoch::pin(); + assert_eq!(*map.get(&i, &guard).unwrap(), i + 7); + }); +} + +fn get_flurry_u64_u64_guard_every_it(c: &mut Criterion) { + let mut group = c.benchmark_group("get_flurry_u64_u64_guard_every_it"); + group.throughput(Throughput::Elements(ITER as u64)); + let max = num_cpus::get(); + + for threads in 1..=max { + let map = task_insert_flurry_u64_u64_guard_every_it(); + + group.bench_with_input( + BenchmarkId::from_parameter(threads), + &threads, + |b, &threads| { + let pool = rayon::ThreadPoolBuilder::new() + .num_threads(threads) + .build() + .unwrap(); + pool.install(|| b.iter(|| task_get_flurry_u64_u64_guard_every_it(&map))); + }, + ); + } + + group.finish(); +} + +fn task_get_flurry_u64_u64_guard_once(threads: usize, map: Arc>) { + let inc = ITER / (threads as u64); + + rayon::scope(|s| { + for t in 1..=(threads as u64) { + let m = map.clone(); + s.spawn(move |_| { + let start = t * inc; + let guard = epoch::pin(); + for i in start..(start + inc) { + if let Some(&v) = m.get(&i, &guard) { + assert_eq!(v, i + 7); + } + } + }); + } + }); +} + +fn get_flurry_u64_u64_guard_once(c: &mut Criterion) { + let mut group = c.benchmark_group("get_flurry_u64_u64_guard_once"); + group.throughput(Throughput::Elements(ITER as u64)); + let max = num_cpus::get(); + + for threads in 1..=max { + let map = Arc::new(task_insert_flurry_u64_u64_guard_every_it()); + + group.bench_with_input( + BenchmarkId::from_parameter(threads), + &threads, + |b, &threads| { + let pool = rayon::ThreadPoolBuilder::new() + .num_threads(threads) + .build() + .unwrap(); + pool.install(|| { + b.iter(|| task_get_flurry_u64_u64_guard_once(threads, map.clone())) + }); + }, + ); + } + + group.finish(); +} + +criterion_group!( + benches, + insert_flurry_u64_u64_guard_every_it, + get_flurry_u64_u64_guard_every_it, + insert_flurry_u64_u64_guard_once, + get_flurry_u64_u64_guard_once, +); +criterion_main!(benches); diff --git a/benches/flurry_hashbrown.rs b/benches/flurry_hashbrown.rs new file mode 100644 index 00000000..49490456 --- /dev/null +++ b/benches/flurry_hashbrown.rs @@ -0,0 +1,200 @@ +/* Benchmarks from `hashbrown` (https://github.com/rust-lang/hashbrown), + * adapted to flurry for comparison: + * + * This benchmark suite contains some benchmarks along a set of dimensions: + * Int key distribution: low bit heavy, top bit heavy, and random. + * Task: basic functionality: insert, insert_erase, lookup, lookup_fail, iter + * + * For the associated license information, please refer to hashbrown.LICENSE. + */ + +use criterion::{black_box, criterion_group, criterion_main, BenchmarkId, Criterion, Throughput}; +use flurry::{epoch, HashMap}; + +const SIZE: usize = 1000; + +#[derive(Clone, Copy)] +struct RandomKeys { + state: usize, +} + +impl RandomKeys { + fn new() -> Self { + RandomKeys { state: 0 } + } +} + +impl Iterator for RandomKeys { + type Item = usize; + fn next(&mut self) -> Option { + // Add 1 then multiply by some 32 bit prime. + self.state = self.state.wrapping_add(1).wrapping_mul(3_787_392_781); + Some(self.state) + } +} + +macro_rules! bench_suite { + ($bench_macro:ident, $bench_fn_name:ident, $group_name:expr $(,)?) => { + fn $bench_fn_name(c: &mut Criterion) { + let mut group = c.benchmark_group($group_name); + group.throughput(Throughput::Elements(SIZE as u64)); + + $bench_macro!(group, 0.., "low_guard_once"); + $bench_macro!(group, (0..).map(usize::swap_bytes), "high_guard_once"); + $bench_macro!(group, RandomKeys::new(), "random_guard_once"); + + group.finish(); + } + }; +} + +macro_rules! bench_insert { + ($group:ident, $keydist:expr, $bench_id: expr) => { + $group.bench_function(BenchmarkId::from_parameter($bench_id), |b| { + b.iter(|| { + let mut map = HashMap::with_capacity(SIZE as usize); + + let guard = epoch::pin(); + ($keydist).take(SIZE).for_each(|i| { + map.insert(i, i, &guard); + }); + black_box(&mut map); + }); + }); + }; +} + +bench_suite!