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#![cfg(all(test, feature = "future"))]
use std::sync::Arc;
use actix_rt::System;
use moka::future::Cache;
use tokio::sync::Barrier;
#[actix_rt::test]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
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.
// NOTE: Actix Runtime is single threaded.
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;
actix_rt::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;
std::thread::spawn(move || {
// It seems there is no way to get a SystemRunner from the current
// System (`System::current()`). So, create a new System.
let runner = System::new(); // Returns a SystemRunner.
// Wait for the all async tasks and threads to be spawned.
runner.block_on(my_barrier.wait());
// Insert 64 entries. (NUM_KEYS_PER_TASK = 64)
for key in start..end {
runner.block_on(my_cache.insert(key, value(key)));
assert_eq!(runner.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) {
runner.block_on(my_cache.invalidate(&key));
}
})
})
.collect();
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)));
}
}
System::current().stop();
Ok(())
}