29 lines
831 B
Rust
29 lines
831 B
Rust
|
use std::mem::size_of;
|
||
|
|
||
|
use once_cell::sync::OnceCell;
|
||
|
|
||
|
const N_THREADS: usize = 32;
|
||
|
const N_ROUNDS: usize = 100_000_000;
|
||
|
|
||
|
static CELL: OnceCell<usize> = OnceCell::new();
|
||
|
|
||
|
fn main() {
|
||
|
let start = std::time::Instant::now();
|
||
|
let threads =
|
||
|
(0..N_THREADS).map(|i| std::thread::spawn(move || thread_main(i))).collect::<Vec<_>>();
|
||
|
for thread in threads {
|
||
|
thread.join().unwrap();
|
||
|
}
|
||
|
println!("{:?}", start.elapsed());
|
||
|
println!("size_of::<OnceCell<()>>() = {:?}", size_of::<OnceCell<()>>());
|
||
|
println!("size_of::<OnceCell<bool>>() = {:?}", size_of::<OnceCell<bool>>());
|
||
|
println!("size_of::<OnceCell<u32>>() = {:?}", size_of::<OnceCell<u32>>());
|
||
|
}
|
||
|
|
||
|
fn thread_main(i: usize) {
|
||
|
for _ in 0..N_ROUNDS {
|
||
|
let &value = CELL.get_or_init(|| i);
|
||
|
assert!(value < N_THREADS)
|
||
|
}
|
||
|
}
|