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//! ACL owner-cache benchmark.
//!
//! Models the owner short-circuit in `PgAclEngine::check` (the common case: a
//! user touching their own files). Before the cache, every authorization check
//! on a folder/file ran one PK query `SELECT user_id FROM storage.folders WHERE
//! id=$1` — a DB round-trip that also occupies a pool connection. After, repeat
//! checks for the same resource hit an in-memory moka cache (owner is immutable).
//!
//! This isolates that exact query vs a moka hit, under concurrency C, against the
//! real dev Postgres. It shows both the latency win and — by NOT touching the
//! pool — the relief it gives the connection pool (ties into the pool benchmark).
//!
//! Run (needs the dev Postgres up with at least one folder; reads DATABASE_URL):
//! cargo run --release --features bench --example bench_owner_cache
//! Tunables: BENCH_CONCURRENCY (64), BENCH_POOL_SIZE (20 = prod default),
//! BENCH_SECONDS (4).
use std::env;
use std::time::{Duration, Instant};
use moka::future::Cache;
use sqlx::Row;
use sqlx::postgres::PgPoolOptions;
use uuid::Uuid;
fn env_or<T: std::str::FromStr>(key: &str, default: T) -> T {
env::var(key)
.ok()
.and_then(|v| v.parse().ok())
.unwrap_or(default)
}
struct Stats {
reqs: u64,
tput: f64,
p50_us: f64,
p95_us: f64,
p99_us: f64,
max_us: f64,
}
fn summarize(mut lats_ns: Vec<u64>, elapsed: f64) -> Stats {
lats_ns.sort_unstable();
let n = lats_ns.len();
let pct = |q: f64| -> f64 {
if n == 0 {
return 0.0;
}
let idx = ((q / 100.0) * (n as f64 - 1.0)).round() as usize;
lats_ns[idx.min(n - 1)] as f64 / 1000.0
};
Stats {
reqs: n as u64,
tput: n as f64 / elapsed,
p50_us: pct(50.0),
p95_us: pct(95.0),
p99_us: pct(99.0),
max_us: pct(100.0),
}
}
#[tokio::main(flavor = "multi_thread")]
async fn main() {
dotenvy::dotenv().ok();
let url = env::var("DATABASE_URL")
.or_else(|_| env::var("OXICLOUD_DB_CONNECTION_STRING"))
.expect("set DATABASE_URL — the dev Postgres URL");
let concurrency: usize = env_or("BENCH_CONCURRENCY", 64);
let pool_size: u32 = env_or("BENCH_POOL_SIZE", 20); // production default
let secs: u64 = env_or("BENCH_SECONDS", 4);
let pool = PgPoolOptions::new()
.max_connections(pool_size)
.min_connections(pool_size)
.acquire_timeout(Duration::from_secs(10))
.connect(&url)
.await
.expect("connect dev Postgres");
// A real folder + its owner to check against.
let Some(row) = sqlx::query("SELECT id, user_id FROM storage.folders LIMIT 1")
.fetch_optional(&pool)
.await
.expect("query folder")
else {
eprintln!("No folders in the dev DB — seed some first (`just load-seed`).");
return;
};
let folder_id: Uuid = row.get("id");
let owner_id: Uuid = row.get("user_id");
println!("\n###########################################################");
println!("# ACL owner-cache benchmark (owner short-circuit path)");
println!("# concurrency: {concurrency} pool: {pool_size} window: {secs}s/mode");
println!("# folder {folder_id} owner {owner_id}");
println!("###########################################################\n");
// ── BEFORE: one PK owner query per check (hits DB + pool) ──────────────
let uncached = {
let start = Instant::now();
let deadline = start + Duration::from_secs(secs);
let mut handles = Vec::with_capacity(concurrency);
for _ in 0..concurrency {
let pool = pool.clone();
handles.push(tokio::spawn(async move {
let mut lats = Vec::with_capacity(16384);
while Instant::now() < deadline {
let t = Instant::now();
let _: Uuid =
sqlx::query_scalar("SELECT user_id FROM storage.folders WHERE id = $1")
.bind(folder_id)
.fetch_one(&pool)
.await
.expect("owner query");
lats.push(t.elapsed().as_nanos() as u64);
}
lats
}));
}
let mut all = Vec::new();
for h in handles {
all.extend(h.await.expect("join"));
}
let s = summarize(all, start.elapsed().as_secs_f64());
(s.reqs, s) // reqs == DB queries
};
// ── AFTER: moka hit per check (no DB, no pool) ────────────────────────
let cache: Cache<Uuid, Uuid> = Cache::builder()
.max_capacity(100_000)
.time_to_live(Duration::from_secs(300))
.build();
cache.insert(folder_id, owner_id).await; // 1 warm-up "query"
let cached = {
let start = Instant::now();
let deadline = start + Duration::from_secs(secs);
let mut handles = Vec::with_capacity(concurrency);
for _ in 0..concurrency {
let cache = cache.clone();
handles.push(tokio::spawn(async move {
let mut lats = Vec::with_capacity(65536);
while Instant::now() < deadline {
let t = Instant::now();
let owner = cache.get(&folder_id).await.expect("cache hit");
std::hint::black_box(owner);
lats.push(t.elapsed().as_nanos() as u64);
}
lats
}));
}
let mut all = Vec::new();
for h in handles {
all.extend(h.await.expect("join"));
}
summarize(all, start.elapsed().as_secs_f64())
};
pool.close().await;
let (uncached_queries, a) = uncached;
println!(
"| {:<16} | {:>10} | {:>11} | {:>9} | {:>9} | {:>9} | {:>10} |",
"mode", "DB queries", "checks/s", "p50 µs", "p95 µs", "p99 µs", "max µs"
);
println!(
"|{:-<18}|{:-<12}|{:-<13}|{:-<11}|{:-<11}|{:-<11}|{:-<12}|",
"", "", "", "", "", "", ""
);
println!(
"| {:<16} | {:>10} | {:>11.0} | {:>9.1} | {:>9.1} | {:>9.1} | {:>10.1} |",
"uncached (before)", uncached_queries, a.tput, a.p50_us, a.p95_us, a.p99_us, a.max_us
);
println!(
"| {:<16} | {:>10} | {:>11.0} | {:>9.3} | {:>9.3} | {:>9.3} | {:>10.3} |",
"cached (after)",
1,
cached.tput,
cached.p50_us,
cached.p95_us,
cached.p99_us,
cached.max_us
);
println!(
"\nPer authorized action on an owned resource, the cache removes 1 DB query\n\
+ 1 pool-connection occupancy, turning a {:.0} µs round-trip into a {:.3} µs\n\
memory hit ({:.0}× lower p99). Over a network/loaded DB the absolute saving is\n\
larger; the freed connections directly relieve the pool (see DB-POOL.md).\n",
a.p99_us,
cached.p99_us,
if cached.p99_us > 0.0 {
a.p99_us / cached.p99_us
} else {
0.0
}
);
}