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4 changed files with 1 additions and 51 deletions

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@ -65,17 +65,13 @@ algorithms in Rust and benchmark them. Let the battle begin.
- `single thread`: No multi-threading or any optimization of any kind. Used as
a reference.
- `multi threads`: Manual multi-threading but no optimization of any kind. Used
as a reference.
- `lpt`: Manual multi-threading. Tasks are sorted so the shortest ones are
executed first. This is the [longest-processing-time-first algorithm][lpt].
- `rayon`: Multi-threading provided by the `rayon` crate, but no optimization
of any kind. Used as a reference.
- `rayon sorted`: Multi-threading provided by the `rayon` crate. Tasks are
sorted so the shortest ones are executed first.
- `rayon sorted reverse`: Multi-threading provided by the `rayon` crate. Tasks
are sorted so the longest ones are executed first. This should behave as an
LPT.
[LPT][lpt].
- `rayon sorted reverse`: Similar to `rayon sorted reverse`, but tasks are
sorted from shortest to longest and are then iterated in the reverse order.

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@ -6,8 +6,6 @@ use rust_job_scheduling::Task;
const TEST_DATA: &[(&str, &[Task])] = &[("10 tasks", T_10), ("500 tasks", T_500)];
const TEST_FUNCS: &[(&str, &dyn Fn(&[Task]))] = &[
("single thread", &single_thread),
("multi threads", &multi_threads),
("lpt", &lpt),
("rayon", &rayon),
("rayon sorted", &rayon_sorted),
("rayon sorted reverse", &rayon_sorted_reverse),

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@ -1,7 +1,5 @@
mod lpt;
mod rayon;
mod single_thread;
pub use lpt::*;
pub use rayon::*;
pub use single_thread::single_thread;

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@ -1,42 +0,0 @@
use crate::Task;
use std::sync::{Arc, Mutex};
use std::thread;
pub fn lpt(data: &[Task]) {
let mut data = data.to_vec();
data.sort();
run_multi(data);
}
pub fn multi_threads(data: &[Task]) {
let data = data.to_vec();
run_multi(data);
}
#[inline(always)]
fn run_multi(data: Vec<Task>) {
let data_mt = Arc::new(Mutex::new(data));
let nb_threads = thread::available_parallelism()
.map(|n| n.get())
.unwrap_or(1);
let mut handles = Vec::with_capacity(nb_threads);
for _ in 0..nb_threads {
let dt = data_mt.clone();
let h = thread::spawn(move || loop {
let mut data = dt.lock().unwrap();
let task = match data.pop() {
Some(t) => t,
None => {
break;
}
};
std::mem::drop(data);
task.execute();
});
handles.push(h);
}
for h in handles {
let _ = h.join();
}
}