Function test_fair

datafusion/execution/src/memory_pool/pool.rs:631–695

()

    #[test]
    fn test_fair() {
        let pool = Arc::new(FairSpillPool::new(100)) as _;

        let r1 = MemoryConsumer::new("unspillable").register(&pool);
        // Can grow beyond capacity of pool
        r1.grow(2000);
        assert_eq!(pool.reserved(), 2000);

        let r2 = MemoryConsumer::new("r2")
            .with_can_spill(true)
            .register(&pool);
        // Can grow beyond capacity of pool
        r2.grow(2000);

        assert_eq!(pool.reserved(), 4000);

        let err = r2.try_grow(1).unwrap_err().strip_backtrace();
        assert_snapshot!(err, @"Resources exhausted: Failed to allocate additional 1.0 B for r2 with 2000.0 B already allocated for this reservation - 0.0 B remain available for the total memory pool: fair(pool_size: 100.0 B)");

        let err = r2.try_grow(1).unwrap_err().strip_backtrace();
        assert_snapshot!(err, @"Resources exhausted: Failed to allocate additional 1.0 B for r2 with 2000.0 B already allocated for this reservation - 0.0 B remain available for the total memory pool: fair(pool_size: 100.0 B)");

        r1.shrink(1990);
        r2.shrink(2000);

        assert_eq!(pool.reserved(), 10);

        r1.try_grow(10).unwrap();
        assert_eq!(pool.reserved(), 20);

        // Can grow r2 to 80 as only spilling consumer
        r2.try_grow(80).unwrap();
        assert_eq!(pool.reserved(), 100);

        r2.shrink(70);

        assert_eq!(r1.size(), 20);
        assert_eq!(r2.size(), 10);
        assert_eq!(pool.reserved(), 30);

        let r3 = MemoryConsumer::new("r3")
            .with_can_spill(true)
            .register(&pool);

        let err = r3.try_grow(70).unwrap_err().strip_backtrace();
        assert_snapshot!(err, @"Resources exhausted: Failed to allocate additional 70.0 B for r3 with 0.0 B already allocated for this reservation - 40.0 B remain available for the total memory pool: fair(pool_size: 100.0 B)");

        //Shrinking r2 to zero doesn't allow a3 to allocate more than 45
        r2.free();
        let err = r3.try_grow(70).unwrap_err().strip_backtrace();
        assert_snapshot!(err, @"Resources exhausted: Failed to allocate additional 70.0 B for r3 with 0.0 B already allocated for this reservation - 40.0 B remain available for the total memory pool: fair(pool_size: 100.0 B)");

        // But dropping r2 does
        drop(r2);
        assert_eq!(pool.reserved(), 20);
        r3.try_grow(80).unwrap();

        assert_eq!(pool.reserved(), 100);