( + bench_insert, + insert_flurry_hashbrown, + "insert_flurry_hashbrown", +); + +macro_rules! bench_insert_erase { + ($group:ident, $keydist:expr, $bench_id: expr) => { + let base = HashMap::with_capacity(SIZE as usize); + { + // NOTE: in testing, I tried running this without the local scope. + // not dropping the guard and pinning the epoch for the entire benchmark literally + // crashed multiple programs on my PC, so I advise not to do that... + let guard = epoch::pin(); + ($keydist).take(SIZE).for_each(|i| { + base.insert(i, i, &guard); + }); + } + let skip = ($keydist).take(SIZE); + + $group.bench_function(BenchmarkId::from_parameter($bench_id), |b| { + b.iter(|| { + let mut map = base.clone(); + let mut add_iter = skip.clone(); + let mut remove_iter = $keydist; + + // While keeping the size constant, + // replace the first keydist with the second. + let guard = epoch::pin(); + (&mut add_iter) + .zip(&mut remove_iter) + .take(SIZE) + .for_each(|(add, remove)| { + map.insert(add, add, &guard); + black_box(map.remove(&remove, &guard)); + }); + black_box(&mut map); + }); + }); + }; +} + +bench_suite!( + bench_insert_erase, + insert_erase_flurry_hashbrown, + "insert_erase_flurry_hashbrown", +); + +macro_rules! bench_lookup { + ($group:ident, $keydist:expr, $bench_id: expr) => { + let map = HashMap::with_capacity(SIZE as usize); + { + // see bench_insert_erase for a comment on the local scope + let guard = epoch::pin(); + ($keydist).take(SIZE).for_each(|i| { + map.insert(i, i, &guard); + }); + } + + $group.bench_function(BenchmarkId::from_parameter($bench_id), |b| { + b.iter(|| { + let guard = epoch::pin(); + ($keydist).take(SIZE).for_each(|i| { + black_box(map.get(&i, &guard)); + }); + }); + }); + }; +} + +bench_suite!(bench_lookup, get_flurry_hashbrown, "get_flurry_hashbrown",); + +macro_rules! bench_lookup_fail { + ($group:ident, $keydist:expr, $bench_id: expr) => { + let map = HashMap::with_capacity(SIZE as usize); + let mut iter = $keydist; + { + // see bench_insert_erase for a comment on the local scope + let guard = epoch::pin(); + (&mut iter).take(SIZE).for_each(|i| { + map.insert(i, i, &guard); + }); + } + + $group.bench_function(BenchmarkId::from_parameter($bench_id), |b| { + b.iter(|| { + let guard = epoch::pin(); + (&mut iter).take(SIZE).for_each(|i| { + black_box(map.get(&i, &guard)); + }); + }); + }); + }; +} + +bench_suite!( + bench_lookup_fail, + get_absent_flurry_hashbrown, + "get_absent_flurry_hashbrown", +); + +macro_rules! bench_iter { + ($group:ident, $keydist:expr, $bench_id: expr) => { + let map = HashMap::with_capacity(SIZE as usize); + { + // see bench_insert_erase for a comment on the local scope + let guard = epoch::pin(); + ($keydist).take(SIZE).for_each(|i| { + map.insert(i, i, &guard); + }); + } + + $group.bench_function(BenchmarkId::from_parameter($bench_id), |b| { + b.iter(|| { + let guard = epoch::pin(); + for k in map.iter(&guard) { + black_box(k); + } + }); + }); + }; +} + +bench_suite!(bench_iter, iter_flurry_hashbrown, "iter_flurry_hashbrown",); + +criterion_group!( + benches, + insert_flurry_hashbrown, + insert_erase_flurry_hashbrown, + get_flurry_hashbrown, + get_absent_flurry_hashbrown, + iter_flurry_hashbrown, +); +criterion_main!(benches); diff --git a/benches/hashbrown.LICENSE b/benches/hashbrown.LICENSE new file mode 100644 index 00000000..940c9442 --- /dev/null +++ b/benches/hashbrown.LICENSE @@ -0,0 +1,236 @@ +Hashbrown is licensed under either the Apache License, +Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0), +or the MIT license (http://opensource.org/licenses/MIT), +at your option. + +--------------------- MIT --------------------- + +Copyright (c) 2016 Amanieu d'Antras + +Permission is hereby granted, free of charge, to any +person obtaining a copy of this software and associated +documentation files (the "Software"), to deal in the +Software without restriction, including without +limitation the rights to use, copy, modify, merge, +publish, distribute, sublicense, and/or sell copies of +the Software, and to permit persons to whom the Software +is furnished to do so, subject to the following +conditions: + +The above copyright notice and this permission notice +shall be included in all copies or substantial portions +of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF +ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A +PARTICULAR PURPOSE AND NONINFRINGEMENT. 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