1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
#![cfg(all(test, feature = "future"))]
use std::sync::Arc;
use moka::future::Cache;
use tokio::sync::Barrier;
#[tokio::test]
async fn main() {
const NUM_TASKS: usize = 12;
const NUM_THREADS: usize = 4;
const NUM_KEYS_PER_TASK: usize = 64;
fn value(n: usize) -> String {
format!("value {n}")
}
// Create a cache that can store up to 10,000 entries.
let cache = Cache::new(10_000);
let barrier = Arc::new(Barrier::new(NUM_THREADS + NUM_TASKS));
// Spawn async tasks and write to and read from the cache.
let tasks: Vec<_> = (0..NUM_TASKS)
.map(|i| {
// To share the same cache across the async tasks and OS threads, clone
// it. This is a cheap operation.
let my_cache = cache.clone();
let my_barrier = Arc::clone(&barrier);
let start = i * NUM_KEYS_PER_TASK;
let end = (i + 1) * NUM_KEYS_PER_TASK;
tokio::spawn(async move {
// Wait for the all async tasks and threads to be spawned.
my_barrier.wait().await;
// Insert 64 entries. (NUM_KEYS_PER_TASK = 64)
for key in start..end {
my_cache.insert(key, value(key)).await;
assert_eq!(my_cache.get(&key).await, Some(value(key)));
}
// Invalidate every 4 element of the inserted entries.
for key in (start..end).step_by(4) {
my_cache.invalidate(&key).await;
}
})
})
.collect();
// Spawn OS threads and write to and read from the cache.
let threads: Vec<_> = (0..NUM_THREADS)
.map(|i| i + NUM_TASKS)
.map(|i| {
let my_cache = cache.clone();
let my_barrier = Arc::clone(&barrier);
let start = i * NUM_KEYS_PER_TASK;
let end = (i + 1) * NUM_KEYS_PER_TASK;
let rt = tokio::runtime::Handle::current();
std::thread::spawn(move || {
// Wait for the all async tasks and threads to be spawned.
rt.block_on(my_barrier.wait());
// Insert 64 entries. (NUM_KEYS_PER_TASK = 64)
for key in start..end {
rt.block_on(my_cache.insert(key, value(key)));
assert_eq!(rt.block_on(my_cache.get(&key)), Some(value(key)));
}
// Invalidate every 4 element of the inserted entries.
for key in (start..end).step_by(4) {
rt.block_on(my_cache.invalidate(&key));
}
})
})
.collect();
// Wait for all tasks and threads to complete.
futures_util::future::join_all(tasks).await;
for t in threads {
t.join().unwrap();
}
// Verify the result.
for key in 0..(NUM_TASKS * NUM_KEYS_PER_TASK) {
if key % 4 == 0 {
assert_eq!(cache.get(&key).await, None);
} else {
assert_eq!(cache.get(&key).await, Some(value(key)));
}
}
}