Describe the algorithms

README.md

@@ -59,3 +59,18 @@ algorithms in Rust and benchmark them. Let the battle begin.
 
 [rust]: https://www.rust-lang.org/
 [gnuplot]: http://www.gnuplot.info/
+
+
+## Algorithms
+
+- `single thread`: No multi-threading or any optimization of any kind. Used as
+  a reference.
+- `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]: https://en.wikipedia.org/wiki/Longest-processing-time-first_scheduling

benches/job_scheduling.rs

@@ -1,13 +1,14 @@
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion};
 use rust_job_scheduling::algorithm::*;
-use rust_job_scheduling::data::SMALL;
+use rust_job_scheduling::data::*;
 use rust_job_scheduling::Task;
 
-const TEST_DATA: &[(&str, &[Task])] = &[("small", SMALL)];
+const TEST_DATA: &[(&str, &[Task])] = &[("10 tasks", T_10), ("500 tasks", T_500)];
 const TEST_FUNCS: &[(&str, &dyn Fn(&[Task]))] = &[
 	("single thread", &single_thread),
 	("rayon", &rayon),
 	("rayon sorted", &rayon_sorted),
+	("rayon sorted reverse", &rayon_sorted_reverse),
 ];
 
 fn job_scheduling_benchmark(c: &mut Criterion) {

src/algorithm/rayon.rs

@@ -7,6 +7,14 @@ pub fn rayon(data: &[Task]) {
 
 pub fn rayon_sorted(data: &[Task]) {
 	let mut data = data.to_vec();
+	// Shortest tasks first
 	data.sort();
-	rayon(&data)
+	rayon(&data);
+}
+
+pub fn rayon_sorted_reverse(data: &[Task]) {
+	let mut data = data.to_vec();
+	// Longest tasks first
+	data.sort_by(|a, b| a.cmp(b).reverse());
+	rayon(&data);
 }

src/data.rs

@@ -1,3 +1,5 @@
-mod small;
+mod t10;
+mod t500;
 
-pub use small::SMALL;
+pub use t10::T_10;
+pub use t500::T_500;

src/data/t10.rs

@@ -1,10 +1,6 @@
 use crate::Task;
 
-pub const SMALL: &[Task] = &[
-	Task {
-		data: b"eb17a235c386039c41c65bf5",
-		cost: 500,
-	},
+pub const T_10: &[Task] = &[
 	Task {
 		data: b"df33fd171cd4d311775ebe76",
 		cost: 100,