feat(bench): add SQLite pool benchmarks for #158

Cargo.toml

@@ -366,6 +366,12 @@ path = "benches/sqlite/describe.rs"
 harness = false
 required-features = ["sqlite"]
 
+[[bench]]
+name = "sqlite-simple"
+path = "benches/sqlite/simple.rs"
+harness = false
+required-features = ["sqlite"]
+
 #
 # MySQL
 #

benches/sqlite/simple.rs

@@ -0,0 +1,147 @@
+use criterion::{criterion_group, criterion_main, Criterion};
+use futures_util::TryStreamExt;
+use sqlx::sqlite::{SqlitePool, SqlitePoolOptions};
+use sqlx::Executor;
+use sqlx::Row;
+
+// --- Helpers ---
+
+async fn setup_pool() -> SqlitePool {
+    let pool = SqlitePoolOptions::new()
+        .max_connections(5)
+        .min_connections(1)
+        .connect("sqlite::memory:")
+        .await
+        .unwrap();
+
+    pool.execute(
+        r#"
+        CREATE TABLE IF NOT EXISTS bench (
+            id INTEGER PRIMARY KEY,
+            i32_val INTEGER NOT NULL,
+            i64_val BIGINT NOT NULL,
+            f64_val REAL NOT NULL,
+            text_val TEXT NOT NULL,
+            blob_val BLOB NOT NULL
+        );
+        "#,
+    )
+    .await
+    .unwrap();
+
+    // Seed 10,000 rows for large result benchmarks.
+    // Using a recursive CTE to avoid 10K round-trips.
+    pool.execute(
+        r#"
+        WITH RECURSIVE cnt(id) AS (
+            SELECT 1
+            UNION ALL
+            SELECT id + 1 FROM cnt WHERE id < 10000
+        )
+        INSERT INTO bench (id, i32_val, i64_val, f64_val, text_val, blob_val)
+        SELECT
+            id,
+            id AS i32_val,
+            id * 1000 AS i64_val,
+            id * 1.5 AS f64_val,
+            'row_' || id AS text_val,
+            randomblob(64) AS blob_val
+        FROM cnt;
+        "#,
+    )
+    .await
+    .unwrap();
+
+    pool
+}
+
+// --- Benchmarks ---
+
+/// #1: Establish a new connection.
+async fn bench_connect() {
+    let mut conn = sqlx::sqlite::SqliteConnection::connect("sqlite::memory:")
+        .await
+        .unwrap();
+    let _ = sqlx::query_scalar::<_, i64>("SELECT 1")
+        .fetch_one(&mut conn)
+        .await
+        .unwrap();
+}
+
+/// #2: Checkout an idle connection from the pool.
+async fn bench_pool_checkout(pool: &SqlitePool) {
+    let mut conn = pool.acquire().await.unwrap();
+    let _ = sqlx::query_scalar::<_, i64>("SELECT 1")
+        .fetch_one(&mut *conn)
+        .await
+        .unwrap();
+}
+
+/// #3: Ping a connection.
+async fn bench_ping(pool: &SqlitePool) {
+    let mut conn = pool.acquire().await.unwrap();
+    conn.ping().await.unwrap();
+}
+
+/// #4: Small query, small results (TechEmpower single-row query).
+/// Single SELECT returning a handful of columns, one row.
+async fn bench_query_small(pool: &SqlitePool) {
+    let _row: (i64, i32, String) = sqlx::query_as("SELECT 1, 2, 'hello'")
+        .fetch_one(pool)
+        .await
+        .unwrap();
+}
+
+/// #5: Small query, huge results (10K rows, 5+ columns with String and BLOB).
+async fn bench_query_large(pool: &SqlitePool) {
+    let mut rows = sqlx::query(
+        "SELECT id, i32_val, i64_val, f64_val, text_val, blob_val FROM bench",
+    )
+    .fetch(pool);
+
+    let mut count = 0u64;
+    while let Some(row) = rows.try_next().await.unwrap() {
+        let _id: i64 = row.get("id");
+        let _i32: i32 = row.get("i32_val");
+        let _i64: i64 = row.get("i64_val");
+        let _f64: f64 = row.get("f64_val");
+        let _text: &str = row.get("text_val");
+        let _blob: &[u8] = row.get("blob_val");
+        count += 1;
+    }
+    assert_eq!(count, 10_000);
+}
+
+// --- Criterion harness ---
+
+fn criterion_benchmarks(c: &mut Criterion) {
+    let runtime = tokio::runtime::Runtime::new().unwrap();
+    let pool = runtime.block_on(setup_pool());
+
+    let mut group = c.benchmark_group("sqlx_sqlite");
+
+    group.bench_function("connect", |b| {
+        b.to_async(&runtime).iter(|| bench_connect());
+    });
+
+    group.bench_function("pool_checkout", |b| {
+        b.to_async(&runtime).iter(|| bench_pool_checkout(&pool));
+    });
+
+    group.bench_function("ping", |b| {
+        b.to_async(&runtime).iter(|| bench_ping(&pool));
+    });
+
+    group.bench_function("query_small", |b| {
+        b.to_async(&runtime).iter(|| bench_query_small(&pool));
+    });
+
+    group.bench_function("query_large_10k", |b| {
+        b.to_async(&runtime).iter(|| bench_query_large(&pool));
+    });
+
+    group.finish();
+}
+
+criterion_group!(benches, criterion_benchmarks);
+criterion_main!(benches